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Cummings JF, Polhemus ME, Kester KE, Ockenhouse CF, Gasser RA, Coyne P, Wortmann G, Nielsen RK, Schaecher K, Holland CA, Krzych U, Tornieporth N, Soisson LA, Angov E, Heppner DG. A phase IIa, randomized, double-blind, safety, immunogenicity and efficacy trial of Plasmodium falciparum vaccine antigens merozoite surface protein 1 and RTS,S formulated with AS02 adjuvant in healthy, malaria-naïve adults. Vaccine 2024; 42:3066-3074. [PMID: 38584058 DOI: 10.1016/j.vaccine.2024.03.072] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/13/2023] [Revised: 03/15/2024] [Accepted: 03/25/2024] [Indexed: 04/09/2024]
Abstract
BACKGROUND To improve the efficacy of Plasmodium falciparum malaria vaccine RTS,S/AS02, we conducted a study in 2001 in healthy, malaria-naïve adults administered RTS,S/AS02 in combination with FMP1, a recombinant merozoite surface-protein-1, C-terminal 42kD fragment. METHODS A double-blind Phase I/IIa study randomized N = 60 subjects 1:1:1:1 to one of four groups, N = 15/group, to evaluate safety, immunogenicity, and efficacy of intra-deltoid half-doses of RTS,S/AS02 and FMP1/AS02 administered in the contralateral (RTS,S + FMP1-separate) or same (RTS,S + FMP1-same) sites, or FMP1/AS02 alone (FMP1-alone), or RTS,S/AS02 alone (RTS,S-alone) on a 0-, 1-, 3-month schedule. Subjects receiving three doses of vaccine and non-immunized controls (N = 11) were infected with homologous P. falciparum 3D7 sporozoites by Controlled Human Malaria Infection (CHMI). RESULTS Subjects in all vaccination groups experienced mostly mild or moderate local and general adverse events that resolved within eight days. Anti-circumsporozoite antibody levels were lower when FMP1 and RTS,S were co-administered at the same site (35.0 µg/mL: 95 % CI 20.3-63), versus separate arms (57.4 µg/mL: 95 % CI 32.3-102) or RTS,S alone (62.0 µg/mL: 95 % CI: 37.8-101.8). RTS,S-specific lymphoproliferative responses and ex vivo ELISpot CSP-specific interferon-gamma (IFN-γ) responses were indistinguishable among groups receiving RTS,S/AS02. There was no difference in antibody to FMP1 among groups receiving FMP1/AS02. After CHMI, groups immunized with a RTS,S-containing regimen had ∼ 30 % sterile protection against parasitemia, and equivalent delays in time-to-parasitemia. The FMP1/AS02 alone group showed no sterile immunity or delay in parasitemia. CONCLUSION Co-administration of RTS,S and FMP1/AS02 reduced anti-RTS,S antibody, but did not affect tolerability, cellular immunity, or efficacy in a stringent CHMI model. Absence of efficacy or delay of patency in the sporozoite challenge model in the FMP1/AS02 group did not rule out efficacy of FMP1/AS02 in an endemic population. However, a Phase IIb trial of FMP1/AS02 in children in malaria-endemic Kenya did not demonstrate efficacy against natural infection. CLINICALTRIALS gov identifier: NCT01556945.
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Affiliation(s)
- J F Cummings
- Walter Reed Army Institute of Research, Silver Spring, MD, USA
| | - M E Polhemus
- Walter Reed Army Institute of Research, Silver Spring, MD, USA
| | - K E Kester
- Walter Reed Army Institute of Research, Silver Spring, MD, USA
| | - C F Ockenhouse
- Walter Reed Army Institute of Research, Silver Spring, MD, USA
| | - R A Gasser
- Walter Reed Army Institute of Research, Silver Spring, MD, USA
| | - P Coyne
- Walter Reed Army Institute of Research, Silver Spring, MD, USA
| | - G Wortmann
- Walter Reed Army Institute of Research, Silver Spring, MD, USA
| | - R K Nielsen
- Walter Reed Army Institute of Research, Silver Spring, MD, USA
| | - K Schaecher
- Walter Reed Army Institute of Research, Silver Spring, MD, USA
| | - C A Holland
- Walter Reed Army Institute of Research, Silver Spring, MD, USA
| | - U Krzych
- Walter Reed Army Institute of Research, Silver Spring, MD, USA
| | | | - L A Soisson
- Malaria Vaccine Development Program, United States Agency for International Development, Washington, DC, USA
| | - E Angov
- Walter Reed Army Institute of Research, Silver Spring, MD, USA.
| | - D G Heppner
- Walter Reed Army Institute of Research, Silver Spring, MD, USA
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Wang S, Wang CY, Kuo HK, Peng WJ, Huang JH, Kuo BS, Lin F, Liu YJ, Liu Z, Wu HT, Ding S, Hou KL, Cheng J, Yang YT, Jiang MH, Wang MS, Chen T, Xia WG, Lin E, Hung CH, Chen HJ, Shih Z, Lin YL, Ryan V, Hu MM, Heppner DG, Malherbe DC, Periasamy S, Kuzmina N, Subramani C, Hellerstein M, Monath TP, Rumyantsev A, Bukreyev A, Guirakhoo F. A Novel RBD-Protein/Peptide Vaccine Elicits Broadly Neutralizing Antibodies and Protects Mice and Macaques against SARS-CoV-2. Emerg Microbes Infect 2022; 11:2724-2734. [DOI: 10.1080/22221751.2022.2140608] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/03/2022]
Affiliation(s)
| | - Chang Yi Wang
- United Biomedical Inc., Asia, Taipei, Taiwan
- United BioPharma, HuKo, Hsin Chu, Taiwan
- United Biomedical Inc., Hauppauge, NY, USA
| | - Hui-Kai Kuo
- United Biomedical Inc., Asia, Taipei, Taiwan
| | | | | | | | - Feng Lin
- United Biomedical Inc., Hauppauge, NY, USA
| | | | - Zhi Liu
- United Biomedical Inc., Hauppauge, NY, USA
| | | | | | | | | | | | | | | | - Tony Chen
- United Biomedical Inc., Asia, Taipei, Taiwan
| | | | - Ed Lin
- United Biomedical Inc., Hauppauge, NY, USA
| | | | | | | | | | | | - Mei Mei Hu
- Vaxxinity, Inc., Dallas, TX, USA
- United BioPharma, HuKo, Hsin Chu, Taiwan
- United Biomedical Inc., Hauppauge, NY, USA
| | | | - Delphine C. Malherbe
- Department of Pathology, University of Texas Medical Branch, Galveston, TX, USA
- Galveston National Laboratory, Galveston, TX, USA
| | - Sivakumar Periasamy
- Department of Pathology, University of Texas Medical Branch, Galveston, TX, USA
- Galveston National Laboratory, Galveston, TX, USA
| | - Natalia Kuzmina
- Department of Pathology, University of Texas Medical Branch, Galveston, TX, USA
- Galveston National Laboratory, Galveston, TX, USA
| | - Chandru Subramani
- Department of Pathology, University of Texas Medical Branch, Galveston, TX, USA
- Galveston National Laboratory, Galveston, TX, USA
| | | | | | | | - Alexander Bukreyev
- Department of Pathology, University of Texas Medical Branch, Galveston, TX, USA
- Department of Microbiology & Immunology, University of Texas Medical Branch, Galveston, TX, USA
- Galveston National Laboratory, Galveston, TX, USA
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3
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Wang CY, Hwang KP, Kuo HK, Peng WJ, Shen YH, Kuo BS, Huang JH, Liu H, Ho YH, Lin F, Ding S, Liu Z, Wu HT, Huang CT, Lee YJ, Liu MC, Yang YC, Lu PL, Tsai HC, Lee CH, Shi ZY, Liu CE, Liao CH, Chang FY, Cheng HC, Wang FD, Hou KL, Cheng J, Wang MS, Yang YT, Chiu HC, Jiang MH, Shih HY, Shen HY, Chang PY, Lan YR, Chen CT, Lin YL, Liang JJ, Liao CC, Chou YC, Morris MK, Hanson CV, Guirakhoo F, Hellerstein M, Yu HJ, King CC, Kemp T, Heppner DG, Monath TP. A multitope SARS-COV-2 vaccine provides long-lasting B cell and T cell immunity against Delta and Omicron variants. J Clin Invest 2022; 132:157707. [PMID: 35316221 PMCID: PMC9106357 DOI: 10.1172/jci157707] [Citation(s) in RCA: 42] [Impact Index Per Article: 21.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/17/2021] [Accepted: 03/16/2022] [Indexed: 11/19/2022] Open
Abstract
Background The Delta and Omicron variants of SARS-CoV-2 are currently responsible for breakthrough infections due to waning immunity. We report phase I/II trial results of UB-612, a multitope subunit vaccine containing S1-RBD-sFc protein and rationally designed promiscuous peptides representing sarbecovirus conserved helper T cell and cytotoxic T lymphocyte epitopes on the nucleocapsid (N), membrane (M), and spike (S2) proteins. Method We conducted a phase I primary 2-dose (28 days apart) trial of 10, 30, or 100 μg UB-612 in 60 healthy young adults 20 to 55 years old, and 50 of them were boosted with 100 μg of UB-612 approximately 7 to 9 months after the second dose. A separate placebo-controlled and randomized phase II study was conducted with 2 doses of 100 μg of UB-612 (n = 3,875, 18–85 years old). We evaluated interim safety and immunogenicity of phase I until 14 days after the third (booster) dose and of phase II until 28 days after the second dose. Results No vaccine-related serious adverse events were recorded. The most common solicited adverse events were injection site pain and fatigue, mostly mild and transient. In both trials, UB-612 elicited respective neutralizing antibody titers similar to a panel of human convalescent sera. The most striking findings were long-lasting virus-neutralizing antibodies and broad T cell immunity against SARS-CoV-2 variants of concern (VoCs), including Delta and Omicron, and a strong booster-recalled memory immunity with high cross-reactive neutralizing titers against the Delta and Omicron VoCs. Conclusion UB-612 has presented a favorable safety profile, potent booster effect against VoCs, and long-lasting B and broad T cell immunity that warrants further development for both primary immunization and heterologous boosting of other COVID-19 vaccines. Trial Registration ClinicalTrials.gov: NCT04545749, NCT04773067, and NCT04967742. Funding UBI Asia, Vaxxinity Inc., and Taiwan Centers for Disease Control, Ministry of Health and Welfare.
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Affiliation(s)
| | - Kao-Pin Hwang
- Division of Infectious Diseases, China Medical University Children's Hospital, Taichung City, Taiwan
| | - Hui-Kai Kuo
- Designed Vaccine Translation Medical Center, UBI Asia, Hsinchu, Taiwan
| | - Wen-Jiun Peng
- Administrative Management Center, UBI Asia, Hsinchu, Taiwan
| | - Yea-Huei Shen
- Medical and Clinical Operation, StatPlus, Taipei, Taiwan
| | - Be-Sheng Kuo
- Preclinical and ImmunoPharmacology Center, UBI Asia, Hsinchu, Taiwan
| | | | | | - Yu-Hsin Ho
- Regulatory Affairs, UBI Asia, Hsinchu, Taiwan
| | - Feng Lin
- R&D Center, United Bioimedical, Inc., Hauppauge, United States of America
| | - Shuang Ding
- R&D Center, United Biomedical, Inc., Hauppauge, United States of America
| | - Zhi Liu
- R&D Center, United Biomedical, Inc., Hauppauge, United States of America
| | | | - Ching-Tai Huang
- Department of Infectious Disease, Chang Gung University, Chang Gung Memorial Hospital, Linkou, Taiwan
| | - Yuarn-Jang Lee
- Division of Infectious Diseases, Taipei Medical University Hospital, Taipei, Taiwan
| | - Ming-Che Liu
- R&D, Taipei Medical University Hospital, Taipei, Taiwan
| | - Yi-Ching Yang
- Ministry of Health and Welfare, National Cheng Kung University and Hospital, Tainan, Taiwan
| | - Po-Liang Lu
- Department of Internal Medicine, Kaohsiung Medical University Hospital, Kaohsiung, Taiwan
| | - Hung-Chin Tsai
- School of Medicine, Kaohsiung Veterans General Hospital, Kaoshiung, Taiwan
| | - Chen-Hsiang Lee
- Division of Infectious Diseases, Department of Internal Medicine, Chang Gung Memorial Hospital, Kaohsiung, Taiwan
| | - Zhi-Yuan Shi
- Department of Medical Affairs, Taichung Veterans General Hospital, Taichung, Taiwan
| | - Chun-Eng Liu
- Department of Medical Affairs, Changhua Christian Hospital, Changhua, Taiwan
| | - Chun-Hsing Liao
- Department of Medical Affairs, Far Eastern Memorial Hospital, New Taipei, Taiwan
| | - Feng-Yee Chang
- Department of Internal Medicine, Tri-Service General Hospital, Taipei, Taiwan
| | - Hsiang-Cheng Cheng
- Department of Medical Affairs, Tri-Service General Hospital, Taipei, Taiwan
| | - Fu-Der Wang
- Department of Internal Medicine, Taipei Veterans General Hospital, Taipei, Taiwan
| | - Kuo-Liang Hou
- Department of Preclinical Research, UBI Asia, Hsinchu, Taiwan
| | - Jennifer Cheng
- Department of Preclinical Research, UBI Asia, Hsinchu, Taiwan
| | - Min-Sheng Wang
- Department of Clinical Research, UBI Asia, Hsinchu, Taiwan
| | - Ya-Ting Yang
- Department of Preclinical Research, UBI Asia, Hsinchu, Taiwan
| | - Han-Chen Chiu
- Department of Medical Affairs, UBI Asia, Hsinchu, Taiwan
| | - Ming-Han Jiang
- Department of Preclinical Research, UBI Asia, Hsinchu, Taiwan
| | - Hao-Yu Shih
- Department of Preclinical Research, UBI Asia, Hsinchu, Taiwan
| | - Hsuan-Yu Shen
- Department of Clinical Research, UBI Asia, Hsinchu, Taiwan
| | - Po-Yen Chang
- Department of Clinical Research, UBI Asia, Hsinchu, Taiwan
| | - Yu-Rou Lan
- Department of Preclinical Research, UBI Asia, Hsinchu, Taiwan
| | - Chi-Tian Chen
- Biostatistics and Data Management, StatPlus, Taipei, Taiwan
| | - Yi-Ling Lin
- Institute of Biomedical Sciences, Academia Sinica, Taipei, Taiwan
| | - Jian-Jong Liang
- Biomedical Translation Research Center (bioTReC) Academia Sinica, Taipei, Taiwan
| | - Chun-Che Liao
- Department of Medical Affairs, Biomedical Translation Research Center (bioTReC) Academia Sinica, Taipei, Taiwan
| | - Yu-Chi Chou
- Department of Statistics, Biomedical Translation Research Center (bioTReC) Academia Sinica, Taipei, Taiwan
| | - Mary Kate Morris
- Viral and Rickettsial Disease Laboratory, California Department of Public Health, Richmond, United States of America
| | - Carl V Hanson
- Viral and Rickettsial Disease Laboratory, California Department of Public Health, Richmond, United States of America
| | - Farshad Guirakhoo
- Department of Clinical Research, Vaxxinity Inc., Dallas, United States of America
| | - Michael Hellerstein
- Department of Preclinical Research, Vaxxinity Inc., Dallas, United States of America
| | - Hui Jing Yu
- Department of Clinical Research, Vaxxinity Inc., Dallas, United States of America
| | - Chwan-Chuen King
- Department of Medical, Institute of Epidemiology and Preventive Medicine, College of Public Health, National Taiwan University, Taipei, Taiwan
| | - Tracy Kemp
- Department of Clinical Research, Vaxxinity, Inc., Dallas, United States of America
| | - D Gray Heppner
- Department of Clinical Research, Vaxxinity, Inc., Dallas, United States of America
| | - Thomas P Monath
- Department of Clinical Research, Vaxxinity, Inc., Dallas, United States of America
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Monath TP, Fast PE, Modjarrad K, Clarke DK, Martin BK, Fusco J, Nichols R, Heppner DG, Simon JK, Dubey S, Troth SP, Wolf J, Singh V, Coller BA, Robertson JS. rVSVΔG-ZEBOV-GP (also designated V920) recombinant vesicular stomatitis virus pseudotyped with Ebola Zaire Glycoprotein: Standardized template with key considerations for a risk/benefit assessment. Vaccine X 2019; 1:100009. [PMID: 31384731 PMCID: PMC6668225 DOI: 10.1016/j.jvacx.2019.100009] [Citation(s) in RCA: 58] [Impact Index Per Article: 11.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/30/2018] [Accepted: 12/07/2018] [Indexed: 12/14/2022] Open
Abstract
The Brighton Collaboration Viral Vector Vaccines Safety Working Group (V3SWG) was formed to evaluate the safety and characteristics of live, recombinant viral vector vaccines. A recent publication by the V3SWG described live, attenuated, recombinant vesicular stomatitis virus (rVSV) as a chimeric virus vaccine for HIV-1 (Clarke et al., 2016). The rVSV vector system is being explored as a platform for development of multiple vaccines. This paper reviews the molecular and biological features of the rVSV vector system, followed by a template with details on the safety and characteristics of a rVSV vaccine against Zaire ebolavirus (ZEBOV). The rVSV-ZEBOV vaccine is a live, replication competent vector in which the VSV glycoprotein (G) gene is replaced with the glycoprotein (GP) gene of ZEBOV. Multiple copies of GP are expressed and assembled into the viral envelope responsible for inducing protective immunity. The vaccine (designated V920) was originally constructed by the National Microbiology Laboratory, Public Health Agency of Canada, further developed by NewLink Genetics Corp. and Merck & Co., and is now in final stages of registration by Merck. The vaccine is attenuated by deletion of the principal virulence factor of VSV (the G protein), which also removes the primary target for anti-vector immunity. The V920 vaccine caused no toxicities after intramuscular (IM) or intracranial injection of nonhuman primates and no reproductive or developmental toxicity in a rat model. In multiple studies, cynomolgus macaques immunized IM with a wide range of virus doses rapidly developed ZEBOV-specific antibodies measured in IgG ELISA and neutralization assays and were fully protected against lethal challenge with ZEBOV virus. Over 20,000 people have received the vaccine in clinical trials; the vaccine has proven to be safe and well tolerated. During the first few days after vaccination, many vaccinees experience a mild acute-phase reaction with fever, headache, myalgia, and arthralgia of short duration; this period is associated with a low-level viremia, activation of anti-viral genes, and increased levels of chemokines and cytokines. Oligoarthritis and rash appearing in the second week occur at a low incidence, and are typically mild-moderate in severity and self-limited. V920 vaccine was used in a Phase III efficacy trial during the West African Ebola epidemic in 2015, showing 100% protection against Ebola Virus Disease, and it has subsequently been deployed for emergency control of Ebola outbreaks in central Africa. The template provided here provides a comprehensive picture of the first rVSV vector to reach the final stage of development and to provide a solution to control of an alarming human disease.
