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Syntin P, Piras-Douce F, Dalençon F, Garinot M, Haensler J. Nonclinical safety assessments of a novel synthetic toll-like receptor 4 agonist and saponin based adjuvant. Toxicol Appl Pharmacol 2023; 460:116358. [PMID: 36572229 DOI: 10.1016/j.taap.2022.116358] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/03/2022] [Revised: 12/16/2022] [Accepted: 12/18/2022] [Indexed: 12/24/2022]
Abstract
A full nonclinical safety package was performed to support the clinical use of SPA14, a novel liposome-based vaccine adjuvant containing the synthetic toll-like receptor 4 agonist E6020 and saponin QS21. E6020 and QS21 were tested negative for their potential genotoxic effects in Ames, micronucleus, or mouse-lymphoma TK (thymidine kinase) assay. To evaluate the potential local and systemic effects of SPA14, two toxicity studies were performed in rabbits. In the first dose range finding toxicity study, rabbits received two intramuscular injections of SPA14 at increasing doses of E6020 combined with two antigens, a control (saline), the two antigens alone, or the antigens adjuvanted with a liposome-based adjuvant AS01B. No systemic toxicity was detected, supporting the dose of 5 μg of E6020 for the subsequent pivotal study. In the second repeated dose toxicity study, rabbits received four intramuscular injections of SPA14 alone, a control (saline), SPA14 combined with two antigens, the two antigens alone, or the antigens combined with AF03 adjuvant, which is a squalene-based emulsion. SPA14 alone or in combination with the antigens was well tolerated and did not cause any systemic toxicity. Finally, two safety pharmacology studies were conducted to assess potential cardiovascular and respiratory effects of E6020 and SPA14 in conscious telemetered cynomolgus monkeys and beagle dogs, respectively. One subcutaneous injection of E6020 in monkeys and one intramuscular injection of SPA14 in dogs had no consequences on respiratory and cardiovascular functions. Altogether these results support the clinical development of SPA14.
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Rao VV, Godin CS, Lacy MJ, Inglefield JR, Park S, Blauth B, Reece JJ, Ionin B, Savransky V. Evaluation of the AV7909 Anthrax Vaccine Toxicity in Sprague Dawley Rats Following Three Intramuscular Administrations. Int J Toxicol 2021; 40:442-452. [PMID: 34281421 PMCID: PMC8532110 DOI: 10.1177/10915818211031239] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
Abstract
AV7909 is a next-generation anthrax vaccine under development for post-exposure prophylaxis following suspected or confirmed Bacillus anthracis exposure, when administered in conjunction with the recommended antibacterial regimen. AV7909 consists of the FDA-approved BioThrax® vaccine (anthrax vaccine adsorbed) and an immunostimulatory Toll-like receptor 9 agonist oligodeoxynucleotide adjuvant, CPG 7909. The purpose of this study was to evaluate the potential systemic and local toxicity of AV7909 when administered via repeat intramuscular injection to the right thigh muscle (biceps femoris) to male and female Sprague Dawley rats. The vaccine was administered on Days 1, 15, and 29 and the animals were assessed for treatment-related effects followed by a 2-week recovery period to evaluate the persistence or reversibility of any toxic effects. The AV7909 vaccine produced no apparent systemic toxicity based on evaluation of clinical observations, body weights, body temperature, clinical pathology, and anatomic pathology. Necrosis and inflammation were observed at the injection sites as well as in regional lymph nodes and adjacent tissues and were consistent with immune stimulation. Antibodies against B. anthracis protective antigen (PA) were detected in rats treated with the AV7909 vaccine, confirming relevance of this animal model for the assessment of systemic toxicity of AV7909. In contrast, sera of rats that received saline or soluble CPG 7909 alone were negative for anti-PA antibodies. Overall, 3 intramuscular immunizations of Sprague Dawley rats with AV7909 were well tolerated, did not induce mortality or any systemic adverse effects, and did not result in any delayed toxicity.
