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Fonjungo PN, Lecher S, Zeh C, Rottinghaus E, Chun H, Adje-Toure C, Lloyd S, Mwangi JW, Mwasekaga M, Eshete YM, Pati R, Mots’oane T, Mitruka K, Beukes A, Mwangi C, Bowen N, Hamunime N, Beard RS, Kabuje A, Nabadda S, Auld AF, Balachandra S, Zungu I, Kandulu J, Alemnji G, Ehui E, Alexander H, Ellenberger D. Progress in scale up of HIV viral load testing in select sub-Saharan African countries 2016-2018. PLoS One 2023; 18:e0282652. [PMID: 36920918 PMCID: PMC10016655 DOI: 10.1371/journal.pone.0282652] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/30/2022] [Accepted: 02/19/2023] [Indexed: 03/16/2023] Open
Abstract
INTRODUCTION We assessed progress in HIV viral load (VL) scale up across seven sub-Saharan African (SSA) countries and discussed challenges and strategies for improving VL coverage among patients on anti-retroviral therapy (ART). METHODS A retrospective review of VL testing was conducted in Côte d'Ivoire, Kenya, Lesotho, Malawi, Namibia, Tanzania, and Uganda from January 2016 through June 2018. Data were collected and included the cumulative number of ART patients, number of patients with ≥ 1 VL test result (within the preceding 12 months), the percent of VL test results indicating viral suppression, and the mean turnaround time for VL testing. RESULTS Between 2016 and 2018, the proportion of PLHIV on ART in all 7 countries increased (range 5.7%-50.2%). During the same time period, the cumulative number of patients with one or more VL test increased from 22,996 to 917,980. Overall, viral suppression rates exceeded 85% for all countries except for Côte d'Ivoire at 78% by June 2018. Reported turnaround times for VL testing results improved in 5 out of 7 countries by between 5.4 days and 27.5 days. CONCLUSIONS These data demonstrate that remarkable progress has been made in the scale-up of HIV VL testing in the seven SSA countries.
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Affiliation(s)
- Peter N. Fonjungo
- Division of Global HIV and TB, Center for Global Health, CDC, Atlanta, Georgia, United States of America
- * E-mail:
| | - Shirley Lecher
- Division of Global HIV and TB, Center for Global Health, CDC, Atlanta, Georgia, United States of America
| | - Clement Zeh
- Division of Global HIV and TB, Center for Global Health, CDC, Atlanta, Georgia, United States of America
| | - Erin Rottinghaus
- Division of Global HIV and TB, Center for Global Health, CDC, Atlanta, Georgia, United States of America
| | - Helen Chun
- Division of Global HIV and TB, Center for Global Health, CDC, Atlanta, Georgia, United States of America
| | - Christiane Adje-Toure
- Division of Global HIV and TB, Center for Global Health, CDC, Abidjan, Côte d’Ivoire
| | - Spencer Lloyd
- Division of Global HIV and TB, Center for Global Health, CDC, Atlanta, Georgia, United States of America
| | - Jane W. Mwangi
- Division of Global HIV and TB, Center for Global Health, CDC, Nairobi, Kenya
| | - Michael Mwasekaga
- Division of Global HIV and TB, Center for Global Health, CDC, Dar es Salaam, Tanzania
| | | | - Rituparna Pati
- Division of Global HIV and TB, Center for Global Health, CDC, Atlanta, Georgia, United States of America
| | | | - Kiren Mitruka
- Division of Global HIV and TB, Center for Global Health, CDC, Atlanta, Georgia, United States of America
| | - Anita Beukes
- Namibia Institute of Pathology, Windhoek, Namibia
| | - Christina Mwangi
- Division of Global HIV and TB, Center for Global Health, CDC, Kampala, Uganda
| | | | | | - Rachel S. Beard
- Division of Global HIV and TB, Center for Global Health, CDC, Windhoek, Namibia
| | | | | | - Andrew F. Auld
- Division of Global HIV and TB, Center for Global Health, CDC, Lilongwe, Malawi
| | - Shirish Balachandra
- Division of Global HIV and TB, Center for Global Health, CDC, Abidjan, Côte d’Ivoire
| | - Innocent Zungu
- Division of Global HIV and TB, Center for Global Health, CDC, Lilongwe, Malawi
| | | | - George Alemnji
- Office of the Global AIDS Coordinator and Health Diplomacy, U.S. Department of State, Washington, DC, United States of America
| | - Eboi Ehui
- Ministry of Health, Abidjan, Côte D’Ivoire
| | - Heather Alexander
- Division of Global HIV and TB, Center for Global Health, CDC, Atlanta, Georgia, United States of America
| | - Dennis Ellenberger
- Division of Global HIV and TB, Center for Global Health, CDC, Atlanta, Georgia, United States of America
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Santoro MM, Perno CF. HIV-1 Genetic Variability and Clinical Implications. ISRN MICROBIOLOGY 2013; 2013:481314. [PMID: 23844315 PMCID: PMC3703378 DOI: 10.1155/2013/481314] [Citation(s) in RCA: 101] [Impact Index Per Article: 9.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 03/24/2013] [Accepted: 04/16/2013] [Indexed: 11/29/2022]
Abstract