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Affiliation(s)
| | - Patricia E Fast
- International AIDS Vaccine Initiative, New York, NY 10004, United States
| | - Kayvon Modjarrad
- Walter Reed Army Institute of Research, Silver Spring, MD 20910, United States
| | | | | | - Joan Fusco
- NewLink Genetics Corp, Ames, IA, United States
| | | | | | - Jakub K Simon
- Merck & Co., Inc., Kenilworth, NJ 07033, United States
| | - Sheri Dubey
- Merck & Co., Inc., Kenilworth, NJ 07033, United States
| | - Sean P Troth
- Merck & Co., Inc., Kenilworth, NJ 07033, United States
| | - Jayanthi Wolf
- Merck & Co., Inc., Kenilworth, NJ 07033, United States
| | - Vidisha Singh
- Immunology and Molecular Pathogenesis, Emory University, Atlanta, GA 30322, United States
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5
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ElSherif MS, Brown C, MacKinnon-Cameron D, Li L, Racine T, Alimonti J, Rudge TL, Sabourin C, Silvera P, Hooper JW, Kwilas SA, Kilgore N, Badorrek C, Ramsey WJ, Heppner DG, Kemp T, Monath TP, Nowak T, McNeil SA, Langley JM, Halperin SA. Assessing the safety and immunogenicity of recombinant vesicular stomatitis virus Ebola vaccine in healthy adults: a randomized clinical trial. CMAJ 2017. [PMID: 28630358 DOI: 10.1503/cmaj.170074] [Citation(s) in RCA: 62] [Impact Index Per Article: 8.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/01/2022] Open
Abstract
BACKGROUND The 2013-2016 Ebola virus outbreak in West Africa was the most widespread in history. In response, alive attenuated recombinant vesicular stomatitis virus (rVSV) vaccine expressing Zaire Ebolavirus glycoprotein (rVSVΔG-ZEBOV-GP) was evaluated in humans. METHODS In a phase 1, randomized, dose-ranging, observer-blind, placebo-controlled trial, healthy adults aged 18-65 years were randomized into 4 groups of 10 to receive one of 3 vaccine doses or placebo. Follow-up visits spanned 180 days postvaccination for safety monitoring, immunogenicity testing and any rVSV virus shedding. RESULTS Forty participants were injected with rVSVΔG-ZEBOV-GP vaccine (n = 30) or saline placebo (n = 10). No serious adverse events related to the vaccine or participant withdrawals were reported. Solicited adverse events during the 14-day follow-up period were mild to moderate and self-limited, with the exception of injection-site pain and headache. Viremia following vaccination was transient and no longer detectable after study day 3, with no virus shedding in saliva or urine. All vaccinated participants developed serum immunoglobulin G (IgG), as measured by Ebola virus envelope glycoprotein-based enzyme-linked immunosorbent assay (ELISA). Immunogenicity was comparable across all dose groups, and sustained IgG titers were detectable through to the last visit, at study day 180. INTERPRETATION In this phase 1 study, there were no safety concerns after a single dose of rVSVΔG-ZEBOV-GP vaccine. IgG ELISA showed persistent high titers at 180 days postimmunization. There was a period of reactogenicity, but in general, the vaccine was well tolerated. This study provides evidence of the safety and immunogenicity of rVSVΔG-ZEBOV-GP vaccine and importance of its further investigation. Trial registration: Clinical-Trials.gov no., NCT02374385.
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Affiliation(s)
- May S ElSherif
- Canadian Center for Vaccinology (ElSherif, Brown, MacKinnon-Cameron, Li, McNeil, Langley, Halperin), IWK Health Centre and Nova Scotia Health Authority, Dalhousie University, Halifax, NS; National Microbiology Laboratory (Racine, Alimonti), Winnipeg, Man.; Battelle Biomedical Research Center (Rudge, Sabourin), Columbus, Ohio; United States Army Medical Research Institute of Infectious Disease (Silvera, Hooper, Kwilas), Fort Detrick, Md.; Joint Program Executive Office for Chemical and Biological Defense Medical Countermeasure Systems' Joint Vaccine Acquisition Program (Kilgore, Badorrek), Fort Detrick, Md.; BioProtection Systems/NewLink Genetics Corporation (Ramsey, Heppner, Kemp, Monath), Ames, Iowa; Veristat LLC (Nowak), Southborough, Mass
| | - Catherine Brown
- Canadian Center for Vaccinology (ElSherif, Brown, MacKinnon-Cameron, Li, McNeil, Langley, Halperin), IWK Health Centre and Nova Scotia Health Authority, Dalhousie University, Halifax, NS; National Microbiology Laboratory (Racine, Alimonti), Winnipeg, Man.; Battelle Biomedical Research Center (Rudge, Sabourin), Columbus, Ohio; United States Army Medical Research Institute of Infectious Disease (Silvera, Hooper, Kwilas), Fort Detrick, Md.; Joint Program Executive Office for Chemical and Biological Defense Medical Countermeasure Systems' Joint Vaccine Acquisition Program (Kilgore, Badorrek), Fort Detrick, Md.; BioProtection Systems/NewLink Genetics Corporation (Ramsey, Heppner, Kemp, Monath), Ames, Iowa; Veristat LLC (Nowak), Southborough, Mass
| | - Donna MacKinnon-Cameron
- Canadian Center for Vaccinology (ElSherif, Brown, MacKinnon-Cameron, Li, McNeil, Langley, Halperin), IWK Health Centre and Nova Scotia Health Authority, Dalhousie University, Halifax, NS; National Microbiology Laboratory (Racine, Alimonti), Winnipeg, Man.; Battelle Biomedical Research Center (Rudge, Sabourin), Columbus, Ohio; United States Army Medical Research Institute of Infectious Disease (Silvera, Hooper, Kwilas), Fort Detrick, Md.; Joint Program Executive Office for Chemical and Biological Defense Medical Countermeasure Systems' Joint Vaccine Acquisition Program (Kilgore, Badorrek), Fort Detrick, Md.; BioProtection Systems/NewLink Genetics Corporation (Ramsey, Heppner, Kemp, Monath), Ames, Iowa; Veristat LLC (Nowak), Southborough, Mass
| | - Li Li
- Canadian Center for Vaccinology (ElSherif, Brown, MacKinnon-Cameron, Li, McNeil, Langley, Halperin), IWK Health Centre and Nova Scotia Health Authority, Dalhousie University, Halifax, NS; National Microbiology Laboratory (Racine, Alimonti), Winnipeg, Man.; Battelle Biomedical Research Center (Rudge, Sabourin), Columbus, Ohio; United States Army Medical Research Institute of Infectious Disease (Silvera, Hooper, Kwilas), Fort Detrick, Md.; Joint Program Executive Office for Chemical and Biological Defense Medical Countermeasure Systems' Joint Vaccine Acquisition Program (Kilgore, Badorrek), Fort Detrick, Md.; BioProtection Systems/NewLink Genetics Corporation (Ramsey, Heppner, Kemp, Monath), Ames, Iowa; Veristat LLC (Nowak), Southborough, Mass
| | - Trina Racine
- Canadian Center for Vaccinology (ElSherif, Brown, MacKinnon-Cameron, Li, McNeil, Langley, Halperin), IWK Health Centre and Nova Scotia Health Authority, Dalhousie University, Halifax, NS; National Microbiology Laboratory (Racine, Alimonti), Winnipeg, Man.; Battelle Biomedical Research Center (Rudge, Sabourin), Columbus, Ohio; United States Army Medical Research Institute of Infectious Disease (Silvera, Hooper, Kwilas), Fort Detrick, Md.; Joint Program Executive Office for Chemical and Biological Defense Medical Countermeasure Systems' Joint Vaccine Acquisition Program (Kilgore, Badorrek), Fort Detrick, Md.; BioProtection Systems/NewLink Genetics Corporation (Ramsey, Heppner, Kemp, Monath), Ames, Iowa; Veristat LLC (Nowak), Southborough, Mass
| | - Judie Alimonti
- Canadian Center for Vaccinology (ElSherif, Brown, MacKinnon-Cameron, Li, McNeil, Langley, Halperin), IWK Health Centre and Nova Scotia Health Authority, Dalhousie University, Halifax, NS; National Microbiology Laboratory (Racine, Alimonti), Winnipeg, Man.; Battelle Biomedical Research Center (Rudge, Sabourin), Columbus, Ohio; United States Army Medical Research Institute of Infectious Disease (Silvera, Hooper, Kwilas), Fort Detrick, Md.; Joint Program Executive Office for Chemical and Biological Defense Medical Countermeasure Systems' Joint Vaccine Acquisition Program (Kilgore, Badorrek), Fort Detrick, Md.; BioProtection Systems/NewLink Genetics Corporation (Ramsey, Heppner, Kemp, Monath), Ames, Iowa; Veristat LLC (Nowak), Southborough, Mass
| | - Thomas L Rudge
- Canadian Center for Vaccinology (ElSherif, Brown, MacKinnon-Cameron, Li, McNeil, Langley, Halperin), IWK Health Centre and Nova Scotia Health Authority, Dalhousie University, Halifax, NS; National Microbiology Laboratory (Racine, Alimonti), Winnipeg, Man.; Battelle Biomedical Research Center (Rudge, Sabourin), Columbus, Ohio; United States Army Medical Research Institute of Infectious Disease (Silvera, Hooper, Kwilas), Fort Detrick, Md.; Joint Program Executive Office for Chemical and Biological Defense Medical Countermeasure Systems' Joint Vaccine Acquisition Program (Kilgore, Badorrek), Fort Detrick, Md.; BioProtection Systems/NewLink Genetics Corporation (Ramsey, Heppner, Kemp, Monath), Ames, Iowa; Veristat LLC (Nowak), Southborough, Mass
| | - Carol Sabourin
- Canadian Center for Vaccinology (ElSherif, Brown, MacKinnon-Cameron, Li, McNeil, Langley, Halperin), IWK Health Centre and Nova Scotia Health Authority, Dalhousie University, Halifax, NS; National Microbiology Laboratory (Racine, Alimonti), Winnipeg, Man.; Battelle Biomedical Research Center (Rudge, Sabourin), Columbus, Ohio; United States Army Medical Research Institute of Infectious Disease (Silvera, Hooper, Kwilas), Fort Detrick, Md.; Joint Program Executive Office for Chemical and Biological Defense Medical Countermeasure Systems' Joint Vaccine Acquisition Program (Kilgore, Badorrek), Fort Detrick, Md.; BioProtection Systems/NewLink Genetics Corporation (Ramsey, Heppner, Kemp, Monath), Ames, Iowa; Veristat LLC (Nowak), Southborough, Mass
| | - Peter Silvera
- Canadian Center for Vaccinology (ElSherif, Brown, MacKinnon-Cameron, Li, McNeil, Langley, Halperin), IWK Health Centre and Nova Scotia Health Authority, Dalhousie University, Halifax, NS; National Microbiology Laboratory (Racine, Alimonti), Winnipeg, Man.; Battelle Biomedical Research Center (Rudge, Sabourin), Columbus, Ohio; United States Army Medical Research Institute of Infectious Disease (Silvera, Hooper, Kwilas), Fort Detrick, Md.; Joint Program Executive Office for Chemical and Biological Defense Medical Countermeasure Systems' Joint Vaccine Acquisition Program (Kilgore, Badorrek), Fort Detrick, Md.; BioProtection Systems/NewLink Genetics Corporation (Ramsey, Heppner, Kemp, Monath), Ames, Iowa; Veristat LLC (Nowak), Southborough, Mass
| | - Jay W Hooper
- Canadian Center for Vaccinology (ElSherif, Brown, MacKinnon-Cameron, Li, McNeil, Langley, Halperin), IWK Health Centre and Nova Scotia Health Authority, Dalhousie University, Halifax, NS; National Microbiology Laboratory (Racine, Alimonti), Winnipeg, Man.; Battelle Biomedical Research Center (Rudge, Sabourin), Columbus, Ohio; United States Army Medical Research Institute of Infectious Disease (Silvera, Hooper, Kwilas), Fort Detrick, Md.; Joint Program Executive Office for Chemical and Biological Defense Medical Countermeasure Systems' Joint Vaccine Acquisition Program (Kilgore, Badorrek), Fort Detrick, Md.; BioProtection Systems/NewLink Genetics Corporation (Ramsey, Heppner, Kemp, Monath), Ames, Iowa; Veristat LLC (Nowak), Southborough, Mass
| | - Steven A Kwilas
- Canadian Center for Vaccinology (ElSherif, Brown, MacKinnon-Cameron, Li, McNeil, Langley, Halperin), IWK Health Centre and Nova Scotia Health Authority, Dalhousie University, Halifax, NS; National Microbiology Laboratory (Racine, Alimonti), Winnipeg, Man.; Battelle Biomedical Research Center (Rudge, Sabourin), Columbus, Ohio; United States Army Medical Research Institute of Infectious Disease (Silvera, Hooper, Kwilas), Fort Detrick, Md.; Joint Program Executive Office for Chemical and Biological Defense Medical Countermeasure Systems' Joint Vaccine Acquisition Program (Kilgore, Badorrek), Fort Detrick, Md.; BioProtection Systems/NewLink Genetics Corporation (Ramsey, Heppner, Kemp, Monath), Ames, Iowa; Veristat LLC (Nowak), Southborough, Mass
| | - Nicole Kilgore
- Canadian Center for Vaccinology (ElSherif, Brown, MacKinnon-Cameron, Li, McNeil, Langley, Halperin), IWK Health Centre and Nova Scotia Health Authority, Dalhousie University, Halifax, NS; National Microbiology Laboratory (Racine, Alimonti), Winnipeg, Man.; Battelle Biomedical Research Center (Rudge, Sabourin), Columbus, Ohio; United States Army Medical Research Institute of Infectious Disease (Silvera, Hooper, Kwilas), Fort Detrick, Md.; Joint Program Executive Office for Chemical and Biological Defense Medical Countermeasure Systems' Joint Vaccine Acquisition Program (Kilgore, Badorrek), Fort Detrick, Md.; BioProtection Systems/NewLink Genetics Corporation (Ramsey, Heppner, Kemp, Monath), Ames, Iowa; Veristat LLC (Nowak), Southborough, Mass
| | - Christopher Badorrek
- Canadian Center for Vaccinology (ElSherif, Brown, MacKinnon-Cameron, Li, McNeil, Langley, Halperin), IWK Health Centre and Nova Scotia Health Authority, Dalhousie University, Halifax, NS; National Microbiology Laboratory (Racine, Alimonti), Winnipeg, Man.; Battelle Biomedical Research Center (Rudge, Sabourin), Columbus, Ohio; United States Army Medical Research Institute of Infectious Disease (Silvera, Hooper, Kwilas), Fort Detrick, Md.; Joint Program Executive Office for Chemical and Biological Defense Medical Countermeasure Systems' Joint Vaccine Acquisition Program (Kilgore, Badorrek), Fort Detrick, Md.; BioProtection Systems/NewLink Genetics Corporation (Ramsey, Heppner, Kemp, Monath), Ames, Iowa; Veristat LLC (Nowak), Southborough, Mass
| | - W Jay Ramsey
- Canadian Center for Vaccinology (ElSherif, Brown, MacKinnon-Cameron, Li, McNeil, Langley, Halperin), IWK Health Centre and Nova Scotia Health Authority, Dalhousie University, Halifax, NS; National Microbiology Laboratory (Racine, Alimonti), Winnipeg, Man.; Battelle Biomedical Research Center (Rudge, Sabourin), Columbus, Ohio; United States Army Medical Research Institute of Infectious Disease (Silvera, Hooper, Kwilas), Fort Detrick, Md.; Joint Program Executive Office for Chemical and Biological Defense Medical Countermeasure Systems' Joint Vaccine Acquisition Program (Kilgore, Badorrek), Fort Detrick, Md.; BioProtection Systems/NewLink Genetics Corporation (Ramsey, Heppner, Kemp, Monath), Ames, Iowa; Veristat LLC (Nowak), Southborough, Mass
| | - D Gray Heppner
- Canadian Center for Vaccinology (ElSherif, Brown, MacKinnon-Cameron, Li, McNeil, Langley, Halperin), IWK Health Centre and Nova Scotia Health Authority, Dalhousie University, Halifax, NS; National Microbiology Laboratory (Racine, Alimonti), Winnipeg, Man.; Battelle Biomedical Research Center (Rudge, Sabourin), Columbus, Ohio; United States Army Medical Research Institute of Infectious Disease (Silvera, Hooper, Kwilas), Fort Detrick, Md.; Joint Program Executive Office for Chemical and Biological Defense Medical Countermeasure Systems' Joint Vaccine Acquisition Program (Kilgore, Badorrek), Fort Detrick, Md.; BioProtection Systems/NewLink Genetics Corporation (Ramsey, Heppner, Kemp, Monath), Ames, Iowa; Veristat LLC (Nowak), Southborough, Mass
| | - Tracy Kemp
- Canadian Center for Vaccinology (ElSherif, Brown, MacKinnon-Cameron, Li, McNeil, Langley, Halperin), IWK Health Centre and Nova Scotia Health Authority, Dalhousie University, Halifax, NS; National Microbiology Laboratory (Racine, Alimonti), Winnipeg, Man.; Battelle Biomedical Research Center (Rudge, Sabourin), Columbus, Ohio; United States Army Medical Research Institute of Infectious Disease (Silvera, Hooper, Kwilas), Fort Detrick, Md.; Joint Program Executive Office for Chemical and Biological Defense Medical Countermeasure Systems' Joint Vaccine Acquisition Program (Kilgore, Badorrek), Fort Detrick, Md.; BioProtection Systems/NewLink Genetics Corporation (Ramsey, Heppner, Kemp, Monath), Ames, Iowa; Veristat LLC (Nowak), Southborough, Mass
| | - Thomas P Monath
- Canadian Center for Vaccinology (ElSherif, Brown, MacKinnon-Cameron, Li, McNeil, Langley, Halperin), IWK Health Centre and Nova Scotia Health Authority, Dalhousie University, Halifax, NS; National Microbiology Laboratory (Racine, Alimonti), Winnipeg, Man.; Battelle Biomedical Research Center (Rudge, Sabourin), Columbus, Ohio; United States Army Medical Research Institute of Infectious Disease (Silvera, Hooper, Kwilas), Fort Detrick, Md.; Joint Program Executive Office for Chemical and Biological Defense Medical Countermeasure Systems' Joint Vaccine Acquisition Program (Kilgore, Badorrek), Fort Detrick, Md.; BioProtection Systems/NewLink Genetics Corporation (Ramsey, Heppner, Kemp, Monath), Ames, Iowa; Veristat LLC (Nowak), Southborough, Mass
| | - Teresa Nowak
- Canadian Center for Vaccinology (ElSherif, Brown, MacKinnon-Cameron, Li, McNeil, Langley, Halperin), IWK Health Centre and Nova Scotia Health Authority, Dalhousie University, Halifax, NS; National Microbiology Laboratory (Racine, Alimonti), Winnipeg, Man.; Battelle Biomedical Research Center (Rudge, Sabourin), Columbus, Ohio; United States Army Medical Research Institute of Infectious Disease (Silvera, Hooper, Kwilas), Fort Detrick, Md.; Joint Program Executive Office for Chemical and Biological Defense Medical Countermeasure Systems' Joint Vaccine Acquisition Program (Kilgore, Badorrek), Fort Detrick, Md.; BioProtection Systems/NewLink Genetics Corporation (Ramsey, Heppner, Kemp, Monath), Ames, Iowa; Veristat LLC (Nowak), Southborough, Mass
| | - Shelly A McNeil
- Canadian Center for Vaccinology (ElSherif, Brown, MacKinnon-Cameron, Li, McNeil, Langley, Halperin), IWK Health Centre and Nova Scotia Health Authority, Dalhousie University, Halifax, NS; National Microbiology Laboratory (Racine, Alimonti), Winnipeg, Man.; Battelle Biomedical Research Center (Rudge, Sabourin), Columbus, Ohio; United States Army Medical Research Institute of Infectious Disease (Silvera, Hooper, Kwilas), Fort Detrick, Md.; Joint Program Executive Office for Chemical and Biological Defense Medical Countermeasure Systems' Joint Vaccine Acquisition Program (Kilgore, Badorrek), Fort Detrick, Md.; BioProtection Systems/NewLink Genetics Corporation (Ramsey, Heppner, Kemp, Monath), Ames, Iowa; Veristat LLC (Nowak), Southborough, Mass
| | - Joanne M Langley
- Canadian Center for Vaccinology (ElSherif, Brown, MacKinnon-Cameron, Li, McNeil, Langley, Halperin), IWK Health Centre and Nova Scotia Health Authority, Dalhousie University, Halifax, NS; National Microbiology Laboratory (Racine, Alimonti), Winnipeg, Man.; Battelle Biomedical Research Center (Rudge, Sabourin), Columbus, Ohio; United States Army Medical Research Institute of Infectious Disease (Silvera, Hooper, Kwilas), Fort Detrick, Md.; Joint Program Executive Office for Chemical and Biological Defense Medical Countermeasure Systems' Joint Vaccine Acquisition Program (Kilgore, Badorrek), Fort Detrick, Md.; BioProtection Systems/NewLink Genetics Corporation (Ramsey, Heppner, Kemp, Monath), Ames, Iowa; Veristat LLC (Nowak), Southborough, Mass
| | - Scott A Halperin
- Canadian Center for Vaccinology (ElSherif, Brown, MacKinnon-Cameron, Li, McNeil, Langley, Halperin), IWK Health Centre and Nova Scotia Health Authority, Dalhousie University, Halifax, NS; National Microbiology Laboratory (Racine, Alimonti), Winnipeg, Man.; Battelle Biomedical Research Center (Rudge, Sabourin), Columbus, Ohio; United States Army Medical Research Institute of Infectious Disease (Silvera, Hooper, Kwilas), Fort Detrick, Md.; Joint Program Executive Office for Chemical and Biological Defense Medical Countermeasure Systems' Joint Vaccine Acquisition Program (Kilgore, Badorrek), Fort Detrick, Md.; BioProtection Systems/NewLink Genetics Corporation (Ramsey, Heppner, Kemp, Monath), Ames, Iowa; Veristat LLC (Nowak), Southborough, Mass.