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Affiliation(s)
| | | | | | - Jon R. Inglefield
- Frederick National Laboratory for Cancer Research, Frederick, MD (current affiliation; JRI was affiliated with the Emergent BioSolutions Inc, Gaithersburg, MD at the time of the work)
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Stokes A, Pion J, Binazon O, Laffont B, Bigras M, Dubois G, Blouin K, Young JK, Ringenberg MA, Ben Abdeljelil N, Haruna J, Rodriguez LA. Nonclinical safety assessment of repeated administration and biodistribution of a novel rabies self-amplifying mRNA vaccine in rats. Regul Toxicol Pharmacol 2020; 113:104648. [PMID: 32240713 DOI: 10.1016/j.yrtph.2020.104648] [Citation(s) in RCA: 34] [Impact Index Per Article: 8.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/26/2019] [Revised: 03/09/2020] [Accepted: 03/23/2020] [Indexed: 11/25/2022]
Abstract
The novel self-amplifying mRNA (SAM) technology for vaccines consists of an engineered replication-deficient alphavirus genome encoding an RNA-dependent RNA polymerase and the gene of the target antigen. To validate the concept, the rabies glycoprotein G was chosen as antigen. The delivery system for this vaccine was a cationic nanoemulsion. To characterize the local tolerance, potential systemic toxicity and biodistribution of this vaccine, two nonclinical studies were performed. In the repeated dose toxicity study, the SAM vaccine was administered intramuscularly to rats on four occasions at two-week intervals followed by a four-week recovery period. SAM-related changes consisted of a transient increase in neutrophil count, alpha-2-macroglobulin and fibrinogen levels. Transient aspartate aminotransferase and alanine aminotransferase increases were also noted in females only. At necropsy, observations related to the elicited inflammatory reaction, such as enlargement of the draining lymph nodes were observed that were almost fully reversible by the end of the recovery period. In the biodistribution study, rats received a single intramuscular injection of SAM vaccine and then were followed until Day 60. Rabies RNA was found at the injection sites and in the draining lymph nodes one day after administration, then generally decreased in these tissues but remained detectable up to Day 60. Rabies RNA was also transiently found in blood, lungs, spleen and liver. No microscopic changes in the brain and spinal cord were recorded. In conclusion, these results showed that the rabies SAM vaccine was well-tolerated by the animals and supported the clinical development program.
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Affiliation(s)
| | - Johanne Pion
- Citoxlab (A Charles River Company), Laval (Québec), Canada
| | | | - Benoit Laffont
- Citoxlab (A Charles River Company), Laval (Québec), Canada
| | - Maude Bigras
- Citoxlab (A Charles River Company), Laval (Québec), Canada
| | | | - Karine Blouin
- Citoxlab (A Charles River Company), Laval (Québec), Canada
| | | | | | | | - Julius Haruna
- Citoxlab (A Charles River Company), Laval (Québec), Canada
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4
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Destexhe É, Grosdidier É, Bouhraoua A, Thirion-Delalande C, Bouzya B, Rouxel RN, Mallett CP, Baumeister J. Chimeric hemagglutinin supra-seasonal universal influenza vaccine candidates administered sequentially by the intramuscular route are locally and systemically well-tolerated in rabbits. Regul Toxicol Pharmacol 2020; 113:104625. [PMID: 32119974 DOI: 10.1016/j.yrtph.2020.104625] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/23/2019] [Revised: 01/24/2020] [Accepted: 02/25/2020] [Indexed: 11/28/2022]
Abstract
Sequential intramuscular immunization with chimeric hemagglutinins (cHA) composed of the same conserved HA stalk domain and distinct HA heads is a proposed strategy to produce a supra-seasonal universal influenza vaccine. To evaluate the local tolerance and the local and systemic effects of this strategy, two studies were performed in rabbits. In the first study, two different split virion monovalent cHA vaccines, containing cH5/1N1 and cH8/1N1, with or without AS01 or AS03, were injected at a two-week interval. In the second study, animals were given these vaccines and two weeks later an additional dose of split virion monovalent cHA vaccine containing cH11/1N1, with or without AS01 or AS03. General health status, rectal temperature, local tolerance, ophthalmology, hematology, coagulation, and blood chemistry parameters were monitored. Macroscopic and microscopic evaluations were performed three days after the last dose and after a treatment-free recovery period. The treatment-related changes included body weight loss and food consumption decrease, increases in neutrophil count, C-reactive protein and fibrinogen levels. Microscopic signs of inflammation at the injection sites and immune stimulation of the draining lymph nodes and spleen were also noticed. Most post-injection findings could be linked to the transient inflammation due to the establishment of the desired vaccine-elicited immune response, and were mainly observed in the adjuvanted groups. In conclusion, the sequential administration of different cHA vaccines was locally and systemically well-tolerated in rabbits.
