About Oral PrEP
Oral PrEP works if you take it.
Across populations, geography and route of exposure the data all point in the same direction—TDF/FTC (brand name Truvada) works to prevent HIV. Studies demonstrate that daily use of the drug provides protection for all populations, and for cisgender men who have sex with men, an event-driven approach to dosing is also effective (taking a double dose of TDF/FTC between 2 and 24 hours before having sex and then, if sex occurs, one pill 24 hours after the double dose and another 24 hours later).
In October 2019, the US Food and Drug Administration (FDA) approved F/TAF (brand name Descovy) as daily oral PrEP for HIV prevention in men who have sex with men and transgender women. Due to lack of data on safety and efficacy, F/TAF is not approved for use by cisgender women. The drug manufacturer Gilead is designing a new trial to gather data on the efficacy of F/TAF in cisgender women, the results of which are expected in 2022.
Both TDF/FTC and F/TAF are safe for PrEP.
There were no major adverse events observed in any of the trials. Some mild side effects were reported, the majority of which went away over time. With respect to F/TAF however, additional safety data still needs to be collected in the upcoming trial in cisgender women, as well as additional studies that will examine the effects of long-term use of the drug.
Other tenofovir-based oral PrEP options, such as TDF and TDF/3TC have also been proven safe and effective at preventing HIV, and are available in certain countries as generic options.
Effective use is essential.
Each of the trials that found a benefit from taking oral PrEP also found that people who had high levels of adherence to the drug had high levels of protection. Lower adherence was associated with low or no protection. Effective use of PrEP means taking PrEP consistently when engaging in risky behavior (such as unprotected sex or sharing needles). Periods of risk will vary based on a person’s life circumstances, but as long PrEP is taken as prescribed during these periods, it will offer protection.
Oral PrEP options exist for all populations.
TDF/FTC oral PrEP is highly protective in both cisgender and transgender men and women. It takes longer to establish protection in vaginal tissue than in colorectal tissue, and both cisgender and transgender women need to be adherent to daily regimens. But when people take it as prescribed, they are protected.
F/TAF is equally as effective as TDF/FTC for men who have sex with men and transgender women, although we do not yet know if it is effective for cisgender women.
PrEP: An introductory factsheet
People who can benefit most from oral PrEP can — and do — take it, but program design matters, a lot.
Early implementation projects showed that individuals with high HIV risk could also be highly adherent to oral PrEP. As PrEP moves into large-scale, national programs, it is clear that effective use depends on providers, peers, communities and potential users having access to and engaging with programs that are centered on the needs of those who need PrEP most.
Understanding the social and behavioral factors influencing the decisions of those in need of HIV prevention options is critical. For example, the Prevention Market Manager (a collaboration between AVAC and the Clinton Health Access Initiative) is conducting an end user research in South Africa focused on understanding how best to reach adolescent girls and young women with HIV prevention products and programs. To date, the project has revealed that young women care primarily about the preservation and management of sexual relationships, but not explicitly about HIV prevention. Current HIV prevention methods often conflict with relationship goals, making HIV prevention uptake and adherence challenging.
Ultimately, in order to improve access to products and increase the impact of biomedical HIV prevention, it is critical to design services which address the needs of at-risk individuals. Strategies for differentiated service delivery in-country, such as the integrating PrEP provision with sexual and reproductive health services, can increase uptake of prevention and improve adherence.
Resistance is rare.
Individual cases of HIV drug resistance have been observed in trials and implementation projects to date. The documented cases of resistance appear to have occurred in participants who were already HIV-positive when they began taking oral PrEP, but still in the “window period” of early infection when detection is more difficult. These individuals tested HIV-negative on screening tests. This reinforces the importance of regular testing for anyone initiating or taking oral PrEP. There are few cases of individuals who took TDF/FTC as PrEP, were exposed to virus resistant to both TDF and FTC, and became infected while taking PrEP. Transmission of multi-drug resistant strains is rare and widespread PrEP failure due to drug-resistant virus is highly unlikely.
Daily oral PrEP doesn’t protect against other STIs.
Oral PrEP is a terrific HIV prevention tool. It doesn’t reduce risk of chlamydia, gonorrhea, syphilis or herpes. Male and female condoms do. Comprehensive access to PrEP, condoms, Voluntary Medical Male Circumcision, voluntary medical male circumcision (VMMC), communication and counseling makes prevention work for all.