Sexual Activity Without Condoms and Risk of HIV Transmission in Serodifferent Couples When the HIV-Positive Partner Is Using Suppressive Antiretroviral Therapy.

TitleSexual Activity Without Condoms and Risk of HIV Transmission in Serodifferent Couples When the HIV-Positive Partner Is Using Suppressive Antiretroviral Therapy.
Publication TypeJournal Article
Year of Publication2016
AuthorsRodger AJ, Cambiano V, Bruun T, Vernazza P, Collins S, Van Lunzen J, Corbelli GMaria, Estrada V, Geretti AMaria, Beloukas A, Asboe D, Viciana P, Gutiérrez F, Clotet B, Pradier C, Gerstoft J, Weber R, Westling K, Wandeler G, Prins JM, Rieger A, Stoeckle M, Kümmerle T, Bini T, Ammassari A, Gilson R, Krznaric I, Ristola M, Zangerle R, Handberg P, Antela A, Allan S, Phillips AN, Lundgren J
Corporate AuthorsPARTNER study group
JournalJAMA
Volume316
Issue2
Pagination171-81
Date Published2016 Jul 12
ISSN1538-3598
KeywordsAdult, Anti-HIV Agents, Condoms, Europe, Family Characteristics, Female, HIV Infections, HIV Seronegativity, HIV Seropositivity, HIV-1, Humans, Male, Middle Aged, Phylogeny, Prospective Studies, Risk, RNA, Viral, Sexual Behavior, Sexual Partners, Unsafe Sex, Viral Load
Abstract

IMPORTANCE: A key factor in assessing the effectiveness and cost-effectiveness of antiretroviral therapy (ART) as a prevention strategy is the absolute risk of HIV transmission through condomless sex with suppressed HIV-1 RNA viral load for both anal and vaginal sex.

OBJECTIVE: To evaluate the rate of within-couple HIV transmission (heterosexual and men who have sex with men [MSM]) during periods of sex without condoms and when the HIV-positive partner had HIV-1 RNA load less than 200 copies/mL.

DESIGN, SETTING, AND PARTICIPANTS: The prospective, observational PARTNER (Partners of People on ART-A New Evaluation of the Risks) study was conducted at 75 clinical sites in 14 European countries and enrolled 1166 HIV serodifferent couples (HIV-positive partner taking suppressive ART) who reported condomless sex (September 2010 to May 2014). Eligibility criteria for inclusion of couple-years of follow-up were condomless sex and HIV-1 RNA load less than 200 copies/mL. Anonymized phylogenetic analysis compared couples' HIV-1 polymerase and envelope sequences if an HIV-negative partner became infected to determine phylogenetically linked transmissions.

EXPOSURES: Condomless sexual activity with an HIV-positive partner taking virally suppressive ART.

MAIN OUTCOMES AND MEASURES: Risk of within-couple HIV transmission to the HIV-negative partner.

RESULTS: Among 1166 enrolled couples, 888 (mean age, 42 years [IQR, 35-48]; 548 heterosexual [61.7%] and 340 MSM [38.3%]) provided 1238 eligible couple-years of follow-up (median follow-up, 1.3 years [IQR, 0.8-2.0]). At baseline, couples reported condomless sex for a median of 2 years (IQR, 0.5-6.3). Condomless sex with other partners was reported by 108 HIV-negative MSM (33%) and 21 heterosexuals (4%). During follow-up, couples reported condomless sex a median of 37 times per year (IQR, 15-71), with MSM couples reporting approximately 22,000 condomless sex acts and heterosexuals approximately 36,000. Although 11 HIV-negative partners became HIV-positive (10 MSM; 1 heterosexual; 8 reported condomless sex with other partners), no phylogenetically linked transmissions occurred over eligible couple-years of follow-up, giving a rate of within-couple HIV transmission of zero, with an upper 95% confidence limit of 0.30/100 couple-years of follow-up. The upper 95% confidence limit for condomless anal sex was 0.71 per 100 couple-years of follow-up.

CONCLUSIONS AND RELEVANCE: Among serodifferent heterosexual and MSM couples in which the HIV-positive partner was using suppressive ART and who reported condomless sex, during median follow-up of 1.3 years per couple, there were no documented cases of within-couple HIV transmission (upper 95% confidence limit, 0.30/100 couple-years of follow-up). Additional longer-term follow-up is necessary to provide more precise estimates of risk.

DOI10.1001/jama.2016.5148
Alternate JournalJAMA
PubMed ID27404185