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Guerra Mendoza Y, Garric E, Leach A, Lievens M, Ofori-Anyinam O, Pirçon JY, Stegmann JU, Vandoolaeghe P, Otieno L, Otieno W, Owusu-Agyei S, Sacarlal J, Masoud NS, Sorgho H, Tanner M, Tinto H, Valea I, Mtoro AT, Njuguna P, Oneko M, Otieno GA, Otieno K, Gesase S, Hamel MJ, Hoffman I, Kaali S, Kamthunzi P, Kremsner P, Lanaspa M, Lell B, Lusingu J, Malabeja A, Aide P, Akoo P, Ansong D, Asante KP, Berkley JA, Adjei S, Agbenyega T, Agnandji ST, Schuerman L. Safety profile of the RTS,S/AS01 malaria vaccine in infants and children: additional data from a phase III randomized controlled trial in sub-Saharan Africa. Hum Vaccin Immunother 2019; 15:2386-2398. [PMID: 31012786 PMCID: PMC6816384 DOI: 10.1080/21645515.2019.1586040] [Citation(s) in RCA: 22] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
A phase III, double-blind, randomized, controlled trial (NCT00866619) in sub-Saharan Africa showed RTS,S/AS01 vaccine efficacy against malaria. We now present in-depth safety results from this study. 8922 children (enrolled at 5–17 months) and 6537 infants (enrolled at 6–12 weeks) were 1:1:1-randomized to receive 4 doses of RTS,S/AS01 (R3R) or non-malaria control vaccine (C3C), or 3 RTS,S/AS01 doses plus control (R3C). Aggregate safety data were reviewed by a multi-functional team. Severe malaria with Blantyre Coma Score ≤2 (cerebral malaria [CM]) and gender-specific mortality were assessed post-hoc. Serious adverse event (SAE) and fatal SAE incidences throughout the study were 24.2%–28.4% and 1.5%–2.5%, respectively across groups; 0.0%–0.3% of participants reported vaccination-related SAEs. The incidence of febrile convulsions in children was higher during the first 2–3 days post-vaccination with RTS,S/AS01 than with control vaccine, consistent with the time window of post-vaccination febrile reactions in this study (mostly the day after vaccination). A statistically significant numerical imbalance was observed for meningitis cases in children (R3R: 11, R3C: 10, C3C: 1) but not in infants. CM cases were more frequent in RTS,S/AS01-vaccinated children (R3R: 19, R3C: 24, C3C: 10) but not in infants. All-cause mortality was higher in RTS,S/AS01-vaccinated versus control girls (2.4% vs 1.3%, all ages) in our setting with low overall mortality. The observed meningitis and CM signals are considered likely chance findings, that – given their severity – warrant further evaluation in phase IV studies and WHO-led pilot implementation programs to establish the RTS,S/AS01 benefit-risk profile in real-life settings.
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Affiliation(s)
| | | | | | | | | | | | | | | | | | | | - Seth Owusu-Agyei
- Kintampo Health Research Center , Kintampo , Ghana.,Diseases Control Department, London School of Hygiene and Tropical Medicine , London , UK
| | - Jahit Sacarlal
- Centro de Investigação em Saúde de Manhiça , Manhiça , Mozambique.,Faculdade de Medicina, Universidade Eduardo Mondlane (UEM) , Maputo , Mozambique
| | - Nahya Salim Masoud
- Muhimbili University of Health and Allied Sciences (MUHAS), Dar es Salaam and Ifakara Health Institute , Bagamoyo , Tanzania
| | - Hermann Sorgho
- Institut de Recherche en Science de la Santé , Nanoro , Burkina Faso
| | - Marcel Tanner
- Muhimbili University of Health and Allied Sciences (MUHAS), Dar es Salaam and Ifakara Health Institute , Bagamoyo , Tanzania.,Swiss Tropical and Public Health Institute , Basel , Switzerland.,Epidemiology and Medical Parasitology department, University of Basel , Basel , Switzerland
| | - Halidou Tinto
- Institut de Recherche en Science de la Santé , Nanoro , Burkina Faso
| | - Innocent Valea
- Institut de Recherche en Science de la Santé , Nanoro , Burkina Faso
| | - Ali Takadir Mtoro
- Muhimbili University of Health and Allied Sciences (MUHAS), Dar es Salaam and Ifakara Health Institute , Bagamoyo , Tanzania
| | - Patricia Njuguna
