Human Immunodeficiency Virus Seroconversion Among Men Who Have Sex With Men Who Use Event-Driven or Daily Oral Pre-Exposure Prophylaxis (CohMSM-PrEP): A Multi-Country Demonstration Study From West Africa
Authors: Laurent Christian , Yaya Issifou , Cuer Benjamin , Sagaon-Teyssier Luis , Mensah Ephrem , Dah Ter Tiero Elias , Coulibaly Alou , Kouamé Malan Jean-Baptiste , Peytavin Gilles , Serrano Laetitia , Eubanks August , Traoré Issa , Diallo Fodié , Riegel Lucas , Rojas Castro Daniela , Dagnra Claver A , Anoma Camille , Vuylsteke Bea , Dembélé Keita Bintou , Spire Bruno ,   CohMSM-PrEP Study Group, Laurent Christian , Yaya Issifou , Ouedraogo Sayouba , Granouillac Bruno , Cuer Benjamin , Serrano Laetitia , Peeters Martine , Couderc Clotilde , Spire Bruno , Sagaon-Teyssier Luis , Mora Marion , Maradan Gwenaëlle , Bourrelly Michel , Berenger Cyril , Boyer Sylvie , Castro Daniela Rojas , Riegel Lucas , Palvadeau Paméla , Vuylsteke Bea , Baetselier Irith De , Reyniers Thijs , Keita Bintou Dembélé , Diallo Fodié , Coulibaly Alou , Maïga Alassane Kader , Camara Drissa , Diarra Mahamadou , Ouologuem Aly , Sangaré Naboh , Keita Abdoul Aziz , Cissé Oumar , Traoré Fodé , Ouary Bréhima Abdrahamane , Kanta Ibrahima , Coulibaly Bakary , Anoma Camille , Kouamé Malan Jean-Baptiste , Kotchi Rachelle , Aka Niamkey Thomas , Lokrou Kpassou Julien , Coulibaly Noufo Hamed , Koffi Ekessi Jean Armel , N’guessan Dibi Frédéric , Yoro Stéphane-Alain Babo , Cissé Adama , Dah Ter Tiero Elias , Traoré Issa , Rajaonarivelo Camille , Ouedraogo Fayçal Rodrique , Ouedraogo Joseph , Coulibaly Christian , Ouedraogo Mamadou , Ilboudo Ousseni , Traoré Abdoulazziz , Comsiambo Honoré , Mensah Ephrem , Agboyibor Mawuényégan Kouamivi , Attisso Anani , Kokouba Anouwarsadat , Badjassim Aléda Mawuli , Agbomadji Kouakou Kokouvi Selom , Attiogbe Messan , Yaka Kossi Jeff , Ekon Agbégnigan Lorette , Bimba Julien , Dagnra Claver Anoumou , Tegueni Kokou Dominique 
Published: April 2023

Abstract

Background
Data on human immunodeficiency virus (HIV) seroconversion among men who have sex with men (MSM) using pre-exposure prophylaxis (PrEP) in West Africa are needed. This study aimed to document HIV seroconversion and associated determinants, PrEP adherence, plasma drug concentrations, and HIV drug resistance in MSM using event-driven or daily PrEP in Burkina Faso, Côte d’Ivoire, Mali, and Togo.

Methods
A prospective cohort study was conducted in 2017–2021 among HIV-seronegative MSM aged 18 or over who were at high risk of HIV infection. Participants could choose between event-driven and daily PrEP, switch regimens, and discontinue or restart PrEP. The determinants of HIV incidence were investigated using a multivariate mixed-effects Poisson regression analysis.

Results
A total of 647 participants were followed for a total time of 1229.3 person-years. Of 5371 visits, event-driven PrEP was chosen in 3873 (72.1%), and daily PrEP in 1400 (26.1%). HIV incidence was 2.4 per 100 person-years (95% confidence interval [CI] 1.5–3.6) for event-driven PrEP, and 0.6 per 100 person-years (95% CI .1–2.3) for daily PrEP (adjusted incidence rate ratio 4.40, 95% CI 1.00–19.36, P = .050). Adequate adherence was lower with event-driven than daily PrEP (44.3% vs 74.9%, P &lt; .001). Plasma drug concentrations were undetectable in 92 (97.9%) of the 94 measures taken for 23 participants who seroconverted. Only 1 participant had resistance to PrEP drugs.

Conclusions
HIV seroconversions mainly occurred in participants who chose event-driven PrEP. The study's data highlighted major difficulties with adherence to this regimen. Improving adherence to event-driven PrEP constitutes a major research and public health priority in this context.