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Coller BAG, Blue J, Das R, Dubey S, Finelli L, Gupta S, Helmond F, Grant-Klein RJ, Liu K, Simon J, Troth S, VanRheenen S, Waterbury J, Wivel A, Wolf J, Heppner DG, Kemp T, Nichols R, Monath TP. Clinical development of a recombinant Ebola vaccine in the midst of an unprecedented epidemic. Vaccine 2017. [PMID: 28647166 DOI: 10.1016/j.vaccine.2017.05.097] [Citation(s) in RCA: 41] [Impact Index Per Article: 5.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
The 2014-2016 Ebola outbreak caused over 28,000 cases and 11,000 deaths. Merck & Co. Inc., Kenilworth, NJ USA and NewLink Genetics are working with private and public partners to develop and license an Ebola vaccine that was evaluated extensively during the outbreak. The vaccine referred to as V920 is a recombinant vesicular stomatitis virus (rVSV) in which the VSV-G envelope glycoprotein (GP) is completely replaced by the Zaire ebolavirus GP (rVSVΔG-ZEBOV-GP). Eight Phase I and four Phase II/III clinical trials enrolling approximately 17,000 subjects were conducted in parallel to the outbreak to assess the safety, immunogenicity, and/or efficacy of V920. Immunogenicity data demonstrate that anti-GP antibodies are generally detectable by ELISA by 14days postvaccination with up to 100% seroconversion observed by 28days post dose. In addition, the results of a ring vaccination trial conducted by the WHO and their partners in Guinea suggest robust vaccine efficacy within 10days of receipt of a single dose of vaccine. The vaccine is generally well-tolerated when administered to healthy, non-pregnant adults. The development of this vaccine candidate in the context of this unprecedented epidemic has involved the close cooperation of large number of international partners and highlights what we as a public health community can accomplish when working together towards a common goal. Study identification: V920-001 to V920-012. CLINICALTRIALS.GOV identifiers: NCT02269423; NCT02280408; NCT02374385; NCT02314923; NCT02287480; NCT02283099; NCT02296983; NCT02344407; NCT02378753; NCT02503202.
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Affiliation(s)
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | - D Gray Heppner
- NewLink Genetics, Inc./BioProtection Systems, Ames, IA, USA
| | - Tracy Kemp
- NewLink Genetics, Inc./BioProtection Systems, Ames, IA, USA
| | - Rick Nichols
- NewLink Genetics, Inc./BioProtection Systems, Ames, IA, USA
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Heppner DG, Kemp TL, Martin BK, Ramsey WJ, Nichols R, Dasen EJ, Link CJ, Das R, Xu ZJ, Sheldon EA, Nowak TA, Monath TP. Safety and immunogenicity of the rVSV∆G-ZEBOV-GP Ebola virus vaccine candidate in healthy adults: a phase 1b randomised, multicentre, double-blind, placebo-controlled, dose-response study. Lancet Infect Dis 2017; 17:854-866. [PMID: 28606591 DOI: 10.1016/s1473-3099(17)30313-4] [Citation(s) in RCA: 89] [Impact Index Per Article: 12.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/28/2016] [Revised: 04/07/2017] [Accepted: 04/10/2017] [Indexed: 10/19/2022]
Abstract
BACKGROUND The 2014 Zaire Ebola virus outbreak highlighted the need for a safe, effective vaccine with a rapid onset of protection. We report the safety and immunogenicity of the recombinant vesicular stomatitis virus-Zaire Ebola virus envelope glycoprotein vaccine (rVSV∆G-ZEBOV-GP) across a 6 log10 dose range in two sequential cohorts. METHODS In this phase 1b double-blind, placebo-controlled, dose-response study we enrolled and randomly assigned healthy adults (aged 18-61 years) at eight study sites in the USA to receive a single injection of vaccine or placebo, administered by intramuscular injection. In cohort 1, participants were assigned to receive 3 × 103, 3 × 104, 3 × 105, or 3 × 106 PFU doses of rVSV∆G-ZEBOV-GP or placebo. In cohort 2, participants were assigned to receive 3 × 106, 9 × 106, 2 × 107, or 1 × 108 PFU doses of rVSV∆G-ZEBOV-GP or placebo. Participants were centrally allocated by the study statistician to vaccine groups or placebo through computer-generated randomisation lists. The primary safety outcome was incidence of adverse events within 14 days in the modified intention-to-treat population (all randomly assigned participants who received vaccine or placebo), and the primary outcome for immunogenicity was IgG ELISA antibody titres at day 28 in the per-protocol population. Surveillance was enhanced for arthritis and dermatitis through to day 56. This study is registered with ClinicalTrials.gov, number NCT02314923. FINDINGS Between Dec 26, 2014, and June 8, 2015, 513 participants were enrolled and randomly assigned; one was not immunised because of unsuccessful phlebotomy. In cohort 1, 256 participants received vaccine (3 × 103 [n=64], 3 × 104 [n=64], 3 × 105 [n=64], or 3 × 106 PFU [n=64]) and 74 received placebo. In cohort 2, 162 participants received vaccine (3 × 106 [n=20], 9 × 106 [n=47], 2 × 107 [n=47], or 1 × 108 PFU [n=48]) and 20 received placebo. Most adverse events occurred in the first day after vaccination, and were mild to moderate in intensity, of a short duration, and more frequent at high vaccine doses (9 × 106 PFU and greater). At the 2 × 107 PFU dose (used in phase 3 trials), the most common local adverse events versus placebo within the first 14 days were arm pain (57·4% [27 of 47] vs 7·4% [seven of 94]) and local tenderness (59·6% [28 of 47] vs 8·5% [eight of 94]). The most common systemic adverse events at the 2 × 107 PFU dose versus placebo, occurring in the first 14 days, were headache (46·8% [22 of 47] vs 27·7% [26 of 94]), fatigue (38·3% [18 of 47] vs 19·1% [18 of 94]), myalgia (34·0% [16 of 47] vs 10·6% [10 of 94]), subjective fever (29·8% [14 of 47] vs 2·1% [two of 94]), shivering or chills (27·7% [13 of 47] vs 7·4% [seven of 94]), sweats (23·4% [11 of 47] vs 3·2% [three of 94]), joint aches and pain (19·1% [nine of 47] vs 7·4% [seven of 94]), objective fever (14·9% [seven of 47] vs 1·1% [one of 94]), and joint tenderness or swelling (14·9% [seven of 47] vs 2·1% [two of 94]). Self-limited, post-vaccination arthritis occurred in 4·5% (19 of 418) of vaccinees (median onset 12·0 days [IQR 10-14]; median duration 8·0 days [6-15]) versus 3·2% (three of 94) of controls (median onset 15·0 days [6-20]; median duration 47·0 days [37-339]), with no apparent dose relationship. Post-vaccination dermatitis occurred in 5·7% (24 of 418) of vaccinees (median onset 9·0 days [IQR 2-12]; median duration 7·0 days [4-9]) versus 3·2% (three of 94) of controls (median onset 5·0 days [3-53]; median duration 33·0 days [5-370]). A low-level, transient, dose-dependent viraemia occurred in concert with early reactogenicity. Antibody responses were observed in most participants by day 14. IgG and neutralising antibody titres were dose-related (p=0·0003 for IgG ELISA and p<0·0001 for the 60% plaque-reduction neutralisation test [PRNT60] by linear trend). On day 28 at the 2 × 107 PFU dose, the geometric mean IgG ELISA endpoint titre was 1624 (95% CI 1146-2302) and seroconversion was 95·7% (95% CI 85·5-98·8); the geometric mean neutralising antibody titre by PRNT60 was 250 (176-355) and seroconversion was 95·7% (85·5-98·8). These robust immunological responses were sustained for 1 year. INTERPRETATION rVSV∆G-ZEBOV-GP was well tolerated and stimulated a rapid onset of binding and neutralising antibodies, which were maintained through to day 360. The immunogenicity results support selection of the 2 × 107 PFU dose. FUNDING Biomedical Advanced Research and Development Authority, US Department of Health and Human Services.
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Affiliation(s)
- D Gray Heppner
- Bioprotection Systems, NewLink Genetics, Ames, IA, USA; Devens, MA, USA.
| | - Tracy L Kemp
- Bioprotection Systems, NewLink Genetics, Ames, IA, USA; Devens, MA, USA
| | - Brian K Martin
- Bioprotection Systems, NewLink Genetics, Ames, IA, USA; Devens, MA, USA
| | - William J Ramsey
- Bioprotection Systems, NewLink Genetics, Ames, IA, USA; Devens, MA, USA
| | - Richard Nichols
- Bioprotection Systems, NewLink Genetics, Ames, IA, USA; Devens, MA, USA
| | - Emily J Dasen
- Bioprotection Systems, NewLink Genetics, Ames, IA, USA; Devens, MA, USA
| | - Charles J Link
- Bioprotection Systems, NewLink Genetics, Ames, IA, USA; Devens, MA, USA
| | | | | | | | | | - Thomas P Monath
- Bioprotection Systems, NewLink Genetics, Ames, IA, USA; Devens, MA, USA
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Graves SF, Kouriba B, Diarra I, Daou M, Niangaly A, Coulibaly D, Keita Y, Laurens MB, Berry AA, Vekemans J, Ripley Ballou W, Lanar DE, Dutta S, Gray Heppner D, Soisson L, Diggs CL, Thera MA, Doumbo OK, Plowe CV, Sztein MB, Lyke KE. Strain-specific Plasmodium falciparum multifunctional CD4+ T cell cytokine expression in Malian children immunized with the FMP2.1/AS02A vaccine candidate. Vaccine 2016; 34:2546-55. [DOI: 10.1016/j.vaccine.2016.04.019] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/18/2015] [Revised: 03/24/2016] [Accepted: 04/07/2016] [Indexed: 12/17/2022]
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Talley AK, Healy SA, Finney OC, Murphy SC, Kublin J, Salas CJ, Lundebjerg S, Gilbert P, Van Voorhis WC, Whisler J, Wang R, Ockenhouse CF, Heppner DG, Kappe SH, Duffy PE. Safety and comparability of controlled human Plasmodium falciparum infection by mosquito bite in malaria-naïve subjects at a new facility for sporozoite challenge. PLoS One 2014; 9:e109654. [PMID: 25405724 PMCID: PMC4236046 DOI: 10.1371/journal.pone.0109654] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/10/2014] [Accepted: 08/30/2014] [Indexed: 12/18/2022] Open
Abstract
Background Controlled human malaria infection (CHMI) studies which recapitulate mosquito-borne infection are a critical tool to identify protective vaccine and drug candidates for advancement to field trials. In partnership with the Walter Reed Army Institute of Research, the CHMI model was established at the Seattle Biomedical Research Institute's Malaria Clinical Trials Center (MCTC). Activities and reagents at both centers were aligned to ensure comparability and continued safety of the model. To demonstrate successful implementation, CHMI was performed in six healthy malaria-naïve volunteers. Methods All volunteers received NF54 strain Plasmodium falciparum by the bite of five infected Anopheles stephensi mosquitoes under controlled conditions and were monitored for signs and symptoms of malaria and for parasitemia by peripheral blood smear. Subjects were treated upon diagnosis with chloroquine by directly observed therapy. Immunological (T cell and antibody) and molecular diagnostic (real-time quantitative reverse transcriptase polymerase chain reaction [qRT-PCR]) assessments were also performed. Results All six volunteers developed patent parasitemia and clinical malaria. No serious adverse events occurred during the study period or for six months post-infection. The mean prepatent period was 11.2 days (range 9–14 days), and geometric mean parasitemia upon diagnosis was 10.8 parasites/µL (range 2–69) by microscopy. qRT-PCR detected parasites an average of 3.7 days (range 2–4 days) earlier than blood smears. All volunteers developed antibodies to the blood-stage antigen merozoite surface protein 1 (MSP-1), which persisted up to six months. Humoral and cellular responses to pre-erythrocytic antigens circumsporozoite protein (CSP) and liver-stage antigen 1 (LSA-1) were limited. Conclusion The CHMI model was safe, well tolerated and characterized by consistent prepatent periods, pre-symptomatic diagnosis in 3/6 subjects and adverse event profiles as reported at established centers. The MCTC can now evaluate candidates in the increasingly diverse vaccine and drug pipeline using the CHMI model. Trial Registration ClinicalTrials.gov NCT01058226
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Affiliation(s)
- Angela K. Talley
- Malaria Clinical Trials Center, Seattle Biomedical Research Institute, Seattle, Washington, United States of America
| | - Sara A. Healy
- Laboratory for Malaria Immunology and Vaccinology, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Bethesda, Maryland, United States of America
| | - Olivia C. Finney
- Malaria Clinical Trials Center, Seattle Biomedical Research Institute, Seattle, Washington, United States of America
| | - Sean C. Murphy
- Department of Laboratory Medicine, University of Washington Medical Center, Seattle, Washington, United States of America
| | - James Kublin
- Fred Hutchinson Cancer Research Center, Seattle, Washington, United States of America
| | - Carola J. Salas
- United States Naval Medical Research Unit Number 6, Lima, Peru
| | - Susan Lundebjerg
- Malaria Clinical Trials Center, Seattle Biomedical Research Institute, Seattle, Washington, United States of America
| | - Peter Gilbert
- Fred Hutchinson Cancer Research Center, Seattle, Washington, United States of America
| | - Wesley C. Van Voorhis
- Department of Medicine, University of Washington Medical Center, Seattle, Washington, United States of America
| | - John Whisler
- Malaria Clinical Trials Center, Seattle Biomedical Research Institute, Seattle, Washington, United States of America
| | - Ruobing Wang
- Malaria Clinical Trials Center, Seattle Biomedical Research Institute, Seattle, Washington, United States of America
| | - Chris F. Ockenhouse
- United States Military Malaria Vaccine Program, Walter Reed Army Institute of Research, Silver Spring, Maryland, United States of America
| | - D. Gray Heppner
- United States Military Malaria Vaccine Program, Walter Reed Army Institute of Research, Silver Spring, Maryland, United States of America
| | - Stefan H. Kappe
- Malaria Clinical Trials Center, Seattle Biomedical Research Institute, Seattle, Washington, United States of America
| | - Patrick E. Duffy
- Laboratory for Malaria Immunology and Vaccinology, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Bethesda, Maryland, United States of America
- * E-mail:
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Kester KE, Gray Heppner D, Moris P, Ofori-Anyinam O, Krzych U, Tornieporth N, McKinney D, Delchambre M, Ockenhouse CF, Voss G, Holland C, Beckey JP, Ballou WR, Cohen J. Sequential Phase 1 and Phase 2 randomized, controlled trials of the safety, immunogenicity and efficacy of combined pre-erythrocytic vaccine antigens RTS,S and TRAP formulated with AS02 Adjuvant System in healthy, malaria naïve adults. Vaccine 2014; 32:6683-91. [PMID: 24950358 DOI: 10.1016/j.vaccine.2014.06.033] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/05/2013] [Revised: 05/26/2014] [Accepted: 06/06/2014] [Indexed: 10/25/2022]
Abstract
In an attempt to improve the efficacy of the candidate malaria vaccine RTS,S/AS02, two studies were conducted in 1999 in healthy volunteers of RTS,S/AS02 in combination with recombinant Plasmodium falciparum thrombospondin-related anonymous protein (TRAP). In a Phase 1 safety and immunogenicity study, volunteers were randomized to receive TRAP/AS02 (N=10), RTS,S/AS02 (N=10), or RTS,S+TRAP/AS02 (N=20) at 0, 1 and 6-months. In a Phase 2 challenge study, subjects were randomized to receive either RTS,S+TRAP/AS02 (N=25) or TRAP/AS02 (N=10) at 0 and 1-month, or to a challenge control group (N=8). In both studies, the combination vaccine had an acceptable safety profile and was acceptably tolerated. Antigen-specific antibodies, lymphoproliferative responses, and IFN-γ production by ELISPOT assay elicited with the combination vaccine were qualitatively similar to those generated by the single component vaccines. However, post-dose 2 anti-CS antibodies in the RTS,S+TRAP/AS02 vaccine recipients were lower than in the RTS,S/AS02 vaccine recipients. After challenge, 10 of 11 RTS,S+TRAP/AS02 vaccinees, 5 of 5 TRAP/AS02 vaccinees, and 8 of 8 infectivity controls developed parasitemia, with median pre-patent periods of 13.0, 11.0, and 12.0 days, respectively. The absence of any prevention or delay of parasitemia by TRAP/AS02 suggests no apparent added value of TRAP/AS02 as a candidate vaccine. The absence of significant protection or delay of parasitemia in the 11 RTS,S+TRAP/AS02 vaccine recipients contrasts with previous 2 dose studies of RTS,S/AS02. The small sample size did not permit identifying statistically significant differences between the study arms. However, we speculate, within the constraints of the challenge study, that the presence of the TRAP antigen may have interfered with the vaccine efficacy previously observed with this regimen of RTS,S/AS02, and that any future TRAP-based vaccines should consider employing alternative vaccine platforms.
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Affiliation(s)
- Kent E Kester
- Walter Reed Army Institute of Research, Silver Spring, MD, USA.
| | - D Gray Heppner
- Walter Reed Army Institute of Research, Silver Spring, MD, USA.
| | | | | | - Urszula Krzych
- Walter Reed Army Institute of Research, Silver Spring, MD, USA.
| | | | - Denise McKinney
- Walter Reed Army Institute of Research, Silver Spring, MD, USA.
| | | | | | - Gerald Voss
- GlaxoSmithKline Biologicals, Rixensart, Belgium.
| | - Carolyn Holland
- Walter Reed Army Institute of Research, Silver Spring, MD, USA.
| | | | - W Ripley Ballou
- Walter Reed Army Institute of Research, Silver Spring, MD, USA.
| | - Joe Cohen
- GlaxoSmithKline Biologicals, Rixensart, Belgium.
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Wolfe DN, Heppner DG, Gardner SN, Jaing C, Dupuy LC, Schmaljohn CS, Carlton K. Current strategic thinking for the development of a trivalent alphavirus vaccine for human use. Am J Trop Med Hyg 2014; 91:442-50. [PMID: 24842880 DOI: 10.4269/ajtmh.14-0055] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/05/2023] Open
Abstract
Vaccinations against the encephalitic alphaviruses (western, eastern, and Venezuelan equine encephalitis virus) are of significant interest to biological defense, public health, and agricultural communities alike. Although vaccines licensed for veterinary applications are used in the Western Hemisphere and attenuated or inactivated viruses have been used under Investigational New Drug status to protect at-risk personnel, there are currently no licensed vaccines for use in humans. Here, we will discuss the need for a trivalent vaccine that can protect humans against all three viruses, recent progress to such a vaccine, and a strategy to continue development to Food and Drug Administration licensure.
