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Life Guide U.S. essentials
English

If you are a man who has sex with men and has high-risk sex, ask a designated HIV hospital about pre-exposure prophylaxis; taken on schedule, it cuts infections by more than 70%

  • Moderate value
  • Evidence A
  • Buys life
  • Costs a lot
  • Takes some hours
  • Some willpower

In plain words

People who are not yet infected take an antiviral drug in advance, called pre-exposure prophylaxis. For those who take it on schedule, the risk of infection falls by more than 70%. For those who take it on and off, it does almost nothing. It is a prescription drug: you first get checked at a hospital, then it is prescribed, then you return for regular checkups.

Cost

It is a prescription drug, paid out of pocket in most places, at a price from a few hundred to a few thousand CNY. Before it is prescribed you need tests for HIV, kidney function and hepatitis B. After that, a recheck every 3 months. The hard part is taking it on time every day.

What you get

The drug is a combination tablet of emtricitabine and tenofovir. The iPrEx trial had 2499 men who have sex with men and transgender women take the drug or a placebo every day. The drug group had 44% fewer infections (95% CI 15–63). Among people with measurable drug in the blood, the protection was far stronger. The U.K. PROUD trial had 544 men who have sex with men. The group that started the drug immediately had 86% fewer infections than the group that waited a year (90% CI 64–96, a 90% plausible range). The French IPERGAY trial, with drug taken on demand around sex, found 86% fewer infections (95% CI 40–98). A meta-analysis used by the World Health Organization pooled the trials. Overall RR was 0.49 (0.33–0.73, about 51% lower). In trials where more than 70% took the drug, RR was 0.30 (0.21–0.45, about 70% lower). In those where fewer than 40% did, RR was 0.95, essentially no effect. In August 2020 the National Medical Products Administration (国家药监局) approved this drug for pre-exposure prophylaxis. Adults and adolescents weighing at least 35 kg can use it (multiple countries / China).

Notes

The people in the trials were mainly men who have sex with men, so they are the group who should ask first. Others who have high-risk sex can also ask a doctor whether it suits them. Before the drug is prescribed, you must first confirm you are not infected; in someone already infected, taking it can make the virus drug-resistant, and a home test strip result can't be relied on. People with hepatitis B can have a flare of hepatitis when they stop, which is why it is tested for before prescribing. The World Health Organization recommends on-demand dosing only for men who have sex with men, suited to people who average fewer than 2 times a week. The way to take it is 2 tablets 2 to 24 hours before sex, then 1 tablet at 24 hours and 1 at 48 hours. Women and people with hepatitis B can only take it every day. In the on-demand trials, the drug group had more stomach and kidney side effects than the placebo group, so checkups can't be skipped. In China, pilot programs began in 2019 among men who have sex with men, and a 2024 plan says to “implement it in a standardized way.” No nationwide free policy was found. Get it at the infectious disease department or STI/AIDS clinic of the local designated AIDS hospital, and first call the local CDC to ask which hospital can prescribe it. It does not protect against syphilis, gonorrhea and other infections, so condoms are still needed; see §1.30 (use a condom for the whole of every sexual act). If a high-risk act has already happened, for the remedy see §13.38 (get blocking medicine within 72 hours). The beneficiary is mainly you, and it also protects your partner.

Evidence grade
A : Specific numbers from meta-analyses, large cohorts or randomized trials; for law and policy, the statute or official text.
Sources
  1. Grant RM, Lama JR, Anderson PL, et al. (2010). Preexposure chemoprophylaxis for HIV prevention in men who have sex with men. New England Journal of Medicine, 363(27), 2587–2599. https://doi.org/10.1056/NEJMoa1011205
  2. McCormack S, Dunn DT, Desai M, et al. (2016). 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. The Lancet, 387(10013), 53–60. https://doi.org/10.1016/S0140-6736(15)00056-2
  3. Molina JM, Capitant C, Spire B, et al. (2015). On-demand preexposure prophylaxis in men at high risk for HIV-1 infection. New England Journal of Medicine, 373(23), 2237–2246. https://doi.org/10.1056/NEJMoa1506273
  4. Fonner VA, Dalglish SL, Kennedy CE, et al. (2016). Effectiveness and safety of oral HIV preexposure prophylaxis for all populations. AIDS, 30(12), 1973–1983. https://doi.org/10.1097/QAD.0000000000001145
  5. Xu JJ, Huang XJ, Liu XC, et al. (2020). Consensus statement on human immunodeficiency virus pre-exposure prophylaxis in China. Chinese Medical Journal, 133(23), 2840–2846. https://doi.org/10.1097/CM9.0000000000001181（中文版《中国 HIV 暴露前预防用药专家共识》）
  6. World Health Organization (2019). What's the 2+1+1? Event-driven oral pre-exposure prophylaxis to prevent HIV for men who have sex with men (WHO/CDS/HIV/19.8). https://www.who.int/publications/i/item/what-s-the-2-1-1-event-driven-oral-pre-exposure-prophylaxis-to-prevent-hiv-for-men-who-have-sex-with-men
  7. 国务院办公厅 (2024). 中国遏制与防治艾滋病规划（2024—2030 年）. https://www.gov.cn/zhengce/zhengceku/202412/content_6992033.htm

Translated from the Chinese original. Original book, section 1, tip 38. This section is about health and medicines. It is general information, not a substitute for a doctor’s diagnosis or prescription. Content may be out of date and rules differ by place. When you actually deal with an agency, a doctor or a court, follow what local officials, doctors and lawyers tell you. Disclaimer