1. Grant RM, Lama JR, Anderson PL, et al; iPrEx Study Team. Preexposure chemoprophylaxis for HIV prevention in men who have sex with men. N Engl J Med 2010;363:2587-99.

  1. McCormack S, Dunn DT, Desai M, 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 randomised trial. Lancet 2016;387:53-60.

  1. Thigpen MC, Kebaabetswe PM, Paxton LA, et al. Antiretroviral preexposure prophylaxis for heterosexual HIV transmission in Botswana. N Engl J Med 2012;367:423–34.

  1. Deutsch MB, Glidden DV, Sevelius J, et al; iPrEx investigators. HIV pre-exposure prophylaxis in transgender women: a subgroup analysis of the iPrEx trial. Lancet HIV 2015;2:e512–9.

  1. Choopanya K, Martin M, Suntharasamai P, et al; Bangkok Tenofovir Study Group. Antiretroviral prophylaxis for HIV infection in injecting drug users in Bangkok, Thailand (the Bangkok Tenofovir study): a randomised, double-blind, placebo-controlled phase 3 trial. Lancet 2013;381:2083–90.

  1. World Health Organization. Technical brief. What's the 2+1+1? Event-driven oral pre-exposure prophylaxis to prevent HIV for men who have sex with men: update to WHO’s recommendation on oral PrEP. July 2019. Available at: (last accessed 3 September 2019).

  1. Hosek SG, Rudy B, Landovitz R, et al; Adolescent Trials Network (ATN) for HIVAIDS Interventions. An HIV preexposure prophylaxis demonstration project and safety study for young MSM. J Acquir Immune Defic Syndr 2017;74:21-9.

  1. Hosek SG, Landovitz RJ, Kapogiannis B, et al. Safety and feasibility of antiretroviral preexposure prophylaxis for adolescent men who have sex with men aged 15 to 17 years in the United States. JAMA Pediatr 2017;171:1063-71.

  1. Noret M, Balavoine S, Pintado C, et al. Daily or on-demand oral tenofovir disoproxil fumarate/emtricitabine for HIV pre-exposure prophylaxis: experience from a hospital-based clinic in France. AIDS 2018;32:2161–9.

  1. Molina JM, Charreau I, Spire B, et al; ANRS IPERGAY Study Group. Efficacy, safety, and effect on sexual behaviour of on-demand pre-exposure prophylaxis for HIV in men who have sex with men: an observational cohort study. Lancet HIV 2017;4:e402–10.

  1. Molina JM, Ghosn J, Algarte‐Génin M, et al; ANRS Study Group. Incidence of HIV‐infection with daily or on‐demand PrEP with TDF/FTC in Paris area. Update from the ANRS Prévenir Study. Abstract TUAC0202. Oral abstracts of the 10th IAS Conference on HIV Science, 21-24 July 2019, Mexico City, Mexico. J Int AIDS Soc 2019;22 Suppl 5:e25327.

  1. Molina JM, Capitant C, Spire B, et al; ANRS IPERGAY Study Group. On-demand preexposure prophylaxis in men at high risk for HIV-1 infection. N Engl J Med 2015;373:2237-46.

  1. Antoni G, Tremblay C, Charreau I, et al. On-demand PrEP with TDF/FTC remains highly effective among MSM with infrequent sexual intercourse: a sub-study of the ANRS IPERGAY trial. Abstract TUAC0102. International AIDS Society (IAS) Conference on HIV Science. July 2017; Paris, France.

  1. Liegeon G, Antoni G, Pialoux G, et al. Changes in kidney function among MSM initiation on-demand TDF/FTC for HIV PrEP. Abstract Number: 960. Conference on Retroviruses and Opportunistic Infections (CROI); 4-7 March 2019; Seattle, Washington.

  1. Grant RM, Mannheimer S, Hughes JP, et al. Daily and nondaily oral preexposure prophylaxis in men and transgender women who have sex with men: The Human Immunodeficiency Virus Prevention Trials Network 067/ADAPT Study. Clin Infect Dis 2018;66:1712–21.

  1. PrEP in Europe [website]. Intermittent PrEP. Available at: (last accessed 3 September 2019).

  1. Vaccher SJ, Gianacas C, Templeton DJ, et al; PRELUDE Study Team. Baseline preferences for daily, event-driven, or periodic HIV pre-exposure prophylaxis among gay and bisexual men in the PRELUDE Demonstration Project. Front Public Health 2017;5:341.

  1. Cornelisse VJ, Lal L, Price B, et al. Interest in switching to on-demand pre-exposure prophylaxis (PrEP) among Australian users of daily PrEP: an online survey. Open Forum Infect Dis 2019;6:ofz287.

  1. Fonner VA, Dalglish SL, Kennedy CE, et al. Effectiveness and safety of oral HIV preexposure prophylaxis for all populations. AIDS 2016;30:1973–83.

  1. Buttram ME, Kurtz SP. Preliminary evidence of HIV seroconversion among HIV-negative men who have sex with men taking non-prescribed antiretroviral medication for HIV prevention in Miami, Florida, USA. Sex Health 2017;14:193-5.

  1. Gilead Sciences. Full prescribing information. Issued June 2013. Available at: (last accessed 4 September 2019).

  1. Panel on Antiretroviral Guidelines for Adults and Adolescents. Guidelines for the use of antiretroviral agents in adults and adolescents with HIV. Department of Health and Human Services. Last updated 10 July 2019. Available at: (last accessed 4 September 2019).

  1. Grant RM, Anderson PL, McMahan V, et al. Uptake of pre-exposure prophylaxis, sexual practices, and HIV incidence in men and transgender women who have sex with men: a cohort study. Lancet Infect Dis 2014;14:820–9.

  1. Patterson KB, Prince HA, Kraft E, et al. Penetration of tenofovir and emtricitabine in mucosal tissues: implications for prevention of HIV-1 transmission. Sci Transl Med 2011;3:112re4.

  1. Anderson PL. Pharmacology considerations for HIV prevention [presentation]. 13th International Workshop on Clinical Pharmacology of HIV. Barcelona, Spain; April 2012. Available at: (last accessed 4 September 2019).

  1. Anderson PL, Kiser JJ, Gardner EM, et al. Pharmacological considerations for tenofovir and emtricitabine to prevent HIV infection. J Antimicrob Chemother 2011;66:240-50.

  1. Cottrell ML, Yang KH, Prince HM, et al. A translational pharmacology approach to predicting outcomes of preexposure prophylaxis against HIV in men and women using tenofovir disoproxil fumarate with or without emtricitabine. J Infect Dis 2016;214:55-64.

  1. Cottrell L, Yang KH, Prince HMA, et al; A Translational Pharmacology Approach to Predicting Outcomes of Preexposure Prophylaxis Against HIV in Men and Women Using Tenofovir Disoproxil Fumarate With or Without Emtricitabine. The Journal of Infectious Diseases 2016;214:55–64

  1. Glidden DV, Anderson PL, Grant RM. Pharmacology supports “on-demand” PrEP. Lancet HIV. 2016: 3(9):e405-e406

  1. Cornelisse VJ, Wright EJ, Fairley CK, McGuinness SL. Sexual safety and HIV prevention in travel medicine: Practical considerations and new approaches. Travel Med Infect Dis 2019;28:68-73.

  1. Seifert SM, Glidden DV, Meditz AL, et al. Dose response for starting and stopping HIV preexposure prophylaxis for men who have sex with men. Clin Infect Dis 2015;60:804-10.