Despite advances in antiretroviral therapy that have revolutionized HIV disease management, effective control of the HIV infection pandemic remains elusive. Beyond the classic non-B endemic areas, HIV-1 non-B subtype infections are sharply increasing in previous subtype B homogeneous areas such as Europe and North America. As already known, several studies have shown that, among non-B subtypes, subtypes C and D were found to be more aggressive in terms of disease progression. Luckily, the response to antiretrovirals against HIV-1 seems to be similar among different subtypes, but these results are mainly based on small or poorly designed studies. On the other hand, differences in rates of acquisition of resistance among non-B subtypes are already being observed. This different propensity, beyond the type of treatment regimens used, as well as access to viral load testing in non-B endemic areas seems to be due to HIV-1 clade specific peculiarities. Indeed, some non-B subtypes are proved to be more prone to develop resistance compared to B subtype. This phenomenon can be related to the presence of subtype-specific polymorphisms, different codon usage, and/or subtype-specific RNA templates. This review aims to provide a complete picture of HIV-1 genetic diversity and its implications for HIV-1 disease spread, effectiveness of therapies, and drug resistance development.
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Affiliation(s)
- Maria Mercedes Santoro
- Department of Experimental Medicine and Surgery, University of Rome Tor Vergata, Via Montpellier 1, 00133 Rome, Italy
| | - Carlo Federico Perno
- Department of Experimental Medicine and Surgery, University of Rome Tor Vergata, Via Montpellier 1, 00133 Rome, Italy
- INMI L Spallanzani Hospital, Antiretroviral Therapy Monitoring Unit, Via Portuense 292, 00149 Rome, Italy
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The Impact of HIV Genetic Polymorphisms and Subtype Differences on the Occurrence of Resistance to Antiretroviral Drugs. Mol Biol Int 2012; 2012:256982. [PMID: 22792462 PMCID: PMC3390109 DOI: 10.1155/2012/256982] [Citation(s) in RCA: 47] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/28/2012] [Accepted: 04/12/2012] [Indexed: 12/20/2022] Open
Abstract
The vast majority of reports on drug resistance deal with subtype B infections in developed countries, and this is largely due to historical delays in access to antiretroviral therapy (ART) on a worldwide basis. This notwithstanding the concept that naturally occurring polymorphisms among different non-B subtypes can affect HIV-1 susceptibility to antiretroviral drugs (ARVs) is supported by both enzymatic and virological data. These findings suggest that such polymorphisms can affect both the magnitude of resistance conferred by some major mutations as well as the propensity to acquire certain resistance mutations, even though such differences are sometimes difficult to demonstrate in phenotypic assays. It is mandatory that tools are optimized to assure accurate measurements of drug susceptibility in non-B subtypes and to recognize that each subtype may have a distinct resistance profile and that differences in resistance pathways may also impact on cross-resistance and the choice of regimens to be used in second-line therapy. Although responsiveness to first-line therapy should not theoretically be affected by considerations of viral subtype and drug resistance, well-designed long-term longitudinal studies involving patients infected by viruses of different subtypes should be carried out.
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Affiliation(s)
- Mark A Wainberg
- McGill University AIDS Centre, Lady Davis Institute, Jewish General Hospital, Montreal, QC H3T 1E2, Canada.
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Replicative fitness costs of nonnucleoside reverse transcriptase inhibitor drug resistance mutations on HIV subtype C. Antimicrob Agents Chemother 2011; 55:2146-53. [PMID: 21402856 DOI: 10.1128/aac.01505-10] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Single-dose nevirapine (NVP) is quite effective in preventing transmission of the human immunodeficiency virus (HIV) from mother to child; however, many women develop resistance to NVP in this setting. Comparing outcomes of clinical studies reveals an increased amount of resistance in subtype C relative to that in other subtypes. This study investigates how nonnucleoside reverse transcriptase inhibitor (NNRTI) drug resistance mutations of subtype C affect replication capacity. The 103N, 106A, 106M, 181C, 188C, 188L, and 190A drug resistance mutations were placed in a reverse transcriptase (RT) that matches the consensus subtype C sequence as well as the HXB2 RT, as a subtype B reference. The replicative fitness of each mutant was compared with that of the wild type in a head-to-head competition assay. The 106A mutant of subtype C would not grow in the competition assay, making it the weakest virus tested. The effect of the 106M mutation was weaker than those of the 181C and 188C mutations in the consensus C RT, but in subtype B, this difference was not seen. To see if the 106A mutation in a different subtype C background would have a different replicative profile, the same NNRTI resistance mutations were added to the MJ4 RT, a reference subtype C molecular clone. In the context of MJ4 RT, the 106A mutant was not the only mutant that showed poor replicative fitness; the 106M, 188C, and 190A mutants also failed to replicate. These results suggest that NNRTIs may be a cost-effective alternative for salvage therapy if deleterious mutations are present in a subtype C setting.
