1 / 35

Does Africa need a rectal microbicide?

Does Africa need a rectal microbicide?. IRMA and AVAC presentation 27 September 2011 Salim S. Abdool Karim Pro Vice-Chancellor (Research), University of KwaZulu-Natal Director: CAPRISA Professor of Clinical Epidemiology, Columbia University

ace
Download Presentation

Does Africa need a rectal microbicide?

An Image/Link below is provided (as is) to download presentation Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author. Content is provided to you AS IS for your information and personal use only. Download presentation by click this link. While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server. During download, if you can't get a presentation, the file might be deleted by the publisher.

E N D

Presentation Transcript


  1. Does Africa need a rectal microbicide? IRMA and AVAC presentation 27 September 2011 Salim S. Abdool Karim Pro Vice-Chancellor (Research), University of KwaZulu-Natal Director: CAPRISA Professor of Clinical Epidemiology, Columbia University Adjunct Professor of Medicine, Cornell University Associate Member, The Ragon Institute of MGH, MIT and Harvard University

  2. Outline • The HIV epidemic in Africa • Prevalence of HIV in MSM • Rates of bisexual partnerships • Prevalence of anal sex • Risk factors for unprotected anal intercourse • A new hope… • Conclusion

  3. HIV prevalence in pregnant women in rural Vulindlela, South Africa (2005-2008)

  4. The HIV epidemic in Africa:HIV prevalence by age and sex in four African countries Kenya Malawi Lesotho Cameroon

  5. The HIV epidemic in Africa: The hidden sideAfrican Men who have Sex with Men • Population-level data on MSM are rare • same-sex relations are criminalized in 37 out of 54 African countries and are punishable by death in four of these. • Recent studies on MSM sex workers indicates widespread existence of MSM groups in Africa • Mombasa, Kenya: ± 739 MSM sex workers working in the city • Johannesburg, South Africa: ± 496 MSM sex workers (95% CI 437–555) working in city on any given Saturday night

  6. The HIV epidemic in Africa:A mosiac of both heterosexual and homosexual HIV transmission Source: UNAIDS. 2006 Report on the global AIDS epidemic. UNAIDS, Geneva

  7. HIV prevalence among MSM in Africa HIV prevalence in MSM: Range: 6.2% in Egypt to 30.9% in Cape Town Source: Griensven et al. Current Opinion in HIV and AIDS 2009, 4:300–307

  8. Estimates of HIV prevalence among MSM in sub-Saharan Africa Adapted from: Smith AD, et al. Men who have sex with men and HIV/AIDS in sub-Saharan Africa. Lancet 2009; 374: 416–22

  9. Factors associated with HIV infection among MSM • In South Africa • Soweto Men's Study (N=378) HIV infection associated with: • 6-9 partners (past 6 months) (OR 5.7, CI 4.0-8.2) • any unprotected anal sex* (OR 4.4, CI 3.5-5.7) *past 6 months • In Kenya • Prevalent HIV infection in MSM (n=285) was associated with: • recent receptive anal sex (OR, 6.1; CI, 2.4-16) • exclusive sex with men (OR, 6.3; CI, 2.3-17),

  10. Rates of bisexual partnerships in Africa • In Malawi, Namibia and Botswana • cross-sectional study of MSM (n=537) showed: • 34.1% were married or had a stable female partner, • 53.7% had both male and female sexual partners • In Egypt • Survey among MSM (n=73) showed: • 73.3% of MSM reported being bisexual • In Kampala, Uganda • Survey among MSM (n=224) reported: • 39% self-identified as "bisexual”

  11. Studies providing estimates of heterosexual sex among MSM (2003–2007) Source: Caceres, C. F., et al. (2008). Sex Transm Infect 84 Suppl 1: i49-i56.

