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T he potential and challenges of ARV-based HIV prevention: An overview. Salim S Abdool Karim Director : CAPRISA Pro Vice-Chancellor (Research): University of KwaZulu-Natal Professor in Clinical Epidemiology, Columbia University Associate Member, Ragon Institute of MGH, MIT and Harvard
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The potential and challenges of ARV-based HIV prevention:An overview Salim S Abdool Karim Director: CAPRISA Pro Vice-Chancellor (Research): University of KwaZulu-Natal Professor in Clinical Epidemiology, Columbia University Associate Member, Ragon Institute of MGH, MIT and Harvard Adjunct Professor of Medicine, Cornell University
Outline • Clinical trial evidence for ARV-based prevention • Challenges in implementing PrEP & TasP • The need for PrEP & TasP to prevent HIV in vulnerable Key Populations • Conclusion
Clinical trial evidence for ARV prophylaxis Effect size (CI) Prevention in IDUs Bangkok Tenofovir Study– daily oral Tenofovir (IDUs– Thailand) 49% (10; 72) ART for prevention HPTN052 Africa, Asia, Americas 96% (73; 99) Partners PrEP – daily Truvada (Discordant couples – Kenya, Uganda) 75% (55; 87) Partners PrEP – daily oral Tenofovir (Discordant couples – Kenya, Uganda) 67% (44; 81) TDF2 – daily Truvada (Heterosexuals men and women- Botswana) 62% (22; 84) iPrEx – daily Truvada (MSM - America’s, Thailand, South Africa) 44% (15; 63) Sexual transmission prevention CAPRISA 004 – coital Tenofovir gel (Women – South Africa) 39% (6; 60) MTN003/VOICE – daily Tenofovir gel (Women – South Africa, Uganda, Zimbabwe) 15% (-21; 40) FEMPrEP – daily Truvada (Women – Kenya, South Africa, Tanzania) 6% (-52; 41) MTN003/VOICE – daily Truvada (Women – South Africa, Uganda, Zimbabwe) -4% (-49; 27) MTN003/VOICE – daily Viread (Women - South Africa, Uganda, Zimbabwe) -49% (-129; 3) Effectiveness (%) • Source: Adapted from Abdool Karim SS.Lancet 2013
In May 2011, HPTN 052 shows that ART prevents HIV transmission from infected partners in discordant couples 1763 discordant couples in Africa & America Effect on ART (HIV +ve) on HIV: 96% (CI: 73% - 99%)
ARV prophylaxis Treatment of STIs Male circumcision Microbicides for women Grosskurth H, Lancet 2000 Auvert B, PloS Med 2005 Gray R, Lancet 2007 Bailey R, Lancet 2007 Abdool Karim Q, Science 2010 Female Condoms Male Condoms HIV PREVENTION HIV Counselling and Testing Oral pre-exposure prophylaxis Coates T, Lancet 2000 Sweat M, Lancet 2011 Grant R, NEJM 2010 (MSM) Baeten J , 2011 (Couples) Thigpen M, 2011 (Heterosexuals) Choopanya K, 2013 (IDU) Behavioural Intervention Post Exposure prophylaxis (PEP) Treatment for prevention • Abstinence • Be Faithful Cohen M, NEJM 2011 Donnell D, Lancet 2010 Tanser F, Science 2013 Scheckter M, 2002 Note: PMTCT, Screening transfusions, Harm reduction, Universal precautions, etc. have not been included – this is focused on reducing sexual transmission
July 2012: First antiretroviral approved for HIV prevention - Tenofovir + FTC
Weekly / Vol. 61/No.31 August 10, 2012 Interim Guidance for Clinicians Considering the Use of Preexposure Prophylaxis for the Prevention of HIV Infection in Heterosexually Active Adults Source: CDC. MMWR Morb Mortal Wkly Rep. 2011 and 2012
The 7 falsehoods of ARV prophylaxis to prevent HIV • PrEPshould only be used for prevention after all eligible AIDS patients are on treatment • It is not safe to give ARVs to healthy people • Asymptomatic people will not adhere to ARVs for prevention or treatment, especially when it is not provided by doctors • Data on effectiveness of PrEP, especially in women, are inconsistent & doubtful efficacy • Treatment in discordant couples ≠ community-level prevention • Drug resistance from PrEPwill undermine future AIDS treatment • PrEP will increase HIV risk by ↓condom use • We do not know how to provide PrEPand so need demonstration projects before PrEP roll-out
PrEP adherence varies by study & strongly correlates with effectiveness Pearson correlation = 0.86, p=0.003
ART by nurses is effective, sustainable and improved over time in rural SA