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Wainberg MA, Brenner BG. Role of HIV Subtype Diversity in the Development of Resistance to Antiviral Drugs. Viruses 2010; 2:2493-508. [PMID: 21994627 PMCID: PMC3185584 DOI: 10.3390/v2112493] [Citation(s) in RCA: 30] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/08/2010] [Revised: 10/26/2010] [Accepted: 10/28/2010] [Indexed: 12/13/2022] Open
Abstract
Despite the fact that over 90% of HIV-1 infected people worldwide harbor non-subtype B variants of HIV-1, knowledge of resistance mutations in non-B HIV-1 and their clinical relevance is limited. Due to historical delays in access to antiretroviral therapy (ART) on a worldwide basis, the vast majority of reports on drug resistance deal with subtype B infections in developed countries. However, both enzymatic and virological data support the concept that naturally occurring polymorphisms among different nonB subtypes can affect HIV-1 susceptibility to antiretroviral drugs (ARVs), the magnitude of resistance conferred by major mutations, and the propensity to acquire some resistance mutations. Tools need to be optimized to assure accurate measurements of drug susceptibility of non-B subtypes. Furthermore, there is a need to recognize that each subtype may have a distinct resistance profile and that differences in resistance pathways may also impact on cross-resistance and the selection of second-line regimens. It will be essential to pay attention to newer drug combinations in well designed long-term longitudinal studies involving patients infected by viruses of different subtypes.
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Affiliation(s)
- Mark A Wainberg
- McGill University AIDS Centre, Jewish General Hospital, 3755 Cote-Ste-Catherine Road, Montreal, Quebec, H3T 1E2, Canada; E-Mail:
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Rowley CF, Boutwell CL, Lee EJ, MacLeod IJ, Ribaudo HJ, Essex M, Lockman S. Ultrasensitive detection of minor drug-resistant variants for HIV after nevirapine exposure using allele-specific PCR: clinical significance. AIDS Res Hum Retroviruses 2010; 26:293-300. [PMID: 20334564 DOI: 10.1089/aid.2009.0082] [Citation(s) in RCA: 29] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
Abstract
HIV-1 drug resistance mutations have been detected at low frequencies after single-dose nevirapine (sdNVP) for prevention of mother-to-child transmission (PMTCT). We investigated the relationship between these "minor variant" NVP-resistant viruses and clinical outcome with NVP-containing antiretroviral therapy (ART). An allele-specific quantitative PCR (ASPCR) assay was used to quantify the pre-ART frequency of K103N and Y181C in 26 women who had received sdNVP. The cohort was composed of 7 patients who experienced virologic failure and 19 control patients who maintained virologic suppression on NVP-containing ART; all were negative for resistance by standard genotyping. NVP resistance mutations were found in 17 of 26 (65%) patients using ASPCR. The frequency of NVP-resistant viruses ranged from 0.1% to 4.11%. Receiver operating characteristics (ROC) analysis identified a clinical threshold frequency of 0.19% for the ASPCR assay. Application of this threshold demonstrated minor variant resistance in 6 of 7 patients (86%) who failed treatment compared to 6 of 19 patients (32%) who were successful (OR = 13; 95% CI 1.27-133). ASPCR provides a means of detecting minor variant drug-resistant viruses that may impact subsequent treatment response. These data suggest a clinical role for highly sensitive assays to detect and quantify resistant viruses at low frequencies.
