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DISCOVER Trial Factsheet

About the DISCOVER Trial:
Gilead Sciences is conducting a clinical trial at 92 study sites across the United States, Canada and Western Europe. The purpose of the trial is to assess whether F/TAF (trade name Descovy) is safe and effective as an oral daily HIV pre-exposure prophylaxis (PrEP) product. It is being compared with F/TDF (trade name Truvada), which is approved for use as PrEP in many countries and has already been proven safe and highly effective at reducing HIV acquisition.

This study is enrolling 5,000 cisgender men and transgender women who have sex with men. Participants will be randomized to receive either Truvada plus a placebo pill that looks exactly like Descovy or Descovy plus a placebo pill that looks exactly like Truvada. In other words, all participants will receive two pills to take each day: one, a placebo pill, and the other, either Truvada or Descovy. However, neither participants nor researchers will know whether they are getting the approved PrEP drug product (Truvada) or the one being tested (Descovy).

Truvada is the brand name of a pill containing two drugs: emtricitabine (FTC) and tenofovir disoproxil fumarate (TDF). Those two drugs (sometimes called “FTC/TDF” or “F/TDF”) are also available in generic form under the names Tenvir-EM, Tavir-EM or Ricovir-EM. This combination is approved for both treatment and prevention.

Descovy is the brand name of a pill containing two drugs: emtricitabine (FTC) and tenofovir alafenamide (TAF). Sometimes the term “F/TAF” is used instead of Descovy. This combination is approved for treatment only.

Important Points About the DISCOVER Trial:

  • F/TDF as PrEP is currently the only combination drug product proven to reduce a person’s risk of HIV.
  • While F/TAF has been approved for treatment for HIV, it has not been proven to be effective in keeping an HIV-negative person from becoming infected. Gilead is conducting the DISCOVER trial to determine if Descovy can reduce the risk of acquiring HIV.
  • Descovy has not been proven to be a better, safer, more effective kind of PrEP. The trial is being conducted to determine the safety and efficacy of Descovy as PrEP. It is critical that any communication about this trial and Descovy as PrEP clearly conveys this fact and does not give the false impression that this product is safer, more tolerable or more effective than F/TDF for PrEP.
  • The DISCOVER trial is not a PrEP access trial. Individuals who are at increased risk of HIV acquisition and who are interested in F/TDF as PrEP should be connected to services to discuss risk, important information about PrEP and what is best for them. It is not good practice to enroll participants into any randomized prevention trial who are under the false impression that by enrolling, they will automatically gain access to a method proven to reduce their HIV risk.
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This factsheet was developed by AIDES, AIDS Foundation of Chicago, AIDS Project of the East Bay, AVAC, CARE Center, European AIDS Treatment Group, Howard Brown Health, NMAC,, Project Inform, REZO, San Francisco AIDS Foundation and individual community advocates. Email [email protected] to learn more.