The 7 falsehoods of ARV prophylaxis to prevent HIV • PrEPshould only be used for prevention after all eligible AIDS patients are on treatment • It is not safe to give ARVs to healthy people • Asymptomatic people will not adhere to ARVs for prevention or treatment, especially when it is not provided by doctors • Data on effectiveness of PrEP, especially in women, are inconsistent & doubtful efficacy • Treatment in discordant couples ≠ community-level prevention • Drug resistance from PrEPwill undermine future AIDS treatment • PrEP will increase HIV risk by ↓condom use • We do not know how to provide PrEPand so need demonstration projects before PrEP roll-out
PrEP effectiveness is high in men & women with detectable tenofovir
The 7 falsehoods of ARV prophylaxis to prevent HIV • PrEPshould only be used for prevention after all eligible AIDS patients are on treatment • It is not safe to give ARVs to healthy people • Asymptomatic people will not adhere to ARVs for prevention or treatment, especially when it is not provided by doctors • Data on effectiveness of PrEP, especially in women, are inconsistent & doubtful efficacy • Trials in discordant couples ≠ community-level prevention • Drug resistance from PrEPwill undermine future AIDS treatment • PrEP will increase HIV risk by ↓condom use • We do not know how to provide PrEPand so need demonstration projects before PrEP roll-out
High ART coverage reduces HIV transmission & increases survival in a rural African community
The 7 falsehoods of ARV prophylaxis to prevent HIV • PrEPshould only be used for prevention after all eligible AIDS patients are on treatment • It is not safe to give ARVs to healthy people • Asymptomatic people will not adhere to ARVs for prevention or treatment, especially when it is not provided by doctors • Data on effectiveness of PrEP, especially in women, are inconsistent & doubtful efficacy • Trials in discordant couples ≠ community-level prevention • Drug resistance from PrEPwill undermine future AIDS treatment • PrEP will increase HIV risk by ↓condom use • We do not know how to provide PrEPand so need demonstration projects before PrEP roll-out
Drug resistance and condom use in PrEP / ART 10 8 6 4 2 0 8.2 Estimated prevalence of drug resistance after 10 years (2012–2022) 6.6 Prevalence of drug resistance 4.6 4.2 3.3 2.4 0.2 0.5 0.3 0.1 0.2 • Source: Abbas U, 2013 ART PrEP Overlapping ART + PrEP Overall ART acquired resistance ART transmitted resistance PrEP acquired resistance PrEP transmitted resistance Self-reported condom use in the CAPRISA 004 trial • Source: Adapted from Abdool Karim Q. Science 2010
The 8 falsehoods of ARV prophylaxis to prevent HIV • PrEPshould only be used for prevention after all eligible AIDS patients are on treatment • It is not safe to give ARVs to healthy people • Asymptomatic healthy people will not adhere to ARVs for prevention or treatment • Data on effectiveness of PrEP, especially in women, are inconsistent & doubtful efficacy • Trials in discordant couples ≠ community-level prevention • Drug resistance from PrEPwill undermine future AIDS treatment • PrEP will increase HIV risk by ↓condom use • We do not know how to provide PrEPand so need demonstration projects before PrEP roll-out
Early experiences with implementing PrEP in San Francisco • 49% (261/531) of eligible individuals offered PrEPin a STD clinic setting did initiate PrEP • 59% (70/118) of those referred for PrEPin a Reproductive Health program did initiate PrEP • 64% (7/11) of women with HIV+vemale partners initiated PrEPin prenatal or preconception care
Key Population 1: PrEP & TasP for young women in AfricaWomen acquire HIV ±8 years earlier than men 10 Male Female 8 1990 6 Prevalence (%) 4 2 0 <9 10-14 15-19 20-24 25-29 30-39 40-49 >49 Source: Abdool Karim Q, Abdool Karim SS, Singh B, Short R, Ngxongo S. Seroprevalence of HIV infection in rural South Africa. AIDS 1992, 6:1535-1539
High burden of HIV in young women in Africa: HIV in 15–24 year men and women (2008–2011) Young women have up to 8 times more HIV than men Zimbabwe Source: Adapted from UNAIDS 2012
Key Population 2:TasP & PrEP for MSM Source: Beyrer et al. Epidemiol Rev 2010; 32: 137-51
Key population 3: PrEP & TasP for IDUs Source: Beyrer et al. Epidemiol Rev 2010; 32: 137-51
What are the potential gains from PrEP in Key Populations? CAPRISA 004 *number needed to treat
Conclusion There is new hope in HIV prevention… • More positive trials since July 2010 than in previous 29 years • Treatment for prevention in particular provides huge hope • Microbicides and oral PrEP: Promising new HIV prevention technologies for women, MSM and IDU • Need to convert hope into actual benefit – Fast-track implementation for Key Populations