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Affiliation(s)
- Christopher F. Rowley
- Division of Infectious Diseases, Beth Israel Deaconess Medical Center, Boston, Massachusetts
- Department of Immunology and Infectious Diseases, Harvard School of Public Health, Boston, Massachusetts
- Harvard School of Public Health AIDS Initiative, Boston, Massachusetts
| | - Christian L. Boutwell
- Department of Immunology and Infectious Diseases, Harvard School of Public Health, Boston, Massachusetts
| | - Esther J. Lee
- Department of Immunology and Infectious Diseases, Harvard School of Public Health, Boston, Massachusetts
- Harvard School of Public Health AIDS Initiative, Boston, Massachusetts
| | - Iain J. MacLeod
- Department of Immunology and Infectious Diseases, Harvard School of Public Health, Boston, Massachusetts
| | - Heather J. Ribaudo
- Center for Biostatistics in AIDS Research, Harvard School of Public Health, Boston, Massachusetts
| | - M. Essex
- Harvard School of Public Health AIDS Initiative, Boston, Massachusetts
| | - Shahin Lockman
- Department of Immunology and Infectious Diseases, Harvard School of Public Health, Boston, Massachusetts
- Harvard School of Public Health AIDS Initiative, Boston, Massachusetts
- Division of Infectious Diseases, Brigham and Women's Hospital, Boston, Massachusetts
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Resistance and viral subtypes: how important are the differences and why do they occur? Curr Opin HIV AIDS 2009; 2:94-102. [PMID: 19372873 DOI: 10.1097/coh.0b013e32801682e2] [Citation(s) in RCA: 28] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022]
Abstract
PURPOSE OF REVIEW The global HIV-1 pandemic has evolved to include 11 subtypes and 34 circulating recombinant forms. Our knowledge of HIV-1 response to antiretroviral drugs and emergent drug resistance has, however, been limited to subtype B infections circulating in Europe and North America, with little comparative information on non-B subtypes representing approximately 90% of worldwide epidemics. This review summarizes publications in the past year that highlight intersubtype differences influencing viral susceptibility to antiretroviral drugs and emergent drug resistance. RECENT FINDINGS Cumulative findings from clinical studies suggest that antiretroviral therapy will be of benefit in the overall treatment of non-B subtype infections, and result in drug-resistance profiles comparable to those observed for subtype B infections. Nevertheless, the 10-15% sequence diversity in the Pol region contributes to intersubtype differences in response to particular nucleoside and non-nucleoside analogues, as well as protease inhibitors. Distinct signature mutations and mutational pathways are identified for specific non-B subtypes. The implications of subtype on clinical outcome and interpretative algorithms are described. SUMMARY Understanding intersubtype differences in drug resistance is important in optimizing treatment strategies in resource-poor settings. Hopefully, this may assist in the design of prophylactic approaches to prevent HIV-1 horizontal and vertical HIV-1 transmission.
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Musiime V, Ssali F, Kayiwa J, Namala W, Kizito H, Kityo C, Mugyenyi P. Response to nonnucleoside reverse transcriptase inhibitor-based therapy in HIV-infected children with perinatal exposure to single-dose nevirapine. AIDS Res Hum Retroviruses 2009; 25:989-96. [PMID: 19778270 DOI: 10.1089/aid.2009.0054] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
Abstract
We set out to investigate whether there are clinically significant consequences when children with perinatal exposure to single-dose nevirapine are initiated on a nonnucleoside reverse transcriptase inhibitor (NNRTI) containing a highly active antiretroviral therapy (HAART) regimen. We carried out a chart and database review of 104 HIV-infected children, who had initiated HAART with an NNRTI at JCRC and were less than or equal to 5 years of age, 35 (33.7%) of whom had prior exposure to perinatal single-dose nevirapine. We studied the viral load and CD4 percentage at baseline, at week 24, and at week 48 after the start of HAART in children exposed and not exposed to perinatal single-dose nevirapine, as well as the results of genotypic resistance testing done for the children who had failed to achieve virologic suppression on HAART. At weeks 24 and 48 after initiating HAART, children not exposed to single-dose nevirapine were 3.28 times [OR = 3.28, 95% CI: (1.37 to 9.20), p = 0.0167] and 3.47 times [OR = 3.47, 95% CI: (1.28 to 9.37), p = 0.0091] more likely to achieve virologic suppression compared to children exposed to single-dose nevirapine, respectively. However, the CD4 cell response at weeks 24 and 48 was not worse in the children exposed to single-dose nevirapine. In 10 children with perinatal exposure to single-dose nevirapine, NNRTI resistance mutations, mostly K103N, Y181C, and G109A, were identified. HIV-infected children with perinatal exposure to single-dose nevirapine are less likely to achieve short-term virologic suppression when started on an NNRTI-containing regimen, when compared to those who were not exposed to it, probably because the exposure predisposes them to developing NNRTI resistance mutations.