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Affiliation(s)
- Daniel N Wolfe
- Chemical and Biological Technologies Department, Defense Threat Reduction Agency, Fort Belvoir, Virginia; TASC, Inc., Lorton, Virginia; Computations/Global Security, Lawrence Livermore National Laboratory, Livermore, California; Physical and Life Sciences Directorate, Lawrence Livermore National Laboratory, Livermore, California; US Army Medical Research Institute for Infectious Diseases, Fort Detrick, Maryland; Joint Vaccine Acquisition Program, Medical Countermeasure Systems, Joint Program Executive Office, Fort Detrick, Maryland
| | - D Gray Heppner
- Chemical and Biological Technologies Department, Defense Threat Reduction Agency, Fort Belvoir, Virginia; TASC, Inc., Lorton, Virginia; Computations/Global Security, Lawrence Livermore National Laboratory, Livermore, California; Physical and Life Sciences Directorate, Lawrence Livermore National Laboratory, Livermore, California; US Army Medical Research Institute for Infectious Diseases, Fort Detrick, Maryland; Joint Vaccine Acquisition Program, Medical Countermeasure Systems, Joint Program Executive Office, Fort Detrick, Maryland
| | - Shea N Gardner
- Chemical and Biological Technologies Department, Defense Threat Reduction Agency, Fort Belvoir, Virginia; TASC, Inc., Lorton, Virginia; Computations/Global Security, Lawrence Livermore National Laboratory, Livermore, California; Physical and Life Sciences Directorate, Lawrence Livermore National Laboratory, Livermore, California; US Army Medical Research Institute for Infectious Diseases, Fort Detrick, Maryland; Joint Vaccine Acquisition Program, Medical Countermeasure Systems, Joint Program Executive Office, Fort Detrick, Maryland
| | - Crystal Jaing
- Chemical and Biological Technologies Department, Defense Threat Reduction Agency, Fort Belvoir, Virginia; TASC, Inc., Lorton, Virginia; Computations/Global Security, Lawrence Livermore National Laboratory, Livermore, California; Physical and Life Sciences Directorate, Lawrence Livermore National Laboratory, Livermore, California; US Army Medical Research Institute for Infectious Diseases, Fort Detrick, Maryland; Joint Vaccine Acquisition Program, Medical Countermeasure Systems, Joint Program Executive Office, Fort Detrick, Maryland
| | - Lesley C Dupuy
- Chemical and Biological Technologies Department, Defense Threat Reduction Agency, Fort Belvoir, Virginia; TASC, Inc., Lorton, Virginia; Computations/Global Security, Lawrence Livermore National Laboratory, Livermore, California; Physical and Life Sciences Directorate, Lawrence Livermore National Laboratory, Livermore, California; US Army Medical Research Institute for Infectious Diseases, Fort Detrick, Maryland; Joint Vaccine Acquisition Program, Medical Countermeasure Systems, Joint Program Executive Office, Fort Detrick, Maryland
| | - Connie S Schmaljohn
- Chemical and Biological Technologies Department, Defense Threat Reduction Agency, Fort Belvoir, Virginia; TASC, Inc., Lorton, Virginia; Computations/Global Security, Lawrence Livermore National Laboratory, Livermore, California; Physical and Life Sciences Directorate, Lawrence Livermore National Laboratory, Livermore, California; US Army Medical Research Institute for Infectious Diseases, Fort Detrick, Maryland; Joint Vaccine Acquisition Program, Medical Countermeasure Systems, Joint Program Executive Office, Fort Detrick, Maryland
| | - Kevin Carlton
- Chemical and Biological Technologies Department, Defense Threat Reduction Agency, Fort Belvoir, Virginia; TASC, Inc., Lorton, Virginia; Computations/Global Security, Lawrence Livermore National Laboratory, Livermore, California; Physical and Life Sciences Directorate, Lawrence Livermore National Laboratory, Livermore, California; US Army Medical Research Institute for Infectious Diseases, Fort Detrick, Maryland; Joint Vaccine Acquisition Program, Medical Countermeasure Systems, Joint Program Executive Office, Fort Detrick, Maryland
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12
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Abstract
It has been 40 years since David Clyde's landmark induction of sterile immunity against deadly falciparum malaria through immunization by exposure to 1000 irradiated mosquitoes, and the first recombinant Plasmodium falciparum vaccine, RTS,S/AS01, is now in Phase III testing. Interim reports from this largest ever Phase III pediatric trial in Africa show the malaria vaccine decreased clinical and severe disease by 56% and 47% respectively in 5-17 month olds, and by 31% and 26% respectively in infants participating in the Expanded Programme on Immunization. Final data in 2014 will more fully describe the efficacy of RTS,S/AS01 over time against all falciparum malaria cases under a variety of transmission conditions, results essential for decisions on licensure and deployment. Meanwhile, candidate components of a second-generation malaria vaccine are emerging. A field trial of the polymorphic blood stage vaccine AMA-1/AS02 demonstrated no overall efficacy (ve = 17%, P = 0.18), yet a sieve analysis revealed allele-specific efficacy (ve = 64%, P = 0.03) against the vaccine strain, suggesting AMA-1 antigens could be part of a multicomponent vaccine. Initial trials of new antigens include the highly conserved pre-erythrocytic candidate PfCelTOS, a synthetic Plasmodium vivax circumsporozoite antigen VMP-001, and sexual stage vaccines containing antigens from both P. falciparum (Pfs25) and P. vivax (Pvs25) intended to interrupt transmission. Targets for a vaccine to protect against placental malaria, the leading remediable cause of low birth weight infants in Africa, have been identified. Lastly, renewed efforts are underway to develop a practical attenuated-sporozoite vaccine to recapture the promise of David Clyde's experiment.
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Affiliation(s)
- D Gray Heppner
- Heppner Associates, LLC, 9441 Brenner Court, Vienna, VA 22180-3402, USA.
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13
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Otsyula N, Angov E, Bergmann-Leitner E, Koech M, Khan F, Bennett J, Otieno L, Cummings J, Andagalu B, Tosh D, Waitumbi J, Richie N, Shi M, Miller L, Otieno W, Otieno GA, Ware L, House B, Godeaux O, Dubois MC, Ogutu B, Ballou WR, Soisson L, Diggs C, Cohen J, Polhemus M, Heppner DG, Ockenhouse CF, Spring MD. Results from tandem Phase 1 studies evaluating the safety, reactogenicity and immunogenicity of the vaccine candidate antigen Plasmodium falciparum FVO merozoite surface protein-1 (MSP1(42)) administered intramuscularly with adjuvant system AS01. Malar J 2013; 12:29. [PMID: 23342996 PMCID: PMC3582548 DOI: 10.1186/1475-2875-12-29] [Citation(s) in RCA: 28] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/17/2012] [Accepted: 01/14/2013] [Indexed: 01/06/2023] Open
Abstract
Background The development of an asexual blood stage vaccine against Plasmodium falciparum malaria based on the major merozoite surface protein-1 (MSP1) antigen is founded on the protective efficacy observed in preclinical studies and induction of invasion and growth inhibitory antibody responses. The 42 kDa C-terminus of MSP1 has been developed as the recombinant protein vaccine antigen, and the 3D7 allotype, formulated with the Adjuvant System AS02A, has been evaluated extensively in human clinical trials. In preclinical rabbit studies, the FVO allele of MSP142 has been shown to have improved immunogenicity over the 3D7 allele, in terms of antibody titres as well as growth inhibitory activity of antibodies against both the heterologous 3D7 and homologous FVO parasites. Methods Two Phase 1 clinical studies were conducted to examine the safety, reactogenicity and immunogenicity of the FVO allele of MSP142 in the adjuvant system AS01 administered intramuscularly at 0-, 1-, and 2-months: one in the USA and, after evaluation of safety data results, one in Western Kenya. The US study was an open-label, dose escalation study of 10 and 50 μg doses of MSP142 in 26 adults, while the Kenya study, evaluating 30 volunteers, was a double-blind, randomized study of only the 50 μg dose with a rabies vaccine comparator. Results In these studies it was demonstrated that this vaccine formulation has an acceptable safety profile and is immunogenic in malaria-naïve and malaria-experienced populations. High titres of anti-MSP1 antibodies were induced in both study populations, although there was a limited number of volunteers whose serum demonstrated significant inhibition of blood-stage parasites as measured by growth inhibition assay. In the US volunteers, the antibodies generated exhibited better cross-reactivity to heterologous MSP1 alleles than a MSP1-based vaccine (3D7 allele) previously tested at both study sites. Conclusions Given that the primary effector mechanism for blood stage vaccine targets is humoral, the antibody responses demonstrated to this vaccine candidate, both quantitative (total antibody titres) and qualitative (functional antibodies inhibiting parasite growth) warrant further consideration of its application in endemic settings. Trial registrations Clinical Trials NCT00666380
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Affiliation(s)
- Nekoye Otsyula
- Walter Reed Project, Kenya Medical Research Institute, Kisumu, Kenya
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14
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Ouattara A, Takala-Harrison S, Thera MA, Coulibaly D, Niangaly A, Saye R, Tolo Y, Dutta S, Heppner DG, Soisson L, Diggs CL, Vekemans J, Cohen J, Blackwelder WC, Dube T, Laurens MB, Doumbo OK, Plowe CV. Molecular basis of allele-specific efficacy of a blood-stage malaria vaccine: vaccine development implications. J Infect Dis 2012. [PMID: 23204168 DOI: 10.1093/infdis/jis709] [Citation(s) in RCA: 59] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
Abstract
The disappointing efficacy of blood-stage malaria vaccines may be explained in part by allele-specific immune responses that are directed against polymorphic epitopes on blood-stage antigens. FMP2.1/AS02(A), a blood-stage candidate vaccine based on apical membrane antigen 1 (AMA1) from the 3D7 strain of Plasmodium falciparum, had allele-specific efficacy against clinical malaria in a phase II trial in Malian children. We assessed the cross-protective efficacy of the malaria vaccine and inferred which polymorphic amino acid positions in AMA1 were the targets of protective allele-specific immune responses. FMP2.1/AS02(A) had the highest efficacy against AMA1 alleles that were identical to the 3D7 vaccine-type allele at 8 highly polymorphic amino acid positions in the cluster 1 loop (c1L) but differed from 3D7 elsewhere in the molecule. Comparison of the incidence of vaccine-type alleles before and after vaccination in the malaria vaccine and control groups and examination of the patterns of allele change at polymorphic positions in consecutive malaria episodes suggest that the highly polymorphic amino acid position 197 in c1L was the most critical determinant of allele-specific efficacy. These results indicate that a multivalent AMA1 vaccine with broad efficacy could include only a limited set of key alleles of this extremely polymorphic antigen.
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Affiliation(s)
- Amed Ouattara
- Malaria Research and Training Center, University of Sciences, Techniques and Technology, Bamako, Mali
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15
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Schwenk R, Lumsden JM, Rein LE, Juompan L, Kester KE, Heppner DG, Krzych U. Immunization with the RTS,S/AS malaria vaccine induces IFN-γ(+)CD4 T cells that recognize only discrete regions of the circumsporozoite protein and these specificities are maintained following booster immunizations and challenge. Vaccine 2011; 29:8847-54. [PMID: 21983360 DOI: 10.1016/j.vaccine.2011.09.098] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/30/2011] [Revised: 09/14/2011] [Accepted: 09/25/2011] [Indexed: 10/17/2022]
Abstract
In a Phase 2a trial of the RTS,S/AS vaccine, we described significant association between protection against infection and vaccine-induced CD4 T cells. To determine whether processing of the circumsporozoite protein as a component of the RTS,S particulate antigen yields the same HLA-DR-restricted epitopes as those recognized by CD4 T cells from donors immunized by exposure to attenuated or infectious sporozoites we mapped the specificities of the RTS,S primed CD4 T cells by measuring IFN-γ cultured Elispot responses to pairs of overlapping 15 a.a. peptides that span the protein's C-terminus. Peptide pairs representing the previously described TH2R, T* and CS.T3 epitopes, were immunoprevalent and immunodominant. There was no response to the peptides corresponding to the human thrombospondin homology region. Responses to the CD4 T cell epitopes were restricted by multiple HLA-DR haplotypes. Of note, HLA-DR4 and HLA-DR11 restricted epitopes in the T* region and in the location on the CS protein defined by peptide pair 4, respectively. We conclude that processing of the CS protein derived from the RTS,S antigen leads to the generation of HLA-DR-restricted epitopes that are similar to those identified previously using CD4 T cells from subjects immunized with and protected by attenuated sporozoites or exposed to infectious sporozoites. This may in part account for the protective efficacy of the RTS,S/AS vaccine.
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Affiliation(s)
- Robert Schwenk
- Division of Malaria Vaccine Development, Walter Reed Army Institute of Research, Silver Spring, MD 20910, USA.
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16
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Thera MA, Doumbo OK, Coulibaly D, Laurens MB, Ouattara A, Kone AK, Guindo AB, Traore K, Traore I, Kouriba B, Diallo DA, Diarra I, Daou M, Dolo A, Tolo Y, Sissoko MS, Niangaly A, Sissoko M, Takala-Harrison S, Lyke KE, Wu Y, Blackwelder WC, Godeaux O, Vekemans J, Dubois MC, Ballou WR, Cohen J, Thompson D, Dube T, Soisson L, Diggs CL, House B, Lanar DE, Dutta S, Heppner DG, Plowe CV. A field trial to assess a blood-stage malaria vaccine. N Engl J Med 2011; 365:1004-13. [PMID: 21916638 PMCID: PMC3242358 DOI: 10.1056/nejmoa1008115] [Citation(s) in RCA: 275] [Impact Index Per Article: 21.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/07/2023]
Abstract
BACKGROUND Blood-stage malaria vaccines are intended to prevent clinical disease. The malaria vaccine FMP2.1/AS02(A), a recombinant protein based on apical membrane antigen 1 (AMA1) from the 3D7 strain of Plasmodium falciparum, has previously been shown to have immunogenicity and acceptable safety in Malian adults and children. METHODS In a double-blind, randomized trial, we immunized 400 Malian children with either the malaria vaccine or a control (rabies) vaccine and followed them for 6 months. The primary end point was clinical malaria, defined as fever and at least 2500 parasites per cubic millimeter of blood. A secondary end point was clinical malaria caused by parasites with the AMA1 DNA sequence found in the vaccine strain. RESULTS The cumulative incidence of the primary end point was 48.4% in the malaria-vaccine group and 54.4% in the control group; efficacy against the primary end point was 17.4% (hazard ratio for the primary end point, 0.83; 95% confidence interval [CI], 0.63 to 1.09; P=0.18). Efficacy against the first and subsequent episodes of clinical malaria, as defined on the basis of various parasite-density thresholds, was approximately 20%. Efficacy against clinical malaria caused by parasites with AMA1 corresponding to that of the vaccine strain was 64.3% (hazard ratio, 0.36; 95% CI, 0.08 to 0.86; P=0.03). Local reactions and fever after vaccination were more frequent with the malaria vaccine. CONCLUSIONS On the basis of the primary end point, the malaria vaccine did not provide significant protection against clinical malaria, but on the basis of secondary results, it may have strain-specific efficacy. If this finding is confirmed, AMA1 might be useful in a multicomponent malaria vaccine. (Funded by the National Institute of Allergy and Infectious Diseases and others; ClinicalTrials.gov number, NCT00460525.).
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Affiliation(s)
- Mahamadou A Thera
- Malaria Research and Training Center, University of Bamako, Bamako, Mali
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17
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Lumsden JM, Schwenk RJ, Rein LE, Moris P, Janssens M, Ofori-Anyinam O, Cohen J, Kester KE, Heppner DG, Krzych U. Protective immunity induced with the RTS,S/AS vaccine is associated with IL-2 and TNF-α producing effector and central memory CD4 T cells. PLoS One 2011; 6:e20775. [PMID: 21779319 PMCID: PMC3136919 DOI: 10.1371/journal.pone.0020775] [Citation(s) in RCA: 70] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/11/2011] [Accepted: 05/09/2011] [Indexed: 01/26/2023] Open
Abstract
A phase 2a RTS,S/AS malaria vaccine trial, conducted previously at the Walter Reed Army Institute of Research, conferred sterile immunity against a primary challenge with infectious sporozoites in 40% of the 80 subjects enrolled in the study. The frequency of Plasmodium falciparum circumsporozoite protein (CSP)-specific CD4(+) T cells was significantly higher in protected subjects as compared to non-protected subjects. Intrigued by these unique vaccine-related correlates of protection, in the present study we asked whether RTS,S also induced effector/effector memory (T(E/EM)) and/or central memory (T(CM)) CD4(+) T cells and whether one or both of these sub-populations is the primary source of cytokine production. We showed for the first time that PBMC from malaria-non-exposed RTS,S-immunized subjects contain both T(E/EM) and T(CM) cells that generate strong IL-2 responses following re-stimulation in vitro with CSP peptides. Moreover, both the frequencies and the total numbers of IL-2-producing CD4(+) T(E/EM) cells and of CD4(+) T(CM) cells from protected subjects were significantly higher than those from non-protected subjects. We also demonstrated for the first time that there is a strong association between the frequency of CSP peptide-reactive CD4(+) T cells producing IL-2 and the titers of CSP-specific antibodies in the same individual, suggesting that IL-2 may be acting as a growth factor for follicular Th cells and/or B cells. The frequencies of CSP peptide-reactive, TNF-α-producing CD4(+) T(E/EM) cells and of CD4(+) T(E/EM) cells secreting both IL-2 and TNF-α were also shown to be higher in protected vs. non-protected individuals. We have, therefore, demonstrated that in addition to TNF-α, IL-2 is also a significant contributing factor to RTS,S/AS vaccine induced immunity and that both T(E/EM) and T(CM) cells are major producers of IL-2.
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Affiliation(s)
- Joanne M. Lumsden
- Division of Malaria Vaccine Development, Walter Reed Army Institute of Research, Silver Spring, Maryland, United States of America
| | - Robert J. Schwenk
- Division of Malaria Vaccine Development, Walter Reed Army Institute of Research, Silver Spring, Maryland, United States of America
| | - Lisa E. Rein
- Division of Malaria Vaccine Development, Walter Reed Army Institute of Research, Silver Spring, Maryland, United States of America
| | | | | | | | - Joe Cohen
- GlaxoSmithKline Biologicals, Rixensart, Belgium
| | - Kent E. Kester
- Division of Malaria Vaccine Development, Walter Reed Army Institute of Research, Silver Spring, Maryland, United States of America
| | - D. Gray Heppner
- Division of Malaria Vaccine Development, Walter Reed Army Institute of Research, Silver Spring, Maryland, United States of America
| | - Urszula Krzych
- Division of Malaria Vaccine Development, Walter Reed Army Institute of Research, Silver Spring, Maryland, United States of America
- * E-mail:
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18
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Woodring JV, Ogutu B, Schnabel D, Waitumbi JN, Olsen CH, Walsh DS, Heppner DG, Polhemus ME. Evaluation of recurrent parasitemia after artemether-lumefantrine treatment for uncomplicated malaria in children in western Kenya. Am J Trop Med Hyg 2010; 83:458-64. [PMID: 20810804 DOI: 10.4269/ajtmh.2010.09-0403] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022] Open
Abstract
From April 2005 to April 2006, a phase 2 malaria vaccine trial in Kenya enrolled 400 children aged 12-47 months. Each received mixed supervised and unsupervised artemether-lumefantrine for uncomplicated malaria, using a standard six-dose regimen, by weight. Children were followed for detection of parasitemia and clinical malaria. A median of two negative malaria blood films occurred during every recurrent parasitemia (RP) episode, suggesting reinfection over late recrudescence. Median time to RP after starting artemether-lumefantrine was 37 days (36-38). Of 2,020 evaluable artemether-lumefantrine treatments, there were no RPs in 99% by day 14, 71% by day 28, and 41% by day 42. By World Health Organization standards, 71% of treatment courses had adequate responses. Although recrudescence in some cannot be ruled out, our cohort had a shorter median time to RP compared with other artemether-lumefantrine treatment studies. This underscores patient counseling on completing all treatment doses for optimal protection from RP.
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Affiliation(s)
- Joseph V Woodring
- Walter Reed Army Institute of Research, Silver Spring, Maryland, USA.