  12. Anal intercourse in heterosexual men & women • In Cape Town, South Africa: • Anonymous surveys of 2593 men and 1818 women: • Anal intercourse (past 3 months): Men = 14%; Women = 10% • Condom use during anal intercourse: Men = 67%; Women = 50% Kalichman et al (2009) • In KwaZulu-Natal, South Africa: • 42% of truck drivers (n=320) reported anal sex with female sex workers Ramjee et al (2002) • In Kenya: • Survey among FSW (n=147): • 40.8% reported ever practising anal intercourse, 30% reported never or rarely using condoms during anal intercourse • consistent condom use lower in anal sex than peno-vaginal intercourse Schwandt et al (2006) • In Nigeria: • anal sex practiced by 12% of public secondary schools students (N= 521) Bamidele et al (2009)

  13. Factors associated with unprotected anal intercourse (UAI) in Africa • Cameroon: UAI risk increased in those not knowing any HIV-infected person (N=168, OR 1.89) Henry et al (2010) • South Africa: UAI risk associated with regular drinking (N=147; OR 4.1) Lane et al. (2008) • Uganda: UAI associated with having had an HIV test in the past 6 months (N=215, OR 2.81) Raymond et al (2009) • Kenya: UAI linked to poor knowledge of increased HIV risk from UAI (N=425, OR: 1.9) Geibel et al. (2008)

  14. Risks associated with unprotected anal intercourse: HIV transmission Source: Baggaley et al. Int. J. Epidemiol. Advance Access published April 20, 2010

  15. A new hope…

  16. July 2010: Proof of Concept for microbicides 1st class: Surfactants eg. N9, SAVVY 2nd class: Polymers eg. PRO2000, Carraguard, Cellulose Sulfate (CS) 3rd class: ARVs eg. Tenofovir gel CAPRISA 004 Tenofovir gel trial Kenya N-9 sponge trial CONRAD CS trial FHI CS Trial MTN003 –VOICE Tenofovir gel & tablet trial FHI N-9 film trial PopCouncil Carraguard trial FACTS 001 Tenofovir gel trial UNAIDS COL-1492 trial HPTN PRO2000 & BufferGel trial CAPRISA 008 Tenofovir gel implementation trial FHI SAVVY trial MDP 0.5% PRO2000 trial IPM dapivarine ring 2% PRO2000 ‘90 ‘92 ’98 ’00 ‘03 ‘04 ‘04 ’05 ’05 ’07 ’09 ‘11 Safe but not effective Increased HIV infection Stopped for futility Effective Planned

  17. November 2010: Oral PrEP prevents HIV in MSM – iPrEx trial 131 infections after randomization 83 in placebo 48 in FTC/TDF • Primary HIV analysis (1 May): 44% protection • At the end of the study: 42% (95% CI 18%-60%) • No effect on HSV-2 TDF-DP drug levels in blood << EC50 for HSV

  18. CAPRISA 004 and iPrEX trials are in Science’s Top 10 Scientific Breakthroughs in 2010

  19. May 2011: Proof that ART prevents HIV transmission from infected partners (HPTN 052) - 1763 discordant couples - 13 sites in Africa, America & Asia - ART at CD4 up to 550 vs only <250 - HIV incidence (placebo) = 2.2 per 100pys - 28 matched HIV infn: 27 in delayed ART - 96% effective (excl. non-matched viruses) - Trial halted early for effectiveness

  20. July 2011: Oral PrEP prevents HIV transmission in discordant couples (PartnersPrEP) • 4,758 HIV serodiscordant couples enrolled • Kenya and Uganda • Daily oral TDF or TDF/FTC or Placebo • HIV incidence (placebo group) = 1.9 per 100pys • 78 HIV infections after randomization • 18 in TDF arm (62% protection) • 13 in FTC/TDF arm (73% protection) • 47 Placebo