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Affiliation(s)
- Victor Musiime
- Joint Clinical Research Centre (JCRC), Butikiro House, Kampala, Uganda
| | - Francis Ssali
- Joint Clinical Research Centre (JCRC), Butikiro House, Kampala, Uganda
| | - Joshua Kayiwa
- Joint Clinical Research Centre (JCRC), Butikiro House, Kampala, Uganda
| | - Winnie Namala
- Joint Clinical Research Centre (JCRC), Butikiro House, Kampala, Uganda
| | - Hilda Kizito
- Joint Clinical Research Centre (JCRC), Butikiro House, Kampala, Uganda
| | - Cissy Kityo
- Joint Clinical Research Centre (JCRC), Butikiro House, Kampala, Uganda
| | - Peter Mugyenyi
- Joint Clinical Research Centre (JCRC), Butikiro House, Kampala, Uganda
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Kiptoo M, Ichimura H, Wembe RL, Ng'Ang'a Z, Mueke J, Kinyua J, Lagat N, Okoth F, Songok E. Prevalence of nevirapine-associated resistance mutations after single dose prophylactic treatment among antenatal clinic attendees in north rift Kenya. AIDS Res Hum Retroviruses 2008; 24:1555-9. [PMID: 19102687 DOI: 10.1089/aid.2008.0018] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
Abstract
The use of single dose nevirapine to prevent mother-to-child transmission of HIV has been reported to induce drug-resistant mutations and reduce options for antiretroviral treatment for HIV-infected mothers and their children. To explore the status of nevirapine-resistant HIV genotypes in rural hospitals in the North Rift Valley Province of Kenya, samples collected 3 months after single dose nevirapine from 36 mothers and their children were analyzed. Resistance mutations were genotypically evaluated through proviral DNA amplification, cloning, and sequencing. Ten mothers (27.8%) had antiretroviral-associated resistance mutations of whom four (11.1%) had specific nevirapine (NNRTI) resistance-associated mutations. Three mothers (8.3%) transmitted the infection to their infants. This presence of nevirapine mutations in rural antenatal clinic attendees confirms the importance of integrating antiretroviral resistance monitoring as a key component in programs geared to prevention of HIV mother-to-child transmission.
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Affiliation(s)
- Michael Kiptoo
- Centre for Virus Research, Kenya Medical Research Institute, Nairobi, Kenya
- Department of Biological Sciences, Kenyatta University, Nairobi, Kenya
| | - Hiroshi Ichimura
- Department of Viral Infections, Graduate School of Medical Science, Kanazawa University, Kanazawa, Japan
| | - Raphael L. Wembe
- Centre for Virus Research, Kenya Medical Research Institute, Nairobi, Kenya
- Department of Viral Infections, Graduate School of Medical Science, Kanazawa University, Kanazawa, Japan
| | - Zipporah Ng'Ang'a
- Department of Biological Sciences, Kenyatta University, Nairobi, Kenya
| | - Jones Mueke
- Department of Biological Sciences, Kenyatta University, Nairobi, Kenya
| | - Joyceline Kinyua
- Centre for Virus Research, Kenya Medical Research Institute, Nairobi, Kenya
| | - Nancy Lagat
- Centre for Virus Research, Kenya Medical Research Institute, Nairobi, Kenya
| | - Fredrick Okoth
- Centre for Virus Research, Kenya Medical Research Institute, Nairobi, Kenya
| | - E.M. Songok
- Centre for Virus Research, Kenya Medical Research Institute, Nairobi, Kenya
- Department of Biological Sciences, Kenyatta University, Nairobi, Kenya
- Department of Medical Microbiology and Infectious Diseases, University of Manitoba, Manitoba, Canada
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Soares MA. Drug resistance differences among HIV types and subtypes: a growing problem. ACTA ACUST UNITED AC 2008. [DOI: 10.2217/17469600.2.6.579] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
Although HIV-1 subtype B accounts for only 10% of worldwide HIV infections, almost all knowledge regarding antiretroviral (ARV) drug development and viral resistance is based on this subtype. More recently, an increasing body of evidence suggests that distinct HIV genetic variants possess different biological properties, including susceptibility and response to ARVs. In this review, we will summarize recent in vitro and in vivo studies reporting such differences. In general terms, infections with most HIV variants respond well to ARVs, but minor differences in susceptibility, in the emergence and selection of subtype-specific drug resistance mutations and in the acquisition of similar mutations over the period of ARV exposure have been reported. Such differences impact on drugresistance interpretation algorithms, which are mostly based on inference from sequence information. Despite the differences observed, clinical response to ARV therapy among subjects infected with distinct HIV variants is effective, and the dissemination of ARV access in developing countries where non-B subtypes prevail should not be delayed.