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19
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Vahey MT, Wang Z, Kester KE, Cummings J, Heppner DG, Nau ME, Ofori-Anyinam O, Cohen J, Coche T, Ballou WR, Ockenhouse CF. Expression of genes associated with immunoproteasome processing of major histocompatibility complex peptides is indicative of protection with adjuvanted RTS,S malaria vaccine. J Infect Dis 2010; 201:580-9. [PMID: 20078211 DOI: 10.1086/650310] [Citation(s) in RCA: 91] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/03/2022] Open
Abstract
BACKGROUND Patterns of expressed genes in the peripheral blood mononuclear cells of persons who were receiving RTS,S/AS01 or RTS,S/AS02 malaria vaccine and were undergoing experimental challenge with mosquito-borne falciparum malaria were examined to identify markers associated with protection. METHODS Thirty-nine vaccine recipients were assessed at study entry; on the day of the third vaccination; at 24 h, 72 h, and 2 weeks after vaccination; and on day 5 after challenge. Of 39 vaccine recipients, 13 were protected and 26 were not. Eleven vaccine recipients exhibited delayed onset of parasitemia. All infectivity control subjects developed parasitemia. Prediction analysis of microarrays identified genes corresponding with protection. Gene set enrichment analysis identified sets of genes associated with protection after the third vaccination and before challenge. RESULTS After the third vaccination and before challenge, differential expression of genes in the immunoproteasome pathway distinguished protected and nonprotected persons. At 5 days after challenge, differential expression of genes associated with programmed cell death distinguished between subjects protected and not protected from malaria blood-stage infection. CONCLUSIONS The up-regulation of genes associated with the efficient processing of major histocompatibility complex peptides suggests a potential role of the vaccine in conferring major histocompatibility complex class 1-mediated protection and may represent a useful surrogate marker of vaccine efficacy without the need for challenge.
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Affiliation(s)
- Maryanne T Vahey
- The Walter Reed Army Institute of Research, Silver Spring, Maryland 20403, USA.
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20
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Thera MA, Doumbo OK, Coulibaly D, Laurens MB, Kone AK, Guindo AB, Traore K, Sissoko M, Diallo DA, Diarra I, Kouriba B, Daou M, Dolo A, Baby M, Sissoko MS, Sagara I, Niangaly A, Traore I, Olotu A, Godeaux O, Leach A, Dubois MC, Ballou WR, Cohen J, Thompson D, Dube T, Soisson L, Diggs CL, Takala SL, Lyke KE, House B, Lanar DE, Dutta S, Heppner DG, Plowe CV. Safety and immunogenicity of an AMA1 malaria vaccine in Malian children: results of a phase 1 randomized controlled trial. PLoS One 2010; 5:e9041. [PMID: 20140214 PMCID: PMC2816207 DOI: 10.1371/journal.pone.0009041] [Citation(s) in RCA: 51] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/23/2009] [Accepted: 01/07/2010] [Indexed: 11/19/2022] Open
Abstract
BACKGROUND The objective was to evaluate the safety and immunogenicity of the AMA1-based malaria vaccine FMP2.1/AS02(A) in children exposed to seasonal falciparum malaria. METHODOLOGY/PRINCIPAL FINDINGS A Phase 1 double blind randomized controlled dose escalation trial was conducted in Bandiagara, Mali, West Africa, a rural town with intense seasonal transmission of Plasmodium falciparum malaria. The malaria vaccine FMP2.1/AS02(A) is a recombinant protein (FMP2.1) based on apical membrane antigen 1 (AMA1) from the 3D7 clone of P. falciparum, formulated in the Adjuvant System AS02(A). The comparator vaccine was a cell-culture rabies virus vaccine (RabAvert). One hundred healthy Malian children aged 1-6 years were recruited into 3 cohorts and randomized to receive either 10 microg FMP2.1 in 0.1 mL AS02(A), or 25 microg FMP2.1 in 0.25 mL AS02(A), or 50 microg FMP2.1 50 microg in 0.5 mL AS02(A), or rabies vaccine. Three doses of vaccine were given at 0, 1 and 2 months, and children were followed for 1 year. Solicited symptoms were assessed for 7 days and unsolicited symptoms for 30 days after each vaccination. Serious adverse events were assessed throughout the study. Transient local pain and swelling were common and more frequent in all malaria vaccine dosage groups than in the comparator group, but were acceptable to parents of participants. Levels of anti-AMA1 antibodies measured by ELISA increased significantly (at least 100-fold compared to baseline) in all 3 malaria vaccine groups, and remained high during the year of follow up. CONCLUSION/SIGNIFICANCE The FMP2.1/AS02(A) vaccine had a good safety profile, was well-tolerated, and induced high and sustained antibody levels in malaria-exposed children. This malaria vaccine is being evaluated in a Phase 2 efficacy trial in children at this site. TRIAL REGISTRATION ClinicalTrials.gov NCT00358332 [NCT00358332].
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Affiliation(s)
- Mahamadou A. Thera
- Malaria Research and Training Center, University of Bamako, Bamako, Mali
| | - Ogobara K. Doumbo
- Malaria Research and Training Center, University of Bamako, Bamako, Mali
| | - Drissa Coulibaly
- Malaria Research and Training Center, University of Bamako, Bamako, Mali
| | - Matthew B. Laurens
- Howard Hughes Medical Institute/Center for Vaccine Development, University of Maryland School of Medicine, Baltimore, Maryland, United States of America
| | - Abdoulaye K. Kone
- Malaria Research and Training Center, University of Bamako, Bamako, Mali
| | - Ando B. Guindo
- Malaria Research and Training Center, University of Bamako, Bamako, Mali
| | - Karim Traore
- Malaria Research and Training Center, University of Bamako, Bamako, Mali
| | - Mady Sissoko
- Malaria Research and Training Center, University of Bamako, Bamako, Mali
| | - Dapa A. Diallo
- Malaria Research and Training Center, University of Bamako, Bamako, Mali
| | - Issa Diarra
- Malaria Research and Training Center, University of Bamako, Bamako, Mali
| | - Bourema Kouriba
- Malaria Research and Training Center, University of Bamako, Bamako, Mali
| | - Modibo Daou
- Malaria Research and Training Center, University of Bamako, Bamako, Mali
| | - Amagana Dolo
- Malaria Research and Training Center, University of Bamako, Bamako, Mali
| | - Mounirou Baby
- Malaria Research and Training Center, University of Bamako, Bamako, Mali
| | | | - Issaka Sagara
- Malaria Research and Training Center, University of Bamako, Bamako, Mali
| | - Amadou Niangaly
- Malaria Research and Training Center, University of Bamako, Bamako, Mali
| | - Idrissa Traore
- Malaria Research and Training Center, University of Bamako, Bamako, Mali
| | - Ally Olotu
- GlaxoSmithKline Biologicals, Rixensart, Belgium
| | | | | | | | | | - Joe Cohen
- GlaxoSmithKline Biologicals, Rixensart, Belgium
| | - Darby Thompson
- EMMES Corporation, Rockville, Maryland, United States of America
| | - Tina Dube
- EMMES Corporation, Rockville, Maryland, United States of America
| | - Lorraine Soisson
- Malaria Vaccine Development Program, U.S. Agency for International Development, Washington, D.C., United States of America
| | - Carter L. Diggs
- Malaria Vaccine Development Program, U.S. Agency for International Development, Washington, D.C., United States of America
| | - Shannon L. Takala
- Howard Hughes Medical Institute/Center for Vaccine Development, University of Maryland School of Medicine, Baltimore, Maryland, United States of America
| | - Kirsten E. Lyke
- Howard Hughes Medical Institute/Center for Vaccine Development, University of Maryland School of Medicine, Baltimore, Maryland, United States of America
| | - Brent House
- Division of Malaria Vaccine Development, Walter Reed Army Institute of Research, Silver Spring, Maryland, United States of America
| | - David E. Lanar
- Division of Malaria Vaccine Development, Walter Reed Army Institute of Research, Silver Spring, Maryland, United States of America
| | - Sheetij Dutta
- Division of Malaria Vaccine Development, Walter Reed Army Institute of Research, Silver Spring, Maryland, United States of America
| | - D. Gray Heppner
- Division of Malaria Vaccine Development, Walter Reed Army Institute of Research, Silver Spring, Maryland, United States of America
| | - Christopher V. Plowe
- Howard Hughes Medical Institute/Center for Vaccine Development, University of Maryland School of Medicine, Baltimore, Maryland, United States of America
- * E-mail:
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Dutta S, Sullivan JS, Grady KK, Haynes JD, Komisar J, Batchelor AH, Soisson L, Diggs CL, Heppner DG, Lanar DE, Collins WE, Barnwell JW. High antibody titer against apical membrane antigen-1 is required to protect against malaria in the Aotus model. PLoS One 2009; 4:e8138. [PMID: 19997632 PMCID: PMC2780715 DOI: 10.1371/journal.pone.0008138] [Citation(s) in RCA: 69] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/07/2009] [Accepted: 10/23/2009] [Indexed: 11/19/2022] Open
Abstract
A Plasmodium falciparum 3D7 strain Apical Membrane Antigen-1 (AMA1) vaccine, formulated with AS02A adjuvant, slowed parasite growth in a recent Phase 1/2a trial, however sterile protection was not observed. We tested this AS02A, and a Montanide ISA720 (ISA) formulation of 3D7 AMA1 in Aotus monkeys. The 3D7 parasite does not invade Aotus erythrocytes, hence two heterologous strains, FCH/4 and FVO, were used for challenge, FCH/4 AMA1 being more homologous to 3D7 than FVO AMA1. Following three vaccinations, the monkeys were challenged with 50,000 FCH/4 or 10,000 FVO parasites. Three of the six animals in the AMA+ISA group were protected against FCH/4 challenge. One monkey did not become parasitemic, another showed only a short period of low level parasitemia that self-cured, and a third animal showed a delay before exhibiting its parasitemic phase. This is the first protection shown in primates with a recombinant P. falciparum AMA1 without formulation in Freund's complete adjuvant. No animals in the AMA+AS02A group were protected, but this group exhibited a trend towards reduced growth rate. A second group of monkeys vaccinated with AMA+ISA vaccine was not protected against FVO challenge, suggesting strain-specificity of AMA1-based protection. Protection against FCH/4 strain correlated with the quantity of induced antibodies, as the protected animals were the only ones to have in vitro parasite growth inhibitory activity of >70% at 1∶10 serum dilution; immuno-fluorescence titers >8,000; ELISA titers against full-length AMA1 >300,000 and ELISA titer against AMA1 domains1+2 >100,000. A negative correlation between log ELISA titer and day 11 cumulative parasitemia (Spearman rank r = −0.780, p value = 0.0001), further confirmed the relationship between antibody titer and protection. High titers of cross-strain inhibitory antibodies against AMA1 are therefore critical to confer solid protection, and the Aotus model can be used to down-select future AMA1 formulations, prior to advanced human trials.
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Affiliation(s)
- Sheetij Dutta
- Department of Epitope Mapping, Walter Reed Army Institute of Research, Silver Spring, Maryland, United States of America
- * E-mail: (SD); (JWB)
| | - JoAnn S. Sullivan
- Malaria Branch, Division of Parasitic Diseases, Centers for Disease Control and Prevention, Atlanta, Georgia, United States of America
| | - Katharine K. Grady
- Malaria Branch, Division of Parasitic Diseases, Centers for Disease Control and Prevention, Atlanta, Georgia, United States of America
| | - J. David Haynes
- Division of Malaria Vaccine Development, Walter Reed Army Institute of Research, Silver Spring, Maryland, United States of America
| | - Jack Komisar
- Division of Malaria Vaccine Development, Walter Reed Army Institute of Research, Silver Spring, Maryland, United States of America
| | - Adrian H. Batchelor
- Department of Epitope Mapping, Walter Reed Army Institute of Research, Silver Spring, Maryland, United States of America
| | - Lorraine Soisson
- Malaria Vaccine Development Program, United States Agency for International Development, Washington, D. C., United States of America
| | - Carter L. Diggs
- Malaria Vaccine Development Program, United States Agency for International Development, Washington, D. C., United States of America
| | - D. Gray Heppner
- Division of Malaria Vaccine Development, Walter Reed Army Institute of Research, Silver Spring, Maryland, United States of America
| | - David E. Lanar
- Division of Malaria Vaccine Development, Walter Reed Army Institute of Research, Silver Spring, Maryland, United States of America
| | - William E. Collins
- Malaria Branch, Division of Parasitic Diseases, Centers for Disease Control and Prevention, Atlanta, Georgia, United States of America
| | - John W. Barnwell
- Malaria Branch, Division of Parasitic Diseases, Centers for Disease Control and Prevention, Atlanta, Georgia, United States of America
- * E-mail: (SD); (JWB)
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Pichyangkul S, Tongtawe P, Kum-Arb U, Yongvanitchit K, Gettayacamin M, Hollingdale MR, Limsalakpetch A, Stewart VA, Lanar DE, Dutta S, Angov E, Ware LA, Bergmann-Leitner ES, House B, Voss G, Dubois MC, Cohen JD, Fukuda MM, Heppner DG, Miller RS. Evaluation of the safety and immunogenicity of Plasmodium falciparum apical membrane antigen 1, merozoite surface protein 1 or RTS,S vaccines with adjuvant system AS02A administered alone or concurrently in rhesus monkeys. Vaccine 2009; 28:452-62. [PMID: 19857448 DOI: 10.1016/j.vaccine.2009.10.022] [Citation(s) in RCA: 32] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/22/2008] [Revised: 09/29/2009] [Accepted: 10/07/2009] [Indexed: 11/15/2022]
Abstract
In an effort to broaden the immune response induced by the RTS,S/AS02(A),vaccine, we have evaluated the immunogenicity of the RTS,S antigen when combined with MSP1(42) and with AMA1, antigens derived from the asexual blood stage. The objectives of this study were (i) to determine whether MSP1(42) and AMA1 vaccines formulated with the AS02(A) Adjuvant System were safe and immunogenic in the rhesus monkey model; (ii) to investigate whether MSP1(42) or AMA1 induced immune interference to each other, or to RTS,S, when added singly or in combinations at a single injection site; (iii) in the event of immune interference, to determine if this could be reduced when antigens were administered at separate sites. We found that MSP1(42) and AMA1 were safe and immunogenic, eliciting antibodies, and Th1 and Th2 responses using IFN-gamma and IL-5 as markers. When malaria antigens were delivered together in one formulation, MSP1(42) and RTS,S reduced AMA1-specific antibody responses as measured by ELISA however, only MSP1(42) lowered parasite growth inhibitory activity of anti-AMA1 antibodies as measured by in vitro growth inhibition assay. Unlike RTS,S, MSP1(42) significantly reduced AMA1 IFN-gamma and IL-5 responses. MSP1(42) suppression of AMA1 IFN-gamma responses was not seen in animals receiving RTS,S+AMA1+MSP1(42) suggesting that RTS,S restored IFN-gamma responses. Conversely, AMA1 had no effect on MSP1(42) antibody and IFN-gamma and IL-5 responses. Neither AMA1 alone or combined with MSP1(42) affected RTS,S antibody or IFN-gamma and IL-5 responses. Immune interference by MSP1(42) on AMA1 antibody responses was also evident when AMA1, MSP1(42) and RTS,S were administered concurrently at separate sites. These results suggest that immune interference may be complex and should be considered for the design of multi-antigen, multi-stage vaccines against malaria.
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Affiliation(s)
- S Pichyangkul
- Department of Immunology and Medicine, Armed Forces Research Institute of Medical Sciences, Bangkok, Thailand.
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Kester KE, Cummings JF, Ofori-Anyinam O, Ockenhouse CF, Krzych U, Moris P, Schwenk R, Nielsen RA, Debebe Z, Pinelis E, Juompan L, Williams J, Dowler M, Stewart VA, Wirtz RA, Dubois MC, Lievens M, Cohen J, Ballou WR, Heppner DG. Randomized, double-blind, phase 2a trial of falciparum malaria vaccines RTS,S/AS01B and RTS,S/AS02A in malaria-naive adults: safety, efficacy, and immunologic associates of protection. J Infect Dis 2009; 200:337-46. [PMID: 19569965 DOI: 10.1086/600120] [Citation(s) in RCA: 396] [Impact Index Per Article: 26.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/03/2022] Open
Abstract
BACKGROUND To further increase the efficacy of malaria vaccine RTS,S/AS02A, we tested the RTS,S antigen formulated using the AS01B Adjuvant System (GlaxoSmithKline Biologicals). METHODS In a double-blind, randomized trial, 102 healthy volunteers were evenly allocated to receive RTS,S/AS01B or RTS,S/AS02A vaccine at months 0, 1, and 2 of the study, followed by malaria challenge. Protected vaccine recipients were rechallenged 5 months later. RESULTS RTS,S/AS01B and RTS,S/AS02A were well tolerated and were safe. The efficacy of RTS,S/AS01B and RTS,S/AS02A was 50% (95% confidence interval [CI], 32.9%-67.1%) and 32% (95% CI, 17.6%-47.6%), respectively. At the time of initial challenge, the RTS,S/AS01B group had greater circumsporozoite protein (CSP)-specific immune responses, including higher immunoglobulin (Ig) G titers, higher numbers of CSP-specific CD4(+) T cells expressing 2 activation markers (interleukin-2, interferon [IFN]-gamma, tumor necrosis factor-alpha, or CD40L), and more ex vivo IFN-gamma enzyme-linked immunospots (ELISPOTs) than did the RTS,S/AS02A group. Protected vaccine recipients had a higher CSP-specific IgG titer (geometric mean titer, 188 vs 73 mug/mL; P < .001), higher numbers of CSP-specific CD4(+) T cells per 10(6) CD4(+) T cells (median, 963 vs 308 CSP-specific CD4(+) T cells/10(6) CD4(+) T cells; P < .001), and higher numbers of ex vivo IFN-gamma ELISPOTs (mean, 212 vs 96 spots/million cells; P < .001). At rechallenge, 4 of 9 vaccine recipients in each group were still completely protected. CONCLUSIONS The RTS,S/AS01B malaria vaccine warrants comparative field trials with RTS,S/AS02A to determine the best formulation for the protection of children and infants. The association between complete protection and immune responses is a potential tool for further optimization of protection. Trial registration. ClinicalTrials.gov identifier NCT00075049.
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Affiliation(s)
- Kent E Kester
- Walter Reed Army Institute of Research, 503 Robert Grant Ave., Silver Spring, MD 20910, USA.
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Cummings JF, Spring MD, Schwenk RJ, Ockenhouse CF, Kester KE, Polhemus ME, Walsh DS, Yoon IK, Prosperi C, Juompan LY, Lanar DE, Krzych U, Hall BT, Ware LA, Stewart VA, Williams J, Dowler M, Nielsen RK, Hillier CJ, Giersing BK, Dubovsky F, Malkin E, Tucker K, Dubois MC, Cohen JD, Ballou WR, Heppner DG. Recombinant Liver Stage Antigen-1 (LSA-1) formulated with AS01 or AS02 is safe, elicits high titer antibody and induces IFN-gamma/IL-2 CD4+ T cells but does not protect against experimental Plasmodium falciparum infection. Vaccine 2009; 28:5135-44. [PMID: 19737527 DOI: 10.1016/j.vaccine.2009.08.046] [Citation(s) in RCA: 64] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/30/2008] [Revised: 08/12/2009] [Accepted: 08/14/2009] [Indexed: 10/20/2022]
Abstract
Plasmodium falciparum Liver Stage Antigen 1 (LSA-1) is a pre-erythrocytic stage antigen. Our LSA-1 vaccine candidate is a recombinant protein with full-length C- and N-terminal flanking domains and two of the 17 amino acid repeats from the central repeat region termed "LSA-NRC." We describe the first Phase I/II study of this recombinant LSA-NRC protein formulated with either the AS01 or AS02 adjuvant system. We conducted an open-label Phase I/II study. Thirty-six healthy malaria-naïve adults received one of four formulations by intra-deltoid injection on a 0 and 1 month schedule; low dose (LD) LSA-NRC/AS01:10microg LSA-NRC/0.5ml AS01 (n=5), high dose (HD) LSA-NRC/AS01: 50microg LSA-NRC/0.5ml AS01 (n=13); LD LSA-NRC/AS02: 10microg LSA-NRC/0.5ml AS02 (n=5) and HD LSA-NRC/AS02: 50microg LSA-NRC/0.5ml AS02 (n=13). Two weeks post-second immunization, the high dose vaccinees and 6 non-immunized infectivity controls underwent experimental malaria sporozoite challenge. The vaccines showed a reassuring safety profile but were moderately reactogenic. There were no serious adverse events. All subjects seroconverted after the first immunization. Following the second immunization, LSA-1-specific CD4+ T cells producing two cytokines (IL-2 and IFN-gamma) were found by intra-cellular staining in all subjects in the LD LSA-NRC/AS01B group and in 3 of 5 subjects in the LD LSA-NRC/AS02 group. In contrast, the HD LSA-NRC/AS01 and HD LSA-NRC/AS02 group subjects had fewer LSA-1-specific CD4+ T cells, and minimal to no IFN-gamma responses. There was no increase in LSA-1-specific CD8+ T cells found in any group. Per protocol, 22 high dose vaccinees, but no low dose vaccinees, underwent P. falciparum homologous malaria challenge (3D7 clone). All vaccinees became parasitemic and there was no delay in their pre-patent period versus controls (p=0.95). LSA-NRC/AS01 and LSA-NRC/AS02 elicited antigen-specific antibody and CD4+ T cell responses, but elicited no protective immunity. Although the optimal antigen dose of LSA-NRC may not have been selected for the challenge portion of the protocol, further vaccine development based upon LSA-1 should not be excluded and should include alternative vaccine platforms able to elicit additional effector mechanisms such as CD8+ T cells.