  21. July 2011: Oral PrEP prevents HIV in heterosexual men & women (Botswana TDF2) • 1219 heterosexual men & womenenrolled • Botswana • Daily oral TDF-FTC • HIV incidence rate (placebo) = 3.1 per 100pys • 33 HIV infections after randomization • 9 in FTC/TDF arm (63% protection) • 24 in Placebo

  22. Clinical trial evidence for preventing sexual HIV transmission – July 2010 Study Effect size (CI) Medical male circumcision (Orange Farm, Rakai, Kisumu) 54% (38; 66) STD treatment (Mwanza) 42% (21; 58) HIV Vaccine (Thai RV144) 31% (1; 51) 0% 10 20 30 40 50 60 70 80 90 100% Efficacy

  23. Clinical trial evidence for preventing sexual HIV transmission – July 2011 Study Effect size (CI) Treatment for prevention (Africa, Asia, America’s) 96% (73; 99) PrEP for discordant couples (Partners PrEP) 73% (49; 85) PrEP for heterosexuals (Botswana TDF2) 63% (21; 48) Medical male circumcision (Orange Farm, Rakai, Kisumu) 54% (38; 66) PrEP for MSMs (America’s, Thailand, South Africa) 44% (15; 63) STD treatment (Mwanza) 42% (21; 58) Microbicide (CAPRISA 004 tenofovir gel) 39% (6; 60) HIV Vaccine (Thai RV144) 31% (1; 51) 0% 10 20 30 40 50 60 70 80 90 100% Efficacy

  24. 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 Treatment for prevention Behavioural positive prevention Donnell D, Lancet 2010 Cohen M, NEJM 2011 Fisher J, JAIDS 2004 COMBINATION HIV PREVENTION Male Condoms HIV Counselling and Testing Oral pre-exposure prophylaxis Coates T, Lancet 2000 Grant R, NEJM 2010 (MSM) Baeten J , 2011 (Couples) Paxton L, 2011 (Heterosexuals) Behavioural Intervention Post Exposure prophylaxis (PEP) Vaccines • Abstinence • Be Faithful Scheckter M, 2002 Rerks-Ngarm S, NEJM 2009 Note: PMTCT, Screening transfusions, Harm reduction, Universal precautions, etc. have not been included – this is focused on reducing sexual transmission

  25. 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 Treatment for prevention Behavioural positive prevention Female Condoms Donnell D, Lancet 2010 Cohen M, NEJM 2011 Fisher J, JAIDS 2004 HIV PREVENTION FOR MSM Male Condoms HIV Counselling and Testing Oral pre-exposure prophylaxis Coates T, Lancet 2000 Grant R, NEJM 2010 (MSM) Baeten J , 2011 (Couples) Paxton L, 2011 (Heterosexuals) Behavioural Intervention Post Exposure prophylaxis (PEP) Vaccines • Abstinence • Be Faithful Scheckter M, 2002 Rerks-Ngarm S, NEJM 2009 Note: PMTCT, Screening transfusions, Harm reduction, Universal precautions, etc. have not been included – this is focused on reducing sexual transmission

  26. Limitations of current HIV prevention in Africa • MSM and their needs are largely ignored in HIV prevention and treatment efforts in Africa • Most AIDS prevention messages are targeted at heterosexual men and women emphasizing the risks of transmission through peno-vaginal sex and not through anal intercourse • The needs of the many women who are unable to get men to use condoms in anal sex are ignored • Hence the need for a rectal microbicide in Africa…

  27. WHO is preparing to develop guidelines for tenofovir gel implementation for women

  28. Conclusion • HIV spreading in MSM AND heterosexuals in Africa • Unprotected anal sex is a key HIV risk factor • Current HIV prevention efforts are unable to contain or reduce the spread of HIV infection thro anal sex • Combating HIV is not only about scaling-up proven prevention – but also new prevention technologies • A rectal microbicide, as a new HIV prevention technology is urgently needed in Africa for the large number of people practicing anal sex, ie: • Men who have Sex with Men • Bisexual men • Women

More Related