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Affiliation(s)
- Marcelo A Soares
- Departamento de Genética, Universidade Federal do Rio de Janeiro, Divisão de Genética, Instituto Nacional de Câncer CCS, Bloco A, sala A2–120, Cidade Universitária, Ilha do Fundão, 21949-570, Rio de Janeiro, Brazil
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12
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Hamers RL, Derdelinckx I, van Vugt M, Stevens W, Rinke de Wit TF, Schuurman R. The Status of HIV-1 Resistance to Antiretroviral drugs in Sub-Saharan Africa. Antivir Ther 2008. [DOI: 10.1177/135965350801300502] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
Abstract
Access to highly active antiretroviral therapy (HAART) for persons infected with HIV in sub-Saharan Africa has greatly improved over the past few years. However, data on long-term clinical outcomes of Africans receiving HAART, patterns of HIV resistance to antiretroviral drugs and implications of HIV type-1 (HIV-1) subtype diversity in Africa for resistance, are limited. In resource-limited settings, concerns have been raised that deficiencies in health systems could create the conditions for accelerated development of resistance. Coordinated surveillance systems are being established to assess the emergence of resistance and the factors associated with resistance development, and to create the possibility for adjusting treatment guidelines as necessary. The purpose of this report is to review the literature on HIV-1 resistance to antiretroviral drugs in sub-Saharan Africa, in relation to the drug regimens used in Africa, HIV-1 subtype diversity and overall prevalence of resistance. The report focuses on resistance associated with treatment, prevention of mother-to-child transmission and transmitted resistance. It also outlines priorities for public health action and research.
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Affiliation(s)
- Raph L Hamers
- PharmAccess Foundation, Center for Poverty-Related Communicable Diseases, Academic Medical Center, University of Amsterdam, Amsterdam, The Netherlands
| | - Inge Derdelinckx
- Department of Medical Microbiology, University Medical Center Utrecht, Utrecht, The Netherlands
| | - Michèle van Vugt
- PharmAccess Foundation, Center for Poverty-Related Communicable Diseases, Academic Medical Center, University of Amsterdam, Amsterdam, The Netherlands
- Division of Infectious Diseases, Tropical Medicine and AIDS, Academic Medical Center, University of Amsterdam, Amsterdam, The Netherlands
| | - Wendy Stevens
- Department of Molecular Medicine and Haematology, University of the Witwatersrand, Johannesburg, South Africa
| | - Tobias F Rinke de Wit
- PharmAccess Foundation, Center for Poverty-Related Communicable Diseases, Academic Medical Center, University of Amsterdam, Amsterdam, The Netherlands
| | - Rob Schuurman
- Department of Medical Microbiology, University Medical Center Utrecht, Utrecht, The Netherlands
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Turriziani O, Russo G, Lichtner M, Stano A, Tsague G, Maida P, Vullo V, Antonelli G. Study of the genotypic resistant pattern in HIV-infected women and children from rural west Cameroon. AIDS Res Hum Retroviruses 2008; 24:781-5. [PMID: 18507527 DOI: 10.1089/aid.2007.0213] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
Abstract
The distribution of antiretroviral (ARV) therapy resistance mutations among HIV-1 strains was evaluated in 39 postpartum women, one pregnant woman, and 12 HIV-positive babies (seven newborns and five children) living in rural west Cameroon. Thirty-five women and all newborns received a single dose of nevirapine (NVP) to prevent mother-to-child transmission of HIV-1; two women were ARV treated and three were ARV naive. Of the 52 viral strains examined, three were subtype B, 45 were classified into eight HIV-1 non-B subtypes, and four remained unclassifiable. Sequence analysis for genotypic drug resistance in the reverse transcriptase (RT) gene showed the presence of mutations associated with nonnucleoside RT inhibitor resistance in 20% of the samples from NVP-treated women and in 57% of those from treated newborns. Mutations associated with nucleoside RT inhibitors (M184V in one case and V118I in four cases) were found in five samples, despite being derived from ARV-naive patients. As expected, a greater frequency of mutations was found in the protease gene region. Of the sequences analyzed, 79% harbored five to seven specific mutations. The secondary mutations showed the typical protease inhibitor resistance-associated pattern for non-subtype B viruses, M36I being the predominant mutation (92.5% in women, 100% in babies). Other mutations frequently detected were K20I, L63P, H69K, and I13V. These findings confirm that resistance mutations can be detected in ARV-naive patients infected with non-B subtypes and emphasize an urgent need for studies assessing the impact of these mutations on the efficacy of subsequent ARV therapy and on the appearance of drug-resistant strains.