- Kenya Medical Research Institute-Wellcome Trust Research Programme, Centre for Geographic Medicine Research , Kilifi , Kenya.,Pwani University , Kilifi , Kenya.,University of Oxford , Oxford , UK
| | - Martina Oneko
- Kenya Medical Research Institute, Centre for Global Health Research , Kisumu , Kenya
| | | | - Kephas Otieno
- Kenya Medical Research Institute, Centre for Global Health Research , Kisumu , Kenya
| | - Samwel Gesase
- National Institute for Medical Research , Korogwe , Tanzania
| | - Mary J Hamel
- Division of Parasitic Diseases and Malaria, Center for Global Health, Centers for Disease Control and Prevention , Atlanta , GA , USA
| | - Irving Hoffman
- University of North Carolina Project , Lilongwe , Malawi
| | - Seyram Kaali
- Kintampo Health Research Center , Kintampo , Ghana
| | | | - Peter Kremsner
- Centre de Recherches Médicales de Lambaréné, Lambaréné, Gabon and Institute of Tropical Medicine, University of Tübingen , Tübingen , Germany
| | - Miguel Lanaspa
- Centro de Investigação em Saúde de Manhiça , Manhiça , Mozambique.,Barcelona Institute for Global Health (ISGlobal), Hospital Clínic-Universitat de Barcelona , Barcelona , Spain
| | - Bertrand Lell
- Centre de Recherches Médicales de Lambaréné, Lambaréné, Gabon and Institute of Tropical Medicine, University of Tübingen , Tübingen , Germany
| | - John Lusingu
- National Institute for Medical Research , Korogwe , Tanzania
| | | | - Pedro Aide
- Centro de Investigação em Saúde de Manhiça , Manhiça , Mozambique.,National Institute of Health, Ministry of Health , Maputo , Mozambique
| | - Pauline Akoo
- Kenya Medical Research Institute-Wellcome Trust Research Programme, Centre for Geographic Medicine Research , Kilifi , Kenya
| | - Daniel Ansong
- Kwame Nkrumah University of Science and Technology , Kumasi , Ghana
| | | | - James A Berkley
- Kenya Medical Research Institute-Wellcome Trust Research Programme, Centre for Geographic Medicine Research , Kilifi , Kenya.,University of Oxford , Oxford , UK
| | - Samuel Adjei
- Kwame Nkrumah University of Science and Technology , Kumasi , Ghana
| | - Tsiri Agbenyega
- Kwame Nkrumah University of Science and Technology , Kumasi , Ghana
| | - Selidji Todagbe Agnandji
- Centre de Recherches Médicales de Lambaréné, Lambaréné, Gabon and Institute of Tropical Medicine, University of Tübingen , Tübingen , Germany
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Investigating toxicity specific to adjuvanted vaccines. Regul Toxicol Pharmacol 2017; 91:29-38. [PMID: 28888957 DOI: 10.1016/j.yrtph.2017.09.003] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/07/2017] [Revised: 08/14/2017] [Accepted: 09/05/2017] [Indexed: 11/22/2022]
Abstract
In an attempt to understand the unique toxicity of adjuvanted vaccines, we studied how toxicity develops over time following vaccine administration. In addition to on- and off-target toxicity typically observed with general pharmaceuticals, we observed toxicity associated with both the generation and the broad action of effectors (antibodies and/or cytotoxic T lymphocytes, CTLs). The impact on effector generation appears to be related to local tolerance specific to the adjuvant. The vaccine immune response by effectors serves to demonstrate species relevance as outlined in the recent WHO guideline on the nonclinical evaluation of adjuvanted vaccines. When regarded as pharmaceuticals that function at sites of local administration, adjuvants have inherent on- and off-target toxicity. On-target toxicity of the adjuvant is typically associated with effector generation, and could vary depending on animal species. Therefore, the use of species with sensitivity to adjuvants described in the WHO guidelines is required to evaluate the toxicity of the vaccine associated with effector generation. Changes in safety pharmacology endpoints would be considered off-target and further studies are conducted only if changes in these endpoints are observed in nonclinical or clinical studies. Thus our decision tree does not recommend the routine conduct of stand-alone safety pharmacology studies.