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Affiliation(s)
- James F Cummings
- Walter Reed Army Institute of Research, Silver Spring, MD 20910, USA.
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25
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Polhemus ME, Remich SA, Ogutu BR, Waitumbi JN, Otieno L, Apollo S, Cummings JF, Kester KE, Ockenhouse CF, Stewart A, Ofori-Anyinam O, Ramboer I, Cahill CP, Lievens M, Dubois MC, Demoitie MA, Leach A, Cohen J, Ballou WR, Heppner DG. Evaluation of RTS,S/AS02A and RTS,S/AS01B in adults in a high malaria transmission area. PLoS One 2009; 4:e6465. [PMID: 19649245 PMCID: PMC2714466 DOI: 10.1371/journal.pone.0006465] [Citation(s) in RCA: 99] [Impact Index Per Article: 6.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/17/2008] [Accepted: 04/21/2009] [Indexed: 11/18/2022] Open
Abstract
Background This study advances the clinical development of the RTS,S/AS01B candidate malaria vaccine to malaria endemic populations. As a primary objective it compares the safety and reactogenicity of RTS,S/AS01B to the more extensively evaluated RTS,S/AS02A vaccine. Methodology A Phase IIb, single centre, double-blind, controlled trial of 6 months duration with a subsequent 6 month single-blind follow-up conducted in Kisumu West District, Kenya between August 2005 and August 2006. 255 healthy adults aged 18 to 35 years were randomized (1∶1∶1) to receive 3 doses of RTS,S/AS02A, RTS,S/AS01B or rabies vaccine (Rabipur®; Chiron Behring GmbH) at months 0, 1, 2. The primary objective was the occurrence of severe (grade 3) solicited or unsolicited general (i.e. systemic) adverse events (AEs) during 7 days follow up after each vaccination. Principal Findings Both candidate vaccines had a good safety profile and were well tolerated. One grade 3 systemic AE occurred within 7 days of vaccination (RTS,S/AS01B group). No unsolicited AEs or SAEs were related to vaccine. A marked increase in anti-CS antibody GMTs was observed post Dose 2 of both RTS,S/AS01B (31.6 EU/mL [95% CI: 23.9 to 41.6]) and RTS,S/AS02A (16.7 EU/mL [95% CI: 12.9 to 21.7]). A further increase was observed post Dose 3 in both the RTS,S/AS01B (41.4 EU/mL [95% CI: 31.7 to 54.2]) and RTS,S/AS02A (21.4 EU/mL [95% CI: 16.0 to 28.7]) groups. Anti-CS antibody GMTs were significantly greater with RTS,S/AS01B compared to RTS,S/AS02A at all time points post Dose 2 and Dose 3. Both candidate vaccines produced strong anti-HBs responses. Vaccine efficacy in the RTS,S/AS01B group was 29.5% (95% CI: −15.4 to 56.9, p = 0.164) and in the RTS,S/AS02A group 31.7% (95% CI: −11.6 to 58.2, p = 0.128). Conclusions Both candidate malaria vaccines were well tolerated over a 12 month surveillance period. A more favorable immunogenicity profile was observed with RTS,S/AS01B than with RTS,S/AS02A. Trial Registration Clinicaltrials.gov NCT00197054
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26
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Kifude CM, Polhemus ME, Heppner DG, Withers MR, Ogutu BR, Waitumbi JN. Hb Kenya among Luo Adults and Young Children in Malaria Holoendemic Western Kenya: Screened by High Performance Liquid Chromatography and Confirmed By Polymerase Chain Reaction. Hemoglobin 2009; 31:401-8. [DOI: 10.1080/03630260701587638] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/22/2022]
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27
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Spring MD, Cummings JF, Ockenhouse CF, Dutta S, Reidler R, Angov E, Bergmann-Leitner E, Stewart VA, Bittner S, Juompan L, Kortepeter MG, Nielsen R, Krzych U, Tierney E, Ware LA, Dowler M, Hermsen CC, Sauerwein RW, de Vlas SJ, Ofori-Anyinam O, Lanar DE, Williams JL, Kester KE, Tucker K, Shi M, Malkin E, Long C, Diggs CL, Soisson L, Dubois MC, Ballou WR, Cohen J, Heppner DG. Phase 1/2a study of the malaria vaccine candidate apical membrane antigen-1 (AMA-1) administered in adjuvant system AS01B or AS02A. PLoS One 2009; 4:e5254. [PMID: 19390585 PMCID: PMC2669163 DOI: 10.1371/journal.pone.0005254] [Citation(s) in RCA: 163] [Impact Index Per Article: 10.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/30/2008] [Accepted: 03/23/2009] [Indexed: 11/19/2022] Open
Abstract
Background This Phase 1/2a study evaluated the safety, immunogenicity, and efficacy of an experimental malaria vaccine comprised of the recombinant Plasmodium falciparum protein apical membrane antigen-1 (AMA-1) representing the 3D7 allele formulated with either the AS01B or AS02A Adjuvant Systems. Methodology/Principal Findings After a preliminary safety evaluation of low dose AMA-1/AS01B (10 µg/0.5 mL) in 5 adults, 30 malaria-naïve adults were randomly allocated to receive full dose (50 µg/0.5 mL) of AMA-1/AS01B (n = 15) or AMA-1/AS02A (n = 15), followed by a malaria challenge. All vaccinations were administered intramuscularly on a 0-, 1-, 2-month schedule. All volunteers experienced transient injection site erythema, swelling and pain. Two weeks post-third vaccination, anti-AMA-1 Geometric Mean Antibody Concentrations (GMCs) with 95% Confidence Intervals (CIs) were high: low dose AMA-1/AS01B 196 µg/mL (103–371 µg/mL), full dose AMA-1/AS01B 279 µg/mL (210–369 µg/mL) and full dose AMA-1/AS02A 216 µg/mL (169–276 µg/mL) with no significant difference among the 3 groups. The three vaccine formulations elicited equivalent functional antibody responses, as measured by growth inhibition assay (GIA), against homologous but not against heterologous (FVO) parasites as well as demonstrable interferon-gamma (IFN-γ) responses. To assess efficacy, volunteers were challenged with P. falciparum-infected mosquitoes, and all became parasitemic, with no significant difference in the prepatent period by either light microscopy or quantitative polymerase chain reaction (qPCR). However, a small but significant reduction of parasitemia in the AMA-1/AS02A group was seen with a statistical model employing qPCR measurements. Significance All three vaccine formulations were found to be safe and highly immunogenic. These immune responses did not translate into significant vaccine efficacy in malaria-naïve adults employing a primary sporozoite challenge model, but encouragingly, estimation of parasite growth rates from qPCR data may suggest a partial biological effect of the vaccine. Further evaluation of the immunogenicity and efficacy of the AMA-1/AS02A formulation is ongoing in a malaria-experienced pediatric population in Mali. Trial Registration www.clinicaltrials.govNCT00385047
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Affiliation(s)
- Michele D Spring
- United States Military Malaria Vaccine Program, Walter Reed Army Institute of Research, Silver Spring, Maryland, United States of America.
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28
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Ogutu BR, Apollo OJ, McKinney D, Okoth W, Siangla J, Dubovsky F, Tucker K, Waitumbi JN, Diggs C, Wittes J, Malkin E, Leach A, Soisson LA, Milman JB, Otieno L, Holland CA, Polhemus M, Remich SA, Ockenhouse CF, Cohen J, Ballou WR, Martin SK, Angov E, Stewart VA, Lyon JA, Heppner DG, Withers MR. Blood stage malaria vaccine eliciting high antigen-specific antibody concentrations confers no protection to young children in Western Kenya. PLoS One 2009; 4:e4708. [PMID: 19262754 PMCID: PMC2650803 DOI: 10.1371/journal.pone.0004708] [Citation(s) in RCA: 224] [Impact Index Per Article: 14.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/07/2008] [Accepted: 01/05/2009] [Indexed: 11/19/2022] Open
Abstract
Objective The antigen, falciparum malaria protein 1 (FMP1), represents the 42-kDa C-terminal fragment of merozoite surface protein-1 (MSP-1) of the 3D7 clone of P. falciparum. Formulated with AS02 (a proprietary Adjuvant System), it constitutes the FMP1/AS02 candidate malaria vaccine. We evaluated this vaccine's safety, immunogenicity, and efficacy in African children. Methods A randomised, double-blind, Phase IIb, comparator-controlled trial.The trial was conducted in 13 field stations of one mile radii within Kombewa Division, Nyanza Province, Western Kenya, an area of holoendemic transmission of P. falciparum. We enrolled 400 children aged 12–47 months in general good health.Children were randomised in a 1∶1 fashion to receive either FMP1/AS02 (50 µg) or Rabipur® rabies vaccine. Vaccinations were administered on a 0, 1, and 2 month schedule. The primary study endpoint was time to first clinical episode of P. falciparum malaria (temperature ≥37.5°C with asexual parasitaemia of ≥50,000 parasites/µL of blood) occurring between 14 days and six months after a third dose. Case detection was both active and passive. Safety and immunogenicity were evaluated for eight months after first immunisations; vaccine efficacy (VE) was measured over a six-month period following third vaccinations. Results 374 of 400 children received all three doses and completed six months of follow-up. FMP1/AS02 had a good safety profile and was well-tolerated but more reactogenic than the comparator. Geometric mean anti-MSP-142 antibody concentrations increased from1.3 µg/mL to 27.3 µg/mL in the FMP1/AS02 recipients, but were unchanged in controls. 97 children in the FMP1/AS02 group and 98 controls had a primary endpoint episode. Overall VE was 5.1% (95% CI: −26% to +28%; p-value = 0.7). Conclusions FMP1/AS02 is not a promising candidate for further development as a monovalent malaria vaccine. Future MSP-142 vaccine development should focus on other formulations and antigen constructs. Trial Registration Clinicaltrials.gov NCT00223990
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Affiliation(s)
- Bernhards R Ogutu
- US Army Medical Research Unit-Kenya and the Centre for Clinical Research, Kenya Medical Research Institute, Nairobi, Kenya.
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29
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Lyke KE, Daou M, Diarra I, Kone A, Kouriba B, Thera MA, Dutta S, Lanar DE, Heppner DG, Doumbo OK, Plowe CV, Sztein MB. Cell-mediated immunity elicited by the blood stage malaria vaccine apical membrane antigen 1 in Malian adults: results of a Phase I randomized trial. Vaccine 2009; 27:2171-6. [PMID: 19356621 DOI: 10.1016/j.vaccine.2009.01.097] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/06/2008] [Revised: 01/19/2009] [Accepted: 01/22/2009] [Indexed: 10/21/2022]
Abstract
The development of a safe and effective malaria vaccine is impeded by the complexity of the Plasmodium life cycle. A vaccine that elicits both cell-mediated and humoral immune responses might be needed for protection against this multistage parasitic infection. Apical membrane antigen 1 (AMA-1) plays a key role in erythrocytic invasion but is also expressed in sporozoites and in late stage liver schizonts, where it may provide a target of protective cell-mediated immunity (CMI). A Phase 1 trial of a vaccine consisting of recombinant AMA-1 protein and the Adjuvant system AS02A was conducted in 60 Malian adults aged 18-55 years who were randomized to receive either half-dose (25 microg/0.25 ml) or full dose (50 microg/0.5 ml) FMP2.1/AS02A or a control rabies vaccine. Interleukin 5 (IL-5) and interferon-gamma (IFN-gamma) production as evaluated by ELISpot and lymphocyte proliferation were measured after in vitro AMA-1 stimulation of peripheral blood mononuclear cells (PBMCs) collected on Days 0 and 90. Post-FMP2.1/AS02A immunization mean stimulation indices were significantly elevated as were the number of IL-5 spot forming cells (SFC)/10(6) PBMC, but no difference was noted in INF-gamma production between the AMA-1/AS02A vaccinated group and the rabies group. These results provide evidence that complex immune responses can be induced by this vaccination strategy and add further impetus for the continuing clinical evaluation of this vaccine.
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Affiliation(s)
- Kirsten E Lyke
- Center for Vaccine Development, University of Maryland, Baltimore, MD, United States.
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30
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Kester KE, Cummings JF, Ockenhouse CF, Nielsen R, Hall BT, Gordon DM, Schwenk RJ, Krzych U, Holland CA, Richmond G, Dowler MG, Williams J, Wirtz RA, Tornieporth N, Vigneron L, Delchambre M, Demoitie MA, Ballou WR, Cohen J, Heppner DG. Phase 2a trial of 0, 1, and 3 month and 0, 7, and 28 day immunization schedules of malaria vaccine RTS,S/AS02 in malaria-naïve adults at the Walter Reed Army Institute of Research. Vaccine 2008; 26:2191-202. [PMID: 18387719 DOI: 10.1016/j.vaccine.2008.02.048] [Citation(s) in RCA: 108] [Impact Index Per Article: 6.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/13/2007] [Revised: 02/14/2008] [Accepted: 02/22/2008] [Indexed: 11/17/2022]
Abstract
BACKGROUND Immunization with RTS,S/AS02 consistently protects some vaccinees against malaria infection in experimental challenges and in field trials. A brief immunization schedule against falciparum malaria would be compatible with the Expanded Programme on Immunization, or in combination with other prevention measures, interrupt epidemic malaria or protect individuals upon sudden travel to an endemic area. METHODS We conducted an open label, Phase 2a trial of two different full dose schedules of RTS,S/AS02 in 40 healthy malaria-naïve adults. Cohort 1 (n=20) was immunized on a 0, 1, and 3 month schedule and Cohort 2 (n=20) on a 0, 7, and 28 day schedule. Three weeks later, 38 vaccinees and 12 unimmunized infectivity controls underwent malaria challenge. RESULTS Both regimens had a good safety and tolerability profile. Peak GMCs of antibody to the circumsporozoite protein (CSP) were similar in Cohort 1 (78 microg/mL; 95% CI: 45-134) and Cohort 2 (65 microg/mL; 95% CI: 40-104). Vaccine efficacy for Cohort 1 was 45% (95% CI: 18-62%) and for Cohort 2, 39% (95% CI: 11-56%). Protected volunteers had a higher GMC of anti-CSP antibody (114 microg/mL) than did volunteers with a 2-day delay (70 microg/mL) or no delay (30 microg/mL) in the time to onset of parasitemia (Kruskal-Wallis, p=0.019). A trend was seen for higher CSP-specific IFN-gamma responses in PBMC from protected volunteers only in Cohort 1, but not in Cohort 2, for ex vivo and for cultured ELISPOT assays. CONCLUSION In malaria-naïve adults, the efficacy of three-dose RTS,S/AS02 regimens on either a 0, 1, and 3 month schedule or an abbreviated 0, 7, and 28 day schedule was not discernibly different from two previously reported trials of two-dose regimens given at 0, 1 month that conferred 47% (95% CI: -19 to 76%) protection and in another trial 42% (95% CI: 5-63%). A strong association of CSP-specific antibody with protection against malaria challenge is observed and confirms similar observations made in other studies. Subsequent trials of adjuvanted RTS,S in African children and infants on a 0, 1, and 2 month schedule have demonstrated a favorable safety and efficacy profile.
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Affiliation(s)
- Kent E Kester
- Walter Reed Army Institute of Research, 503 Robert Grant Avenue, Silver Spring, MD 20910, USA.
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Waitumbi JN, Kifude CM, Withers MR, Polhemus ME, Heppner DG, Ogutu BR. Hb G-Philadelphia or Stanleyville II? When the phenotype and genotype do not agree. Eur J Haematol 2007; 79:177-8. [PMID: 17608715 DOI: 10.1111/j.1600-0609.2007.00879.x] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
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Heppner DG, Schwenk RJ, Arnot D, Sauerwein RW, Luty AJF. The dog that did not bark: malaria vaccines without antibodies. Trends Parasitol 2007; 23:293-6. [PMID: 17512252 DOI: 10.1016/j.pt.2007.05.002] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/17/2006] [Revised: 03/20/2007] [Accepted: 05/03/2007] [Indexed: 01/29/2023]
Abstract
To date, the only pre-blood stage vaccine to confer protection against malaria in field trials elicits both antigen-specific antibody and T-cell responses. Recent clinical trials of new heterologous prime-boost malaria vaccine regimens using DNA, fowlpox or MVA, have chiefly elicited T-cell responses that have promisingly reduced hepatic merozoites in challenge trials, but failed to protect in field trials. These encouraging results suggest further augmentation of T-cell responses to pre-blood stage antigens might one day contribute to a highly protective vaccine. We envision that a highly protective pre-erythrocytic vaccine will likely be based upon a heterologous prime-boost regimen that induces both appropriate T-cell responses as well as robust and protracted antibody production.
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Affiliation(s)
- D Gray Heppner
- Walter Reed Army Institute of Research, 503 Robert Grant Avenue, Silver Spring, MD 20910, USA
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33
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Kester KE, McKinney DA, Tornieporth N, Ockenhouse CF, Heppner DG, Hall T, Wellde BT, White K, Sun P, Schwenk R, Krzych U, Delchambre M, Voss G, Dubois MC, Gasser RA, Dowler MG, O'Brien M, Wittes J, Wirtz R, Cohen J, Ballou WR. A phase I/IIa safety, immunogenicity, and efficacy bridging randomized study of a two-dose regimen of liquid and lyophilized formulations of the candidate malaria vaccine RTS,S/AS02A in malaria-naïve adults. Vaccine 2007; 25:5359-66. [PMID: 17574311 DOI: 10.1016/j.vaccine.2007.05.005] [Citation(s) in RCA: 86] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/04/2006] [Revised: 05/05/2007] [Accepted: 05/09/2007] [Indexed: 11/20/2022]
Abstract
We conducted an open-label safety and immunogenicity bridging study that compared liquid and lyophilized formulations of the candidate malaria vaccine RTS,S formulated in AS02A in 34 healthy, malaria-naïve adults at WRAIR. Volunteers received two doses of either formulation on a 0, 1-month schedule. Both vaccines were well tolerated and similarly immunogenic. Nineteen of 25 subjects who received the lyophilized formulation and six infectivity controls underwent sporozoite challenge to assess vaccine efficacy. All six controls had parasitemia detectable by thick blood smear by day 13 (mean pre-patent period 12.3 days; range 11-13). In the vaccine group, 8 of 19 vaccinees did not develop malaria and were completely protected (i.e., 42%). Among the 11 vaccinees who did become infected, the mean pre-patent period was delayed (14.4 days; range 13-18). The two formulations of RTS,S were equally safe and immunogenic, and the lyophilized formulation showed similar levels of efficacy against sporozoite challenge to that conferred by the liquid formulation in previous studies.
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Affiliation(s)
- Kent E Kester
- Walter Reed Army Institute of Research, 503 Robert Grant Avenue, Silver Spring, MD 20910, USA.