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Affiliation(s)
- Ombretta Turriziani
- Department of Experimental Medicine, Virology Section, “Sapienza” University of Rome, Rome, Italy
| | - Gianluca Russo
- Department of Infectious and Tropical Diseases, “Sapienza” University of Rome, Rome, Italy
| | - Miriam Lichtner
- Department of Infectious and Tropical Diseases, “Sapienza” University of Rome, Rome, Italy
| | - Armando Stano
- Department of Experimental Medicine, Virology Section, “Sapienza” University of Rome, Rome, Italy
| | | | - Paola Maida
- Department of Experimental Medicine, Virology Section, “Sapienza” University of Rome, Rome, Italy
| | - Vincenzo Vullo
- Department of Infectious and Tropical Diseases, “Sapienza” University of Rome, Rome, Italy
| | - Guido Antonelli
- Department of Experimental Medicine, Virology Section, “Sapienza” University of Rome, Rome, Italy
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Ly N, Phoung V, Min DC, Srey C, Kruy LS, Koum K, Chhum V, Glaziou P, Fleury HJ, Reynes JM. Reverse transcriptase mutations in Cambodian CRF01_AE isolates after antiretroviral prophylaxis against HIV Type 1 perinatal transmission. AIDS Res Hum Retroviruses 2007; 23:1563-8. [PMID: 18160014 DOI: 10.1089/aid.2007.0100] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
Abstract
This study explores amino acid changes of the reverse transcriptase (rt) of CRF01_AE isolates from pregnant women naive to antiretroviral drugs before and 2, 6, and 52 weeks after exposure to single dose nevirapine (sdNVP). Results based on 51 observations showed that the proportion of isolates with nonnucleoside reverse transcriptase inhibitor (NNRTI) RMs in the group treated with sdNVP (n = 35) increased from 0% pre-NVP to 22.9% at week 2 postpartum (pp) and 22.9% at week 6 pp. In the group treated with zidovudine + sdNVP (n = 16), the proportion with RM was 31.3% and 18.8% at weeks 2 and 6 pp, respectively. Only a few RMs were still detected at week 52 pp. No apparent subtype-specific treatment-related mutations were detected. NNRTI RM occurrence in CRF01_AE strains is similar to subtype A, D, and CRF02_AG strains after exposure to antiretroviral drugs for PMTCT.
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Affiliation(s)
- Nary Ly
- Institut Pasteur du Cambodge, Phnom Penh, Cambodia
| | | | | | | | | | - Kanal Koum
- National Maternal and Child Health Center, Phnom Penh, Cambodia
| | | | | | - Hervé J. Fleury
- Laboratoire de Virologie EA 2968, Université Victor Ségalen, Bordeaux 2, Bordeaux, France
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15
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Arrivé E, Newell ML, Ekouevi DK, Chaix ML, Thiebaut R, Masquelier B, Leroy V, Perre PVD, Rouzioux C, Dabis F. Prevalence of resistance to nevirapine in mothers and children after single-dose exposure to prevent vertical transmission of HIV-1: a meta-analysis. Int J Epidemiol 2007; 36:1009-21. [PMID: 17533166 DOI: 10.1093/ije/dym104] [Citation(s) in RCA: 179] [Impact Index Per Article: 10.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Abstract
BACKGROUND Single-dose nevirapine (NVP) is the main option for the prevention of mother-to-child transmission (PMTCT) of HIV-1 in countries with limited resources. However, the use of single-dose NVP results in HIV-1 viral resistance which could compromise the success of subsequent treatment of mother and child with antiretroviral combinations that include non-nucleosidic-reverse-transcriptase inhibitors. This systematic review and meta-analysis of summarized data aimed to estimate the proportion of mothers and children with NVP resistance mutations detected in plasma samples 4-8 weeks postpartum after single-dose NVP use for PMTCT. METHODS Systematic search of electronic databases (MEDLINE, PASCAL) and conference proceedings (1997 to February 2006). Inclusion of all studies, without design, place or language restrictions, meeting the following criteria: use of single-dose NVP; viral genotyping performed with standard sequence analyses, between 4 and 8 weeks postpartum, in plasma samples; available public report; report of mothers' median baseline plasma HIV-1 RNA levels. Data extraction by two independent reviewers using a standardized form created for this purpose. Logistic random effect models to obtain pooled estimates. Univariable and multivariable meta-regression to explore sources of heterogeneity. RESULTS The pooled estimate of NVP resistance prevalence was 35.7% [95% confidence interval (CI) 23.0-50.6] in women in 10 study arms using single-dose NVP +/- other antepartum antiretrovirals and 4.5% (CI 2.1-9.4) in three study arms providing also postpartum antiretrovirals (adjusted odds ratio 0.08; CI 0.04-0.16). The corresponding estimates in children were 52.6% (CI 37.7-67.0) in seven study arms using single-dose NVP only and 16.5% (CI 8.9-28.3) in eight study arms combining single-dose NVP with other antiretrovirals. CONCLUSIONS Single-dose NVP is widely used for PMTCT in resource-poor settings, but the burden of viral resistance is high in both women and children. It is substantially lower in studies providing additional postpartum antiretrovirals. The clinical implications of these findings should be further investigated.
