Archive | March, 2017

Over 22,000 Participants Enrolled in PrEP Trials

24 Mar

Overview of eleven different PrEP Trials divided into treatment arms. Trials are organized by total number of participants.

Link to Larger Figure

Pre-Exposure Prophylaxis, or PrEP, is a medication that prevents HIV infection. It is intended to be used together with safer sex practices (e.g., condoms). This stacked barplot shows the number of participants in 11 different PrEP studies. The earliest study in the plot is the West Africa trial, which was initiated in 2004. Each bar corresponds to its labeled trial. The different colored sections in each bar represent the “arms” or “cohorts” of the study. Most studies have a placebo cohort and a treatment cohort. The PROUD study only has the treatment arm. The VOICE┬ástudy has three different treatment arms, while the Partners PrEP study has two different treatment arms.

The light blue color represents the Truvada (emtricitabine/tenfovir disoproxil fumarate combination) cohorts. The dark blue color represents the cohort only given TDF (tenofovir disoproxil fumarate), and the off-white color represents the placebo cohort. The light green and pink colors represent the 1% Tenofovir vaginal gel cohort and placebo vaginal gel cohorts, respectively. The blue pill icon over a graph indicates the study employed a daily oral pill to be used as PrEP. The green gel icon indicates the study employed a topical vaginal gel to be used as PreP. We can see that all of the individuals enrolled in the studies give a combined total of over 22,000 participants. Even though PrEP is a relatively new preventative, the plot shows that a large number of participants have already enrolled in PrEP trials and the prophylaxis is becoming well studied.

About the Author

Dwayne Evans is a graduate student at SFSU. He works on HIV drug resistance in relation to Pre-Exposure Prophylaxis (PrEP). He made a figure to show how many people participated in PrEP trials since 2004.


Dwayne Evans, SFSU


(Please click on the reference for a link to the study)


Marrazzo JM, Ramjee G, Chirenje ZM, et al. Tenofovir-Based Preexposure Prophylaxis for HIV Infection among African Women. N Engl J Med 2015; 372:509-518.

Partners PrEP Study

Baeten JM, Donnell D, Celum C, et al. Antiretroviral Prophylaxis for HIV Prevention in Heterosexual Men and Women. N Engl J Med 2012; 367:399-410

Donnell D, Baeten JM, Celum C, et al. HIV Protective Efficacy and Correlates of Tenofovir Blood Concentrations in a Clinical Trial of PrEP for HIV Prevention. J Acquir Immune Defic Syndr 2014; 66: 340-348

Ndase P, Celum C, Baeten JM, et al. Successful discontinuation of the placebo arm and provision of an effective HIV prevention product after a positive interim efficacy result: the partners PrEP study experience. J Acquir Immune Defic Syndr 2014; 66:206-12

iPrEx Study

Grant RM, Lama JR, Glidden DV, et al. Preexposure Chemoprophylaxis for HIV Prevention in Men Who Have Sex with Men. N Engl J Med 2010; 363:2587-99

Liegler T, Abdel-Mohsen M, Grant RM, et al. HIV-1 Drug Resistance in the iPrEx Preexposure Prophylaxis Trial. J Infect Dis 2014; 210:1217-27

Bangkok Tenofovir Study

Choopanya K, Martin M, Vanichseni S, et al. Antiretroviral prophylaxis for HIV infection in injecting drug users in Bangkok, Thailand (the Bangkok Tenofovir Study): a randomized, double-blind, placebo-controlled phase 3 trial. The Lancet 2013; 381:2083-90


Van Damme L, Corneli A, Taylor D, et al. Preexposure Prophylaxis for HIV Infection among African Women. N Engl J Med 2012; 367:411-422

TDF2 Study

Thigpen MC, Kebaabetswe PM, Brooks JT, et al. Antiretroviral Preexposure Prohpylaxis for Heterosexual HIV Transmission in Botswana. N Engl J Med 2012; 367:423-434

Chirwa LI, Johnson JA, Brooks JT, et al. CD4(+) cell count, viral load, and drug resistance patterns among heterosexual breakthrough HIV infections in a study of oral preexposure prophylaxis. AIDS 2014;28:223-6

West Africa Study

Peterson L, Taylor D, Cates W, et al. Tenofovir Disoproxil Fumarate for Prevention of HIV Infection in Women: A Phase 2, Double-Blind, Randomized, Placebo-Controlled Trial. PLoS Clin Trials 2007; 2:e27

CAPRISA 004 Trial

Mansoor LE, Abdool Karim Q, Yende-Zuma N, et al. Adherence in the CAPRISA 004 Tenofovir Gel Microbicide Trial. AIDS Behav 2014; 18:811


McCormack S, Dunn DT, Gill ON, et al. Pre-exposure prophylaxis to prevent the acquisition of HIV-1 infection (PROUD): effectiveness results from the pilot phase of a pragmatic open-label randomized trial. The Lancet 2015; 387:53-60


Molina JM, Capitant C, Delfraissy JF, et al. On Demand Preexposure Prophylaxis in Men at High Risk for HIV-1 Infection. N Engl J Med 2015;373:2237-2246

US MSM Trial

Liu A, Vittinghoff E, Buchbinder S, et al. Sexual risk behavior among HIV-uninfected men who have sex with men (MSM) participating in a tenofovir pre-exposure prophylaxis (PrEP) randomized trial in the United States. J Acquir Immune Defic Syndr 2013; 64:87-94