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Polhemus ME, Magill AJ, Cummings JF, Kester KE, Ockenhouse CF, Lanar DE, Dutta S, Barbosa A, Soisson L, Diggs CL, Robinson SA, Haynes JD, Stewart VA, Ware LA, Brando C, Krzych U, Bowden RA, Cohen JD, Dubois MC, Ofori-Anyinam O, De-Kock E, Ballou WR, Heppner DG. Phase I dose escalation safety and immunogenicity trial of Plasmodium falciparum apical membrane protein (AMA-1) FMP2.1, adjuvanted with AS02A, in malaria-naïve adults at the Walter Reed Army Institute of Research. Vaccine 2007; 25:4203-12. [PMID: 17442466 DOI: 10.1016/j.vaccine.2007.03.012] [Citation(s) in RCA: 78] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/11/2006] [Revised: 02/21/2007] [Accepted: 03/02/2007] [Indexed: 11/26/2022]
Abstract
We report the first safety and immunogenicity trial of the Plasmodium falciparum vaccine candidate FMP2.1/AS02A, a recombinant E. coli-expressed protein based upon the apical membrane antigen-1 (AMA-1) of the 3D7 clone formulated with the AS02A adjuvant. We conducted an open-label, staggered-start, dose-escalating Phase I trial in 23 malaria-naïve volunteers who received 8, 20 or 40microg of FMP2.1 in a fixed volume of 0.5mL of AS02A on a 0, 1, and 2 month schedule. Nineteen of 23 volunteers received all three scheduled immunizations. The most frequent solicited local and systemic adverse events associated with immunization were injection site pain (68%) and headache (29%). There were no significant laboratory abnormalities or vaccine-related serious adverse events. All volunteers seroconverted after second immunization as determined by ELISA. Immune sera recognized sporozoites and merozoites by immunofluorescence assay (IFA), and exhibited both growth inhibition and processing inhibition activity against homologous (3D7) asexual stage parasites. Post-immunization, peripheral blood mononuculear cells exhibited FMP2.1-specific lymphoproliferation and IFN-gamma and IL-5 ELISPOT assay responses. This is the first PfAMA-1-based vaccine shown to elicit both potent humoral and cellular immunity in humans. Encouraged by the potential of FMP1/AS02A to target host immunity against PfAMA-1 that is known to be expressed by sporozoite, hepatic and erythrocytic stages, we have initiated field trials of FMP2.1/AS02A in an endemic population in the Republic of Mali.
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Affiliation(s)
- Mark E Polhemus
- Walter Reed Army Institute of Research, Silver Spring, MD, United States.
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35
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Macete E, Aponte JJ, Guinovart C, Sacarlal J, Ofori-Anyinam O, Mandomando I, Espasa M, Bevilacqua C, Leach A, Dubois MC, Heppner DG, Tello L, Milman J, Cohen J, Dubovsky F, Tornieporth N, Thompson R, Alonso PL. Safety and immunogenicity of the RTS,S/AS02A candidate malaria vaccine in children aged 1-4 in Mozambique. Trop Med Int Health 2007; 12:37-46. [PMID: 17207146 DOI: 10.1111/j.1365-3156.2006.01754.x] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
BACKGROUND The development of a malaria vaccine remains a public health priority for sub-Saharan Africa. RTS,S/AS02A candidate malaria vaccine has been shown to be safe and immunogenic in previous studies in adults and staggered dose-escalation studies in children in The Gambia. However, genetic features and the intensity of malaria transmission may modify the safety and immune response of a vaccine. OBJECTIVE We carried out a phase I, double-blind randomized controlled trial in 60 children aged 1-4 in Mozambique to evaluate the safety, reactogenicity and immunogenicity of the paediatric vaccine dose (fixed 25 microg RTS,S in 0.25 ml) of RTS,S/AS02A, prior to undertaking a planned larger phase IIb proof-of-concept of efficacy study in the same population. METHOD Children were randomized to receive either RTS,S/AS02A or Engerix-B vaccine. Monitoring of safety and reactogenicity included detailed clinical and laboratory analyses and assessment of adverse events (AEs). RESULTS The RTS,S/AS02A was found to be safe and well tolerated. Serious adverse events were balanced between both groups and none was related to vaccination. The frequency of adverse events reported with RTS, S/AS02A was comparable to previous studies in children. Grade 3 AEs were infrequent (one case of pain, one of fever in each group and some swelling greater than 20 mm in diameter), transient and resolved without sequelae. RTS,S/AS02A was highly immunogenic for anti-circumsporozoite protein antibody response and induced a strong anti-hepatitis-B surface antigen response.
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Affiliation(s)
- E Macete
- Centro de Investigação em Saúde da Manhiça (CISM), Manhiça, Mozambique
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36
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Stewart VA, McGrath SM, Dubois PM, Pau MG, Mettens P, Shott J, Cobb M, Burge JR, Larson D, Ware LA, Demoitie MA, Weverling GJ, Bayat B, Custers JHHV, Dubois MC, Cohen J, Goudsmit J, Heppner DG. Priming with an adenovirus 35-circumsporozoite protein (CS) vaccine followed by RTS,S/AS01B boosting significantly improves immunogenicity to Plasmodium falciparum CS compared to that with either malaria vaccine alone. Infect Immun 2007; 75:2283-90. [PMID: 17307942 PMCID: PMC1865796 DOI: 10.1128/iai.01879-06] [Citation(s) in RCA: 90] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
The RTS,S/AS02A protein-based vaccine consistently demonstrates significant protection against infection with Plasmodium falciparum malaria and also against clinical malaria and severe disease in children in areas of endemicity. Here we demonstrate with rhesus macaques that priming with a replication-defective human adenovirus serotype 35 (Ad35) vector encoding circumsporozoite protein (CS) (Ad35.CS), followed by boosting with RTS,S in an improved MPL- and QS21-based adjuvant formulation, AS01B, maintains antibody responses and dramatically increases levels of T cells producing gamma interferon and other Th1 cytokines in response to CS peptides. The increased T-cell responses induced by the combination of Ad35.CS and RTS,S/AS01B are sustained for at least 6 months postvaccination and may translate to improved and more durable protection against P. falciparum infection in humans.
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Affiliation(s)
- V Ann Stewart
- Division of Malaria Vaccine Development, Walter Reed Army Institute of Research, Silver Spring, MD, USA.
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37
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Stoute JA, Gombe J, Withers MR, Siangla J, McKinney D, Onyango M, Cummings JF, Milman J, Tucker K, Soisson L, Stewart VA, Lyon JA, Angov E, Leach A, Cohen J, Kester KE, Ockenhouse CF, Holland CA, Diggs CL, Wittes J, Heppner DG. Phase 1 randomized double-blind safety and immunogenicity trial of Plasmodium falciparum malaria merozoite surface protein FMP1 vaccine, adjuvanted with AS02A, in adults in western Kenya. Vaccine 2007; 25:176-84. [PMID: 16388879 DOI: 10.1016/j.vaccine.2005.11.037] [Citation(s) in RCA: 68] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/07/2005] [Revised: 10/29/2005] [Accepted: 11/18/2005] [Indexed: 11/22/2022]
Abstract
We report the first trial of candidate malaria vaccine antigen FMP1, a 42kDa fragment from the C-terminus of merozoite surface protein-1 (MSP-1) from the 3D7 strain of Plasmodium falciparum, in an endemic area. Forty adult male and female residents of western Kenya were enrolled to receive 3 doses of either FMP1/AS02A or Imovax rabies vaccine by intra-deltoid injection on a 0, 1, 2 month schedule. Thirty-seven volunteers received all three immunizations and 38 completed the 12-month evaluation period. Slightly more recipients of the FMP1/AS02A vaccine experienced any instance of pain at 24 h post-immunization than in the Imovax group (95% versus 65%), but otherwise the two vaccines were equally safe and well-tolerated. Baseline antibody levels were high in both groups and were boosted in the FMP1/AS02A group. Longitudinal models revealed a highly significant difference between groups for both the average post-baseline antibody responses to MSP-1(42) (F1,335=13.16; P<0.001) and the Day 90 responses to MSP-1(42) (F1,335=16.69; P<0.001). The FMP1/AS02A vaccine is safe and immunogenic in adults and should progress to safety testing in children at greatest risk of malaria.
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Affiliation(s)
- José A Stoute
- US Army Medical Research Unit and the Kenya Medical Research Institute, Nairobi, Kenya.
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38
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Ockenhouse CF, Hu WC, Kester KE, Cummings JF, Stewart A, Heppner DG, Jedlicka AE, Scott AL, Wolfe ND, Vahey M, Burke DS. Common and divergent immune response signaling pathways discovered in peripheral blood mononuclear cell gene expression patterns in presymptomatic and clinically apparent malaria. Infect Immun 2006; 74:5561-73. [PMID: 16988231 PMCID: PMC1594921 DOI: 10.1128/iai.00408-06] [Citation(s) in RCA: 102] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/05/2023] Open
Abstract
Using genome-wide expression profiles from persons either experimentally challenged with malaria-infected mosquitoes or naturally infected with Plasmodium falciparum malaria, we present details of the transcriptional changes that occur with infection and that either are commonly shared between subjects with presymptomatic and clinically apparent malaria or distinguish these two groups. Toll-like receptor signaling through NF-kappaB pathways was significantly upregulated in both groups, as were downstream genes that function in phagocytosis and inflammation, including the cytokines tumor necrosis factor alpha, gamma interferon (IFN-gamma), and interleukin-1beta (IL-1beta). The molecular program derived from these signatures illuminates the closely orchestrated interactions that regulate gene expression by transcription factors such as IRF-1 in the IFN-gamma signal transduction pathway. Modulation of transcripts in heat shock and glycolytic enzyme genes paralleled the intensity of infection. Major histocompatibility complex class I molecules and genes involved in class II antigen presentation are significantly induced in 90% of malaria-infected persons regardless of group. Differences between early presymptomatic infection and natural infection involved genes that regulate the induction of apoptosis through mitogen-activated protein (MAP) kinases and signaling pathways through the endogenous pyrogen IL-1beta, a major inducer of fever. The induction of apoptosis in peripheral blood mononuclear cells from patients with naturally acquired infection impacted the mitochondrial control of apoptosis and the activation of MAP kinase pathways centered around MAPK14 (p38alpha and p38beta). Our findings confirm and extend findings regarding aspects of the earliest responses to malaria infection at the molecular level, which may be informative in elucidating how innate and adaptive immune responses may be modulated in different stages of infection.
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Affiliation(s)
- Christian F Ockenhouse
- Division of Communicable Disease and Immunology, Walter Reed Army Institute of Research, Silver Spring, MD 20910.
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Withers MR, McKinney D, Ogutu BR, Waitumbi JN, Milman JB, Apollo OJ, Allen OG, Tucker K, Soisson LA, Diggs C, Leach A, Wittes J, Dubovsky F, Stewart VA, Remich SA, Cohen J, Ballou WR, Holland CA, Lyon JA, Angov E, Stoute JA, Martin SK, Heppner DG. Safety and reactogenicity of an MSP-1 malaria vaccine candidate: a randomized phase Ib dose-escalation trial in Kenyan children. PLoS Clin Trials 2006; 1:e32. [PMID: 17124529 PMCID: PMC1851726 DOI: 10.1371/journal.pctr.0010032] [Citation(s) in RCA: 48] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 05/16/2006] [Accepted: 09/20/2006] [Indexed: 11/19/2022]
Abstract
OBJECTIVE Our aim was to evaluate the safety, reactogenicity, and immunogenicity of an investigational malaria vaccine. DESIGN This was an age-stratified phase Ib, double-blind, randomized, controlled, dose-escalation trial. Children were recruited into one of three cohorts (dosage groups) and randomized in 2:1 fashion to receive either the test product or a comparator. SETTING The study was conducted in a rural population in Kombewa Division, western Kenya. PARTICIPANTS Subjects were 135 children, aged 12-47 mo. INTERVENTIONS Subjects received 10, 25, or 50 microg of falciparum malaria protein 1 (FMP1) formulated in 100, 250, and 500 microL, respectively, of AS02A, or they received a comparator (Imovax (rabies vaccine). OUTCOME MEASURES We performed safety and reactogenicity parameters and assessment of adverse events during solicited (7 d) and unsolicited (30 d) periods after each vaccination. Serious adverse events were monitored for 6 mo after the last vaccination. RESULTS Both vaccines were safe and well tolerated. FMP1/AS02A recipients experienced significantly more pain and injection-site swelling with a dose-effect relationship. Systemic reactogenicity was low at all dose levels. Hemoglobin levels remained stable and similar across arms. Baseline geometric mean titers were comparable in all groups. Anti-FMP1 antibody titers increased in a dose-dependent manner in subjects receiving FMP1/AS02A; no increase in anti-FMP1 titers occurred in subjects who received the comparator. By study end, subjects who received either 25 or 50 microg of FMP1 had similar antibody levels, which remained significantly higher than that of those who received the comparator or 10 microg of FMP1. A longitudinal mixed effects model showed a statistically significant effect of dosage level on immune response (F(3,1047) = 10.78, or F(3, 995) = 11.22, p < 0.001); however, the comparison of 25 microg and 50 microg recipients indicated no significant difference (F(1,1047) = 0.05; p = 0.82). CONCLUSIONS The FMP1/AS02A vaccine was safe and immunogenic in malaria-exposed 12- to 47-mo-old children and the magnitude of immune response of the 25 and 50 microg doses was superior to that of the 10 microg dose.
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Affiliation(s)
- Mark R Withers
- United States Army Medical Research Unit-Kenya, Nairobi, Kenya.
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Thera MA, Doumbo OK, Coulibaly D, Diallo DA, Sagara I, Dicko A, Diemert DJ, Heppner DG, Stewart VA, Angov E, Soisson L, Leach A, Tucker K, Lyke KE, Plowe CV. Safety and allele-specific immunogenicity of a malaria vaccine in Malian adults: results of a phase I randomized trial. PLoS Clin Trials 2006; 1:e34. [PMID: 17124530 PMCID: PMC1851722 DOI: 10.1371/journal.pctr.0010034] [Citation(s) in RCA: 55] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 03/28/2006] [Accepted: 10/10/2006] [Indexed: 11/18/2022]
Abstract
OBJECTIVES The objectives were to evaluate the safety, reactogenicity, and allele-specific immunogenicity of the blood-stage malaria vaccine FMP1/AS02A in adults exposed to seasonal malaria and the impact of natural infection on vaccine-induced antibody levels. DESIGN We conducted a randomized, double-blind, controlled phase I clinical trial. SETTING Bandiagara, Mali, West Africa, is a rural town with intense seasonal transmission of Plasmodium falciparum malaria. PARTICIPANTS Forty healthy, malaria-experienced Malian adults aged 18-55 y were enrolled. INTERVENTIONS The FMP1/AS02A malaria vaccine is a 42-kDa recombinant protein based on the carboxy-terminal end of merozoite surface protein-1 (MSP-1(42)) from the 3D7 clone of P. falciparum, adjuvanted with AS02A. The control vaccine was a killed rabies virus vaccine (Imovax). Participants were randomized to receive either FMP1/AS02A or rabies vaccine at 0, 1, and 2 mo and were followed for 1 y. OUTCOME MEASURES Solicited and unsolicited adverse events and allele-specific antibody responses to recombinant MSP-1(42) and its subunits derived from P. falciparum strains homologous and heterologous to the 3D7 vaccine strain were measured. RESULTS Transient local pain and swelling were more common in the malaria vaccine group than in the control group (11/20 versus 3/20 and 10/20 versus 6/20, respectively). MSP-1(42) antibody levels rose during the malaria transmission season in the control group, but were significantly higher in malaria vaccine recipients after the second immunization and remained higher after the third immunization relative both to baseline and to the control group. Immunization with the malaria vaccine was followed by significant increases in antibodies recognizing three diverse MSP-1(42) alleles and their subunits. CONCLUSIONS FMP1/AS02A was well tolerated and highly immunogenic in adults exposed to intense seasonal malaria transmission and elicited immune responses to genetically diverse parasite clones. Anti-MSP-1(42) antibody levels followed a seasonal pattern that was significantly augmented and prolonged by the malaria vaccine.
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Affiliation(s)
- Mahamadou A Thera
- Malaria Research and Training Center, University of Bamako, Bamako, Mali
| | - Ogobara K Doumbo
- Malaria Research and Training Center, University of Bamako, Bamako, Mali
| | - Drissa Coulibaly
- Malaria Research and Training Center, University of Bamako, Bamako, Mali
| | - Dapa A Diallo
- Malaria Research and Training Center, University of Bamako, Bamako, Mali
| | - Issaka Sagara
- Malaria Research and Training Center, University of Bamako, Bamako, Mali
| | - Alassane Dicko
- Malaria Research and Training Center, University of Bamako, Bamako, Mali
| | - David J Diemert
- Malaria Vaccine Development Branch, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Bethesda, Maryland, United States of America
| | - D. Gray Heppner
- Department of Immunology, Walter Reed Army Institute of Research, Silver Spring, Maryland, United States of America
| | - V. Ann Stewart
- Department of Immunology, Walter Reed Army Institute of Research, Silver Spring, Maryland, United States of America
| | - Evelina Angov
- Department of Immunology, Walter Reed Army Institute of Research, Silver Spring, Maryland, United States of America
| | - Lorraine Soisson
- United States Agency for International Development, Washington, D. C., United States of America
| | | | - Kathryn Tucker
- Statistics Collaborative, Washington, D. C., United States of America
| | - Kirsten E Lyke
- Center for Vaccine Development, University of Maryland School of Medicine, Baltimore, Maryland, United States of America
| | - Christopher V Plowe
- Center for Vaccine Development, University of Maryland School of Medicine, Baltimore, Maryland, United States of America
- * To whom correspondence should be addressed. E-mail:
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Brando C, Ware LA, Freyberger H, Kathcart A, Barbosa A, Cayphas S, Demoitie MA, Mettens P, Heppner DG, Lanar DE. Murine immune responses to liver-stage antigen 1 protein FMP011, a malaria vaccine candidate, delivered with adjuvant AS01B or AS02A. Infect Immun 2006; 75:838-45. [PMID: 17101665 PMCID: PMC1828476 DOI: 10.1128/iai.01075-06] [Citation(s) in RCA: 17] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Liver-stage antigen 1 (LSA1) is expressed by Plasmodium falciparum only during the intrahepatic cell stage of the parasite's development. Immunoepidemiological studies in regions where malaria is endemic suggested an association between the level of LSA1-specific humoral and cell-mediated immune responses and susceptibility to clinical malaria. A recombinant LSA1 protein, FMP011, has been manufactured as a preerythrocytic vaccine to induce an immune response that would have the effect of controlling parasitemia and disease in humans. To evaluate the immunogenicity of FMP011, we analyzed the immune response of three inbred strains of mice to antigen immunization using two different adjuvant formulations, AS01B and AS02A. We report here the ability of BALB/c and A/J mice, but not C57BL/6J mice, to mount FMP011-specific humoral (antibody titer) and cellular (gamma interferon [IFN-gamma] production) responses following immunization with FMP011 formulated in AS01B or AS02A. Immunization of BALB/c and A/J mice with FMP011/AS01B induced more antigen-specific IFN-gamma-producing splenocytes than immunization with FMP011/AS02A. A slightly higher titer of antibody was induced using AS02A than AS01B in both strains. C57BL/6J mice did not respond with any detectable FMP011-specific IFN-gamma splenocytes or antibody when immunized with FMP011 in AS01B or AS02A. Intracellular staining of cells isolated from FMP011/AS01B-immunized BALB/c mice indicated that CD4(+) cells, but not CD8(+) cells, were the main IFN-gamma-producing splenocyte. However, inclusion of blocking anti-CD4(+) antibody during the in vitro restimulation ELISpot analysis failed to completely abolish IFN-gamma production, indicating that while CD4(+) T cells were the major source of IFN-gamma, other cell types also were involved.