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16
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Abstract
PURPOSE OF REVIEW HIV knowledge is based on subtype B, common in resource-rich settings, whereas globally non-B subtypes predominate. Inter-subtype pol diversity encompasses multiple genotypic differences among HIV variants, the consequence of which is unknown. This review summarizes publications from the past year relevant to the impact of HIV diversity on drug resistance evolution and its potential clinical implications. RECENT FINDINGS The benefit of antiretroviral therapy in non-B infected patients is ongoing, though subtype heterogeneity in rates of disease progression is observed. Pol inter-subtype diversity is high, and known subtype B drug resistance mutations occur in non-B subtypes. New mutations and subtype-specific mutation rates are identified, however, unexplained drug susceptibilities are seen, and additional insight is offered on structural pathogenic mechanisms of resistance in non-B subtypes. These differences may affect genotypic interpretation and our ability to apply drug resistance to patient care. SUMMARY Current evidence suggests good treatment response and comparable drug resistance evolution in HIV-1 B and non-B infected patients, with increasingly emerging differences. Impact of inter-subtype diversity on drug susceptibility and on evolution of drug resistance should continue to be a major research focus to increase our understanding and ability to improve global patient care.
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Affiliation(s)
- Rami Kantor
- Division of Infectious Diseases, The Miriam Hospital, Providence, Rhode Island 02906, USA.
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17
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Abstract
The HIV-1 pandemic is a complex mix of diverse epidemics within and between countries and regions of the world, and is undoubtedly the defining public-health crisis of our time. Research has deepened our understanding of how the virus replicates, manipulates, and hides in an infected person. Although our understanding of pathogenesis and transmission dynamics has become more nuanced and prevention options have expanded, a cure or protective vaccine remains elusive. Antiretroviral treatment has transformed AIDS from an inevitably fatal condition to a chronic, manageable disease in some settings. This transformation has yet to be realised in those parts of the world that continue to bear a disproportionate burden of new HIV-1 infections and are most affected by increasing morbidity and mortality. This Seminar provides an update on epidemiology, pathogenesis, treatment, and prevention interventions pertinent to HIV-1.
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Affiliation(s)
- Viviana Simon
- Aaron Diamond AIDS Research Center, The Rockefeller University, New York, NY, USA.
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18
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Baggaley RF, Garnett GP, Ferguson NM. Modelling the impact of antiretroviral use in resource-poor settings. PLoS Med 2006; 3:e124. [PMID: 16519553 PMCID: PMC1395349 DOI: 10.1371/journal.pmed.0030124] [Citation(s) in RCA: 123] [Impact Index Per Article: 6.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/05/2005] [Accepted: 01/09/2006] [Indexed: 12/02/2022] Open
Abstract
BACKGROUND The anticipated scale-up of antiretroviral therapy (ART) in high-prevalence, resource-constrained settings requires operational research to guide policy on the design of treatment programmes. Mathematical models can explore the potential impacts of various treatment strategies, including timing of treatment initiation and provision of laboratory monitoring facilities, to complement evidence from pilot programmes. METHODS AND FINDINGS A deterministic model of HIV transmission incorporating ART and stratifying infection progression into stages was constructed. The impact of ART was evaluated for various scenarios and treatment strategies, with different levels of coverage, patient eligibility, and other parameter values. These strategies included the provision of laboratory facilities that perform CD4 counts and viral load testing, and the timing of the stage of infection at which treatment is initiated. In our analysis, unlimited ART provision initiated at late-stage infection (AIDS) increased prevalence of HIV infection. The effect of additionally treating pre-AIDS patients depended on the behaviour change of treated patients. Different coverage levels for ART do not affect benefits such as life-years gained per person-year of treatment and have minimal effect on infections averted when treating AIDS patients only. Scaling up treatment of pre-AIDS patients resulted in more infections being averted per person-year of treatment, but the absolute number of infections averted remained small. As coverage increased in the models, the emergence and risk of spread of drug resistance increased. Withdrawal of failing treatment (clinical resurgence of symptoms), immunologic (CD4 count decline), or virologic failure (viral rebound) increased the number of infected individuals who could benefit from ART, but effectiveness per person is compromised. Only withdrawal at a very early stage of treatment failure, soon after viral rebound, would have a substantial impact on emergence of drug resistance. CONCLUSIONS Our analysis found that ART cannot be seen as a direct transmission prevention measure, regardless of the degree of coverage. Counselling of patients to promote safe sexual practices is essential and must aim to effect long-term change. The chief aims of an ART programme, such as maximised number of patients treated or optimised treatment per patient, will determine which treatment strategy is most effective.
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Affiliation(s)
- Rebecca F Baggaley
- Department of Infectious Disease Epidemiology, Imperial College London, United Kingdom.
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