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7
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Giordano G, Segal L, Prinsen M, Wijnands MVW, Garçon N, Destexhe E. Non-clinical safety assessment of single and repeated administration of gE/AS01 zoster vaccine in rabbits. J Appl Toxicol 2016; 37:132-141. [DOI: 10.1002/jat.3329] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/19/2015] [Revised: 02/19/2016] [Accepted: 03/09/2016] [Indexed: 11/06/2022]
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8
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Baldrick P. Dose site reactions and related findings after vaccine administration in safety studies. J Appl Toxicol 2016; 36:980-90. [DOI: 10.1002/jat.3314] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/29/2015] [Revised: 01/26/2016] [Accepted: 01/26/2016] [Indexed: 12/22/2022]
Affiliation(s)
- Paul Baldrick
- Regulatory Strategy; Covance Laboratories Ltd; England UK
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9
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RTS,S: Toward a first landmark on the Malaria Vaccine Technology Roadmap. Vaccine 2015; 33:7425-32. [PMID: 26431982 DOI: 10.1016/j.vaccine.2015.09.061] [Citation(s) in RCA: 61] [Impact Index Per Article: 6.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/28/2015] [Revised: 09/08/2015] [Accepted: 09/15/2015] [Indexed: 01/07/2023]
Abstract
The Malaria Vaccine Technology Roadmap calls for a 2015 landmark goal of a first-generation malaria vaccine that has protective efficacy against severe disease and death, lasting longer than one year. This review focuses on product development efforts over the last five years of RTS,S, a pre-erythrocytic, recombinant subunit, adjuvanted, candidate malaria vaccine designed with this goal of a first-generation malaria vaccine in mind. RTS,S recently completed a successful pivotal Phase III safety, efficacy and immunogenicity study. Although vaccine efficacy was found to be modest, a substantial number of cases of clinical malaria were averted over a 3-4 years period, particularly in settings of significant disease burden. European regulators have subsequently adopted a positive opinion under the Article 58 procedure for an indication of active immunization of children aged 6 weeks up to 17 months against malaria caused by Plasmodium falciparum and against hepatitis B. Further evaluations of the benefit, risk, feasibility and cost-effectiveness of RTS,S are now anticipated through policy and financing reviews at the global and national levels.
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Hu J, Qiu L, Wang X, Zou X, Lu M, Yin J. Carbohydrate-based vaccine adjuvants - discovery and development. Expert Opin Drug Discov 2015; 10:1133-44. [PMID: 26372693 DOI: 10.1517/17460441.2015.1067198] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/21/2023]
Abstract
INTRODUCTION The addition of a suitable adjuvant to a vaccine can generate significant effective adaptive immune responses. There is an urgent need for the development of novel po7tent and safe adjuvants for human vaccines. Carbohydrate molecules are promising adjuvants for human vaccines due to their high biocompatibility and good tolerability in vivo. AREAS COVERED The present review covers a few promising carbohydrate-based adjuvants, lipopolysaccharide, trehalose-6,6'-dibehenate, QS-21 and inulin as examples, which have been extensively studied in human vaccines in a number of preclinical and clinical studies. The authors discuss the current status, applications and strategies of development of each adjuvant and different adjuvant formulation systems. This information gives insight regarding the exciting prospect in the field of carbohydrate-based adjuvant research. EXPERT OPINION Carbohydrate-based adjuvants are promising candidates as an alternative to the Alum salts for human vaccines development. Furthermore, combining two or more adjuvants in one formulation is one of the effective strategies in adjuvant development. However, further research efforts are needed to study and develop novel adjuvants systems, which can be more stable, potent and safe. The development of synthetic carbohydrate chemistry can improve the study of carbohydrate-based adjuvants.