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Affiliation(s)
- Clara Brando
- Division of Malaria Vaccine Development, Walter Reed Army Institute of Research, Silver Spring, USA
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Stewart VA, McGrath SM, Walsh DS, Davis S, Hess AS, Ware LA, Kester KE, Cummings JF, Burge JR, Voss G, Delchambre M, Garçon N, Tang DB, Cohen JD, Heppner DG. Pre-clinical evaluation of new adjuvant formulations to improve the immunogenicity of the malaria vaccine RTS,S/AS02A. Vaccine 2006; 24:6483-92. [PMID: 16904798 DOI: 10.1016/j.vaccine.2006.06.033] [Citation(s) in RCA: 67] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/28/2006] [Revised: 06/02/2006] [Accepted: 06/14/2006] [Indexed: 10/24/2022]
Abstract
BACKGROUND RTS,S/AS02A, a pre-erythrocytic Plasmodium falciparum vaccine based upon the circumsporozoite protein, is the only vaccine demonstrated in field trials to confer partial protection against a range of malaria disease manifestations. Pre-clinical studies are on-going to identify new RTS,S formulations with improved magnitude and duration of specific immunity. METHODS Rhesus macaques were immunized with saline or one of four "RTS,S/adjuvant" formulations at 0, 4, and 12 weeks: RTS,S/AS01B, RTS,S/AS02A-standard (current formulation), RTS,S/AS05 or RTS,S/AS06. An RTS,S/AS02A-accelerated group was immunized at 0, 1, and 4 weeks. Outcomes were safety, RTS,S-specific antibody, and IFN-gamma and IL-5 ELISpots (weeks 14 and 34). FINDINGS All regimens were safe and, except for RTS,S/AS06, generated equivalent high titer antibody levels. For IFN-gamma ELISpots, RTS,S/AS01B had the highest geometric mean (GM) values at weeks 14 and 34, and was the only group with an overall GM mean (weeks 14+34) higher than RTS,S/AS02A-standard (p<0.015). For IFN-gamma to IL-5 ELISpot response ratios, RTS,S/AS01B had the highest values at weeks 14 and 34, and was the only group higher than RTS,S/AS02A-standard at each individual time point and overall (weeks 14+34) (p<0.015). INTERPRETATION RTS,S/AS01B is a safe and immunogenically superior formulation for cellular responses, in comparison with the RTS,S/AS02A-standard. Phase 1, 2a, and 2b clinical trials are underway to determine if RTS,S/AS01B demonstrates improved immunogenicity and protective efficacy against experimental challenge and natural mosquito-borne malaria.
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MESH Headings
- Adjuvants, Immunologic/administration & dosage
- Adjuvants, Immunologic/chemistry
- Adjuvants, Immunologic/pharmacology
- Animals
- Antibodies, Protozoan/analysis
- Antibodies, Protozoan/biosynthesis
- Antibody Specificity
- Blood Chemical Analysis
- Chemistry, Pharmaceutical
- Cytokines/biosynthesis
- Data Interpretation, Statistical
- Erythrocyte Count
- Immunity, Cellular/physiology
- Immunization, Secondary
- Interferon-gamma/pharmacology
- Interleukin-5/pharmacology
- Leukocyte Count
- Macaca mulatta
- Malaria Vaccines/administration & dosage
- Malaria Vaccines/adverse effects
- Malaria Vaccines/immunology
- Malaria, Falciparum/immunology
- Monocytes/immunology
- Plasmodium falciparum/immunology
- Quality Control
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Affiliation(s)
- V Ann Stewart
- Department of Immunology, Walter Reed Army Institute of Research, Silver Spring, Maryland 20910, USA.
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Stewart VA, Walsh DS, McGrath SM, Kester KE, Cummings JF, Voss G, Delchambre M, Garçon N, Cohen JD, Heppner DG. Cutaneous delayed-type hypersensitivity (DTH) in a multi-formulation comparator trial of the anti-falciparum malaria vaccine candidate RTS,S in rhesus macaques. Vaccine 2006; 24:6493-502. [PMID: 16911849 DOI: 10.1016/j.vaccine.2006.06.035] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/30/2006] [Revised: 06/02/2006] [Accepted: 06/14/2006] [Indexed: 11/27/2022]
Abstract
BACKGROUND Studies are underway to identify more immunogenic formulations of the existing anti-falciparum malaria vaccine RTS,S/AS02A. To supplement in vitro immunogenicity assays, cutaneous delayed-type hypersensitivity (DTH) may be a useful indicator of functional, cell-mediated immunogenicity. METHODS Adult rhesus monkeys were immunized with saline or one of four RTS,S/adjuvant formulations: RTS,S/AS01B, RTS,S/AS02A-standard (current formulation), RTS,S/AS05 or RTS,S/AS06 at 0, 4, and 12 weeks. An additional cohort received RTS,S/AS02A-accelerated, at 0, 1, and 4 weeks. Six months after completing immunizations, five vaccine-relevant antigens (high and low doses) and two controls were administered intradermally. DTH reactivity (induration) was measured at 48 and 72h, and selected sites were biopsied for histological confirmation. RESULTS In comparison with RTS,S/AS02A-standard, RTS,S/AS01B and RTS,S/AS05 each had larger mean reactions (induration) at 5 of 10 (p<0.01, at each site) and 1 of 10 (p<0.05, at the single site) vaccine relevant test sites, respectively. Histologically, perivascular mononuclear cell infiltrates, a cardinal feature of DTH, were largest in the RTS,S/AS01B monkeys. INTERPRETATION In DTH testing, with histological confirmation, RTS,S/AS01B was immunogenically superior to RTS,S/AS02A-standard and two other novel RTS,S formulations. The DTH outcomes paralleled conventional in vitro cellular immunogenicity assessments in distinguishing among similar RTS,S formulations, even at 6 months after final vaccination.
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Affiliation(s)
- V Ann Stewart
- Department of Immunology, Walter Reed Army Institute of Research, Silver Spring, MD 20910, USA.
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44
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Stoute JA, Heppner DG, Mason CJ, Siangla J, Opollo MO, Kester KE, Vigneron L, Voss G, Walter MJ, Tornieporth N, Cohen JD, Ballou WR. Phase 1 safety and immunogenicity trial of malaria vaccine RTS,S/AS02A in adults in a hyperendemic region of western Kenya. Am J Trop Med Hyg 2006; 75:166-70. [PMID: 16837726] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 05/10/2023] Open
Abstract
We conducted a phase 1 trial of candidate malaria vaccine RTS,S/AS02A in western Kenya to determine its safety and immunogenicity in healthy adults in an area hyperendemic for malaria. Twenty adults were enrolled and received RTS,S/AS02A (50 microg of RTS,S in 0.5 mL of AS02A) by intramuscular injection on a 0-, 28-, and 178-day schedule. All 60 scheduled immunizations were given, and 18 of 20 volunteers completed the last study visit on day 210. The vaccine was safe and well-tolerated. There were no vaccine-related severe adverse events. The most common solicited adverse events associated with immunization were injection site pain and headache. The geometric mean concentration of antibodies to circumsporozoite protein was 1.9 microg/mL at baseline and it increased 2-4 weeks after each dose to 16, 17.8, and 36.6 microg/mL, respectively. These safety and immunogenicity data from adults in hyperendemic Kenya are comparable to data reported earlier from two trials in west African adults in hypo-endemic and meso-endemic areas of The Gambia. We conclude that in this small study, RTS,S/AS02A is safe and similarly immunogenic in malaria-exposed African adults of different ethnicity in different transmission settings.
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Walsh DS, Gettayacamin M, Leitner WW, Lyon JA, Stewart VA, Marit G, Pichyangkul S, Gosi P, Tongtawe P, Kester KE, Holland CA, Kolodny N, Cohen J, Voss G, Ballou WR, Heppner DG. Heterologous prime-boost immunization in rhesus macaques by two, optimally spaced particle-mediated epidermal deliveries of Plasmodium falciparum circumsporozoite protein-encoding DNA, followed by intramuscular RTS,S/AS02A☆☆☆. Vaccine 2006; 24:4167-78. [PMID: 16574282 DOI: 10.1016/j.vaccine.2006.02.041] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/03/2005] [Revised: 01/25/2006] [Accepted: 02/06/2006] [Indexed: 11/17/2022]
Abstract
BACKGROUND RTS,S/AS02A, a recombinant Plasmodium falciparum vaccine based on the circumsporozoite protein (CSP) repeat and C-terminus regions, elicits strong humoral and Th1 cell-mediated immunity. In field studies, RTS,S/AS02A reduced malaria infection, clinical episodes, and disease severity. Heterologous prime-boost immunization regimens, optimally spaced, might improve the protective immunity of RTS,S/AS02A. METHODS DNA plasmid encoding P. falciparum CSP (3D7) was administered to six experimental groups of rhesus monkeys (N = 5) by gene gun (coded as D), followed by a 1/5th human dose of RTS,S/AS02A (coded as R). Immunization regimens, including a numeral to denote weeks between immunizations, were D-4-R, D-16-R, D-4-D-4-R, D-4-D-16-R, D-16-D-4-R and D-16-D-16-R. A control group (N = 5) received a single 1/5th dose of RTS,S/AS02A. Endpoints were antibody (Ab) to homologous CSP repeat and C-terminus regions and delayed-type hypersensitivity (DTH) to CSP peptides. FINDINGS Monkeys immunized twice with DNA, 16 weeks apart (D-16-D-4-R and D-16-D-16-R), developed higher levels of anti-C-terminus Abs than control monkeys (p<0.02). No CSP DNA priming regimen increased RTS,S/AS02A-induced Ab to CSP repeats. At 16 months after first immunization, D-R and D-D-R, but not control, monkeys had histologically confirmed DTH reactions against CSP C-terminus, which persisted at repeat testing 12 months later. INTERPRETATION Two optimally spaced, particle-mediated epidermal deliveries of CSP DNA improved the humoral immunogenicity of a single dose of RTS,S/AS02A. Further, CSP DNA prime followed by one dose of RTS,S/AS02A gave biopsy proven DTH reactions against CSP C-terminus of up to 2 years duration, implying the induction of CD4+ memory T cells. Heterologous prime-boost strategies for malaria involving gene gun delivered DNA or more potent vectors, administered at optimal intervals, warrant further investigation.
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Affiliation(s)
- Douglas S Walsh
- Department of Immunology & Medicine, US Army Medical Component, Armed Forces Research Institute of Medical Sciences (AFRIMS), Bangkok, Thailand.
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Ockenhouse CF, Angov E, Kester KE, Diggs C, Soisson L, Cummings JF, Stewart AV, Palmer DR, Mahajan B, Krzych U, Tornieporth N, Delchambre M, Vanhandenhove M, Ofori-Anyinam O, Cohen J, Lyon JA, Heppner DG. Phase I safety and immunogenicity trial of FMP1/AS02A, a Plasmodium falciparum MSP-1 asexual blood stage vaccine☆. Vaccine 2006; 24:3009-17. [PMID: 16356603 DOI: 10.1016/j.vaccine.2005.11.028] [Citation(s) in RCA: 76] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/12/2005] [Revised: 10/26/2005] [Accepted: 11/01/2005] [Indexed: 11/21/2022]
Abstract
We report the first safety and immunogenicity trial of the Plasmodium falciparum malaria blood stage vaccine candidate, FMP1/AS02A consisting of the FMP1 antigen, an Escherichia coli-expressed His-tagged fusion protein from the 42 kDa C-terminal fragment from the 3D7 clone of the merozoite surface protein 1 formulated in the AS02A adjuvant. An open label, prospective, single-center Phase I dose escalation trial of FMP1/AS02A was conducted in 15 adult malaria-naïve human volunteers to assess safety, reactogenicity, and immunogenicity. The vaccine was safe and well-tolerated and no serious adverse events were observed. The vaccine induced high-titer ELISA and IFA responses in all volunteers. Proliferative and ELISPOT responses were induced to vaccine antigen. Biologically active antibodies were induced as measured by GIA. This study establishes the foundation to further evaluate and measure the vaccine's ability to reduce morbidity and mortality in target populations directly affected by P. falciparum malaria.
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MESH Headings
- Adjuvants, Immunologic/administration & dosage
- Adjuvants, Immunologic/pharmacology
- Adolescent
- Adult
- Animals
- Antibodies, Protozoan/blood
- Drug Combinations
- Enzyme-Linked Immunosorbent Assay
- Female
- Fluorescent Antibody Technique, Indirect
- Humans
- Interferon-gamma/biosynthesis
- L-Lactate Dehydrogenase/analysis
- Lipid A/administration & dosage
- Lipid A/analogs & derivatives
- Lipid A/pharmacology
- Malaria Vaccines/administration & dosage
- Malaria Vaccines/adverse effects
- Malaria Vaccines/immunology
- Male
- Merozoite Surface Protein 1/immunology
- Middle Aged
- Plasmodium falciparum/growth & development
- Plasmodium falciparum/immunology
- Saponins/administration & dosage
- Saponins/pharmacology
- T-Lymphocytes/immunology
- Vaccines, Subunit/administration & dosage
- Vaccines, Subunit/adverse effects
- Vaccines, Subunit/immunology
- Vaccines, Synthetic/administration & dosage
- Vaccines, Synthetic/adverse effects
- Vaccines, Synthetic/immunology
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Affiliation(s)
- Christian F Ockenhouse
- Department of Immunology, Walter Reed Army Institute of Research, Silver Spring, MD 20910, USA.
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Dunachie SJ, Walther M, Vuola JM, Webster DP, Keating SM, Berthoud T, Andrews L, Bejon P, Poulton I, Butcher G, Watkins K, Sinden RE, Leach A, Moris P, Tornieporth N, Schneider J, Dubovsky F, Tierney E, Williams J, Heppner DG, Gilbert SC, Cohen J, Hill AVS. A clinical trial of prime-boost immunisation with the candidate malaria vaccines RTS,S/AS02A and MVA-CS. Vaccine 2006; 24:2850-9. [PMID: 16434127 DOI: 10.1016/j.vaccine.2005.12.041] [Citation(s) in RCA: 75] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/04/2005] [Revised: 12/16/2005] [Accepted: 12/22/2005] [Indexed: 11/21/2022]
Abstract
Heterologous prime-boost immunisation with RTS,S/AS02A and the poxvirus MVA-CS was evaluated in 18 healthy malaria-naïve subjects in Oxford. Both priming with RTS,S and boosting MVA-CS, and the reverse, were found to be safe and well tolerated. T cell responses as measured by IFN-gamma ex vivo ELISPOT were induced, but the responses were low to moderate in both groups, with heterologous boosting yielding only small increments in T cell immunogenicity and no increased antibody response. Protection against 3D7 Plasmodium falciparum sporozoite challenge 4 weeks after the final vaccination was equal for both regimens at 33% (95% C.I. 4.3-77.7%), with one subject remaining fully protected on rechallenge at 5 months.
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Affiliation(s)
- Susanna J Dunachie
- Centre for Clinical Vaccinology and Tropical Medicine, Nuffield Department of Medicine, University of Oxford, Churchill Hospital, Oxford OX3 7LJ, UK.
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Heppner DG, Walsh DS, Uthaimongkol N, Tang DB, Tulyayon S, Permpanich B, Wimonwattrawatee T, Chuanak N, Laoboonchai A, Sookto P, Brewer TG, McDaniel P, Eamsila C, Yongvanitchit K, Uhl K, Kyle DE, Keep LW, Miller RE, Wongsrichanalai C. Randomized, controlled, double-blind trial of daily oral azithromycin in adults for the prophylaxis of Plasmodium vivax malaria in Western Thailand. Am J Trop Med Hyg 2005; 73:842-9. [PMID: 16282291] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 05/05/2023] Open
Abstract
We assessed the prophylactic efficacy of azithromycin (250 mg/day) against malaria in 276 adults in western Thailand in a randomized, double-blind, placebo-controlled trial. After antimalarial suppressive treatment, volunteers were randomized in a 2:1 ratio to either the azithromycin or placebo, respectively. Study medication was given for an average of 74 days. The azithromycin group (n = 179) had five endpoint parasitemias (1 Plasmodium vivax and 4 P. falciparum), and the placebo group (n = 97) had 28 endpoint parasitemias (21 P. vivax, 5 P. falciparum, and 2 mixed infections). Adverse events and compliance and withdrawal rates were similar in both groups. The protective efficacy (PE) of azithromycin was 98% for P. vivax (95% confidence interval [CI] = 88-100%). There were too few cases to reliably estimate the efficacy of azithromycin for P. falciparum (PE =71%, 95% C =-14-94%). We conclude that daily azithromycin was safe, well-tolerated, and had a high efficacy for the prevention of P. vivax malaria.
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Affiliation(s)
- D Gray Heppner
- Department of Immunology and Medicine, United States Army Medical Component, Armed Forces Research Institute of Medical Sciences, Bangkok, Thailand.
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Bojang KA, Olodude F, Pinder M, Ofori-Anyinam O, Vigneron L, Fitzpatrick S, Njie F, Kassanga A, Leach A, Milman J, Rabinovich R, McAdam KPWJ, Kester KE, Heppner DG, Cohen JD, Tornieporth N, Milligan PJM. Safety and immunogenicty of RTS,S/AS02A candidate malaria vaccine in Gambian children. Vaccine 2005; 23:4148-57. [PMID: 15964483 DOI: 10.1016/j.vaccine.2005.03.019] [Citation(s) in RCA: 71] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/17/2004] [Accepted: 03/09/2005] [Indexed: 11/28/2022]
Abstract
RTS,S/AS02A is a pre-erythrocytic malaria vaccine candidate in which a portion of the circumsporozoite surface protein (CSP) of Plasmodium falciparum is genetically linked to hepatitis B surface antigen (HBsAg) coexpressed in yeast with unfused HBsAg. The resulting particulate antigen is formulated with the adjuvant system AS02A. We have initiated the paediatric clinical development of this vaccine by conducting two sequential Phase I studies in children: a study in older children (6--11 years), followed by a second study in younger children (1--5 years). In each study, a double-blind, randomised controlled, staggered, dose-escalation design was used to evaluate 10 microg RTS,S dose (10 microg RTS,S in 0.1mL AS02A), 25 microg dose (25 microg RTS,S in 0.25mL AS02A) and finally a 50 microg dose (50 microg RTS,S in 0.5mL AS02A) of the RTS,S/AS02A candidate malaria vaccine administered according to a 0-, 1- and 3-month vaccination schedule. Safety and reactogenicity were evaluated before moving to a higher dose level. The RTS,S/AS02A vaccine was safe at all dose levels, in both age groups. No serious adverse events related to vaccination were reported. The frequency of local Grade 3 symptoms was low but tended to increase with increasing dose level. Grade 3 general adverse events in the RTS,S/AS02A groups were infrequent and of short duration. The majority of local and general Grade 3 symptoms resolved or decreased in intensity within 48h. The pattern and intensity of reactogenicity seen in these studies are similar to those of previous studies with RTS,S/AS02A. All doses were highly immunogenic for anti-CSP and anti-HBsAg antibodies. The pooled anti-CSP antibody data from the two studies showed that the 25 microg dose and 50 microg dose anti-CSP antibody response were similar at both dose levels. However, the immunogenicity of the 10 microg dose anti-CSP response was significantly lower than that of either the 50 microg or 25 microg dose. The 25 microg dose was selected for future studies of RTS,S/AS02A in paediatric populations.
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Affiliation(s)
- Kalifa A Bojang
- Medical Research Council Laboratories, P.O. Box 273, Banjul, The Gambia.
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50
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Yoon IK, Angov E, Larson D, Heppner DG, Cummings JF, Stewart VA. Characterization of a human reference standard for antibody to Plasmodium falciparum merozoite surface protein 1(42). Am J Trop Med Hyg 2005; 72:714-8. [PMID: 15964955] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 05/03/2023] Open
Abstract
Volunteers vaccinated with a candidate malaria vaccine containing merozoite surface protein 1(42) (MSP-1(42)) exhibit antibodies to MSP-1(42) that are measured by enzyme-linked immunosorbent assay (ELISA). The purpose of this study was to make a human reference standard for MSP-1(42) antibody measured in absolute quantity units using pooled plasma samples known to contain high titers of MSP-1(42) antibody based on previous ELISA results. Immobilized metal affinity chromatography was used to determine the amount of MSP-1(42) antibody in this plasma pool. Hexahistidine-tagged MSP-1(42) antigen adsorbed to nickel-chelating resin was used to capture MSP-1(42) antibody from the plasma pool. The intact MSP-1(42) antibody-antigen complexes were eluted and total IgG was measured by an ELISA standardized against purified human IgG. In this way, the human reference standard was determined to contain 48.3 microg/mL of MSP-1(42) antibody. This reference standard may be useful as a quantitative working standard for measuring MSP-1(42) antibody response in future vaccine clinical trials involving MSP-1.
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Affiliation(s)
- In-Kyu Yoon
- Division of Communicable Diseases and Immunology, Department of Immunology, Walter Reed Army Institute of Research, Silver Spring, Maryland 20910, USA.
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