Viral suppression and HIV transmission in serodiscordant male couples: an international, prospective, observational, cohort study

Benjamin R Bavinton; Angie N Pinto; Nittaya Phanuphak; Beatriz Grinsztejn; Garrett P Prestage; Iryna B Zablotska-Manos; Fengyi Jin; Christopher K Fairley; Richard Moore; Norman Roth; Mark Bloch; Catherine Pell; Anna M McNulty; David Baker; Jennifer Hoy; Ban Kiem Tee; David J Templeton; David A Cooper; Sean Emery; Anthony Kelleher; Andrew E Grulich; Opposites Attract Study Group

doi:10.1016/S2352-3018(18)30132-2

Viral suppression and HIV transmission in serodiscordant male couples: an international, prospective, observational, cohort study

Lancet HIV. 2018 Aug;5(8):e438-e447. doi: 10.1016/S2352-3018(18)30132-2. Epub 2018 Jul 17.

Authors

Benjamin R Bavinton¹, Angie N Pinto², Nittaya Phanuphak³, Beatriz Grinsztejn⁴, Garrett P Prestage², Iryna B Zablotska-Manos⁵, Fengyi Jin², Christopher K Fairley⁶, Richard Moore⁷, Norman Roth⁸, Mark Bloch⁹, Catherine Pell¹⁰, Anna M McNulty¹¹, David Baker¹², Jennifer Hoy¹³, Ban Kiem Tee¹⁴, David J Templeton¹⁵, David A Cooper¹⁶, Sean Emery¹⁷, Anthony Kelleher², Andrew E Grulich²; Opposites Attract Study Group

Collaborators

Affiliations

¹ The Kirby Institute, Sydney, NSW, Australia. Electronic address: bbavinton@kirby.unsw.edu.au.
² The Kirby Institute, Sydney, NSW, Australia.
³ PREVENTION, Thai Red Cross AIDS Research Centre, Bangkok, Thailand.
⁴ Evandro Chagas Institute of Clinical Research, FIOCRUZ, Rio de Janeiro, Brazil.
⁵ Sydney Medical School-Westmead, University of Sydney, Sydney, NSW, Australia.
⁶ Monash University, Melbourne, VIC, Australia; Melbourne Sexual Health Centre, Melbourne, VIC, Australia.
⁷ Northside Clinic, Melbourne, VIC, Australia; The Alfred Hospital, Melbourne, VIC, Australia.
⁸ Prahran Market Clinic, Melbourne, VIC, Australia.
⁹ Holdsworth House Medical Practice, Sydney, NSW, Australia.
¹⁰ Taylor Square Private Clinic, Sydney, NSW, Australia.
¹¹ University of New South Wales, Sydney, NSW, Australia; Sydney Sexual Health Centre, Sydney, NSW, Australia.
¹² East Sydney Doctors, Sydney, NSW, Australia.
¹³ Monash University, Melbourne, VIC, Australia; The Alfred Hospital, Melbourne, VIC, Australia.
¹⁴ Centre Clinic, Melbourne, VIC, Australia.
¹⁵ The Kirby Institute, Sydney, NSW, Australia; Sydney Medical School, University of Sydney, Sydney, NSW, Australia; RPA Sexual Health, Sydney, NSW, Australia.
¹⁶ The Kirby Institute, Sydney, NSW, Australia; Immunology B Ambulatory Clinic, St Vincent's Hospital, Sydney, NSW, Australia.
¹⁷ The Kirby Institute, Sydney, NSW, Australia; Faculty of Medicine, University of Queensland, Brisbane, QLD, Australia.

PMID: 30025681
DOI: 10.1016/S2352-3018(18)30132-2

Abstract

Background: Evidence on viral load and HIV transmission risk in HIV-serodiscordant male homosexual couples is limited to one published study. We calculated transmission rates in couples reporting condomless anal intercourse (CLAI), when HIV-positive partners were virally suppressed, and daily pre-exposure prophylaxis (PrEP) was not used by HIV-negative partners.

Methods: In the Opposites Attract observational cohort study, serodiscordant male homosexual couples were recruited from 13 clinics in Australia, one in Brazil, and one in Thailand. At study visits, HIV-negative partners provided information on sexual behaviour and were tested for HIV and sexually transmitted infections; HIV-positive partners had HIV viral load tests, CD4 cell count, and sexually transmitted infection tests done. Viral suppression was defined as less than 200 copies per mL. Linked within-couple HIV transmissions were identified with phylogenetic analysis. Incidence was calculated per couple-year of follow-up, focusing on periods with CLAI, no use of daily PrEP, and viral suppression. One-sided upper 95% CI limits for HIV transmission rates were calculated with exact Poisson methods.

Findings: From May 8, 2012, to March 31, 2016, in Australia, and May 7, 2014, to March 31, 2016, in Brazil and Thailand, 358 couples were enrolled. 343 couples had at least one follow-up visit and were followed up for 588·4 couple-years. 258 (75%) of 343 HIV-positive partners had viral loads consistently less than 200 copies per mL and 115 (34%) of 343 HIV-negative partners used daily PrEP during follow-up. 253 (74%) of 343 couples reported within-couple CLAI during follow-up, with a total of 16 800 CLAI acts. Three new HIV infections occurred but none were phylogenetically linked. There were 232·2 couple-years of follow-up and 12 447 CLAI acts in periods when CLAI was reported, HIV-positive partners were virally suppressed, and HIV-negative partners did not use daily PrEP, resulting in an upper CI limit of 1·59 per 100 couple-years of follow-up for transmission rate.

Interpretation: HIV treatment as prevention is effective in men who have sex with men. Increasing HIV testing and linking to immediate treatment is an important strategy in HIV prevention in homosexual men.

Funding: National Health and Medical Research Council; amfAR, The Foundation for AIDS Research; ViiV Healthcare; and Gilead Sciences.

Publication types

Multicenter Study
Observational Study
Research Support, Non-U.S. Gov't

MeSH terms

Adult
Anti-HIV Agents / therapeutic use
Australia
Brazil
CD4 Lymphocyte Count
Condoms
HIV / genetics
HIV Infections / drug therapy
HIV Infections / prevention & control*
HIV Infections / transmission*
Homosexuality, Male
Humans
Male
Middle Aged
Phylogeny
Pre-Exposure Prophylaxis
Prospective Studies
Sexual Behavior
Sexual and Gender Minorities
Thailand
Viral Load*

Substances

Anti-HIV Agents