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Affiliation(s)
- Jing Hu
- a 1 Jiangnan University, Wuxi Medical School , Lihu Avenue 1800, 214122, Wuxi, China
| | - Liying Qiu
- a 1 Jiangnan University, Wuxi Medical School , Lihu Avenue 1800, 214122, Wuxi, China
| | - Xiaoli Wang
- b 2 Jiangnan University, The Key Laboratory of Carbohydrate Chemistry and Biotechnology, Ministry of Education, School of Biotechnology , Lihu Avenue 1800, 214122, Wuxi, China +86 51 085 328 229 ; +86 51 085 328 229 ;
| | - Xiaopeng Zou
- b 2 Jiangnan University, The Key Laboratory of Carbohydrate Chemistry and Biotechnology, Ministry of Education, School of Biotechnology , Lihu Avenue 1800, 214122, Wuxi, China +86 51 085 328 229 ; +86 51 085 328 229 ;
| | - Mengji Lu
- c 3 University Hospital Essen, Institute of Virology , Hufelandstr, 55, 45122 Essen, Germany +49 2 017 233 530 ; +49 2 017 235 929 ;
| | - Jian Yin
- b 2 Jiangnan University, The Key Laboratory of Carbohydrate Chemistry and Biotechnology, Ministry of Education, School of Biotechnology , Lihu Avenue 1800, 214122, Wuxi, China +86 51 085 328 229 ; +86 51 085 328 229 ;
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Garçon N, Silvano J, Kuper CF, Baudson N, Gérard C, Forster R, Segal L. Non-clinical safety evaluation of repeated intramuscular administration of the AS15 immunostimulant combined with various antigens in rabbits and cynomolgus monkeys. J Appl Toxicol 2015; 36:238-56. [PMID: 26032931 PMCID: PMC5033012 DOI: 10.1002/jat.3167] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/22/2014] [Revised: 03/11/2015] [Accepted: 04/03/2015] [Indexed: 12/31/2022]
Abstract
Combination of tumor antigens with immunostimulants is a promising approach in cancer immunotherapy. We assessed animal model toxicity of AS15 combined with various tumor antigens: WT1 (rabbits), or p501, dHER2 and recPRAME (cynomolgus monkeys), administered in seven or 20 dose regimens versus a saline control. Clinical and ophthalmological examinations, followed by extensive post‐mortem pathological examinations, were performed on all animals. Blood hematology and biochemistry parameters were also assessed. Antigen‐specific antibody titers were determined by enzyme‐linked immunosorbent assay. Additional assessments in monkeys included electrocardiography and immunohistochemical evaluations of the p501 expression pattern. Transient increases in body temperature were observed 4 h or 24 h after injections of recPRAME + AS15 and dHER2 + AS15. Edema and erythema were observed up to 1 week after most injections of recPRAME + AS15 and all injections of dHER2 + AS15. No treatment‐related effects were observed for electrocardiography parameters. Mean fibrinogen levels were significantly higher in all treated groups compared to controls, but no differences could be observed at the end of the treatment‐free period. Transient but significant differences in biochemistry parameters were observed post‐injection: lower albumin/globulin ratios (p501 + AS15), and higher bilirubin, urea and creatinine (dHER2 + AS15). Pathology examinations revealed significant increases in axillary lymph node mean weights (recPRAME + AS15) compared to controls. A 100% seroconversion rate was observed in all treated groups, but not in controls. p501 protein expression was observed in prostates of all monkeys from studies assessing p501 + AS15. These results suggest a favorable safety profile of the AS15‐containing candidate vaccines, supporting the use of AS15 for clinical development of potential anticancer vaccines. Copyright © 2015 The Authors. Journal of Applied Toxicology Published by John Wiley & Sons Ltd. The aim of the current paper was to assess the safety profile of vaccine candidates containing the AS15 immunostimulant combined with different antigens in two animal models. Several antigens were tested for this purpose: WT1 (rabbits), p501, dHER2 and recPRAME (cynomolgus monkeys). Only transient differences in hematology and biochemical parameters could be observed, while pathology testing revealed no safety concerns. Our findings support the use of AS15 for clinical development of potential immunotherapeutic cancer vaccines.
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Affiliation(s)
- N Garçon
- GSK Vaccines, 1300, Wavre, Belgium.,Bioaster, 321 Avenue Jean Jaurès, 69007, Lyon, France
| | - J Silvano
- CiToxLAB France, 27005, Evreux, France
| | - C F Kuper
- TNO Quality of Life, 3700, AJ Zeist, the Netherlands
| | - N Baudson
- GSK Vaccines, 1330 Rixensart, 1300, Wavre, Belgium
| | - C Gérard
- GSK Vaccines, 1330 Rixensart, 1300, Wavre, Belgium
| | - R Forster
- CiToxLAB France, 27005, Evreux, France
| | - L Segal
- GSK Vaccines, 1330 Rixensart, 1300, Wavre, Belgium
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