Statement on DISCOVER Study of F/TAF for PrEP

Foster City, Calif. - November 11, 2016 - Gilead Sciences is sponsoring a clinical trial, known as the DISCOVER study, to test whether a combination of emtricitabine and tenofovir alafenamide (F/TAF) is as safe and effective as Truvada® (emtricitabine and tenofovir disoproxil fumarate, F/TDF) at reducing the risk of HIV infection when used as pre-exposure prophylaxis (PrEP). F/TAF was recently approved for HIV treatment, but it is not yet known whether it is effective as PrEP.

Enrollment in the DISCOVER study is ongoing. If proven safe and effective for HIV prevention, F/TAF could be an important new PrEP option. TAF has demonstrated improvement in markers of renal and bone safety compared to TDF, and its lower dose could reduce generic manufacturing costs, leading to lower prices in developing countries.

As always, the health and safety of trial participants is Gilead’s top priority. It is important for anyone considering the DISCOVER study to understand that we do not yet know if F/TAF is effective for PrEP. As with any study Gilead conducts, all potential participants are carefully informed, in their preferred language, of the potential risks and benefits of participation in the study. Trial documents that explain the background and rationale for conducting this study have been carefully written by scientific experts at Gilead, in consultation with external academic experts. Importantly, local and centralized ethics review boards, all investigators and their institutions, health and regulatory authorities in multiple countries, and Gilead legal, regulatory compliance, and business conduct specialists have reviewed and approved these documents prior to implementation at any DISCOVER study site. Because the DISCOVER trial is conducted in a double-blind fashion, participants will not know whether they are receiving Truvada or F/TAF. Participants will receive regular medical check-ups, including testing for HIV and other sexually transmitted infections, as well as HIV counseling and access to condoms.

With helpful feedback from both clinical investigators and community advocates, Gilead has made changes to the trial protocol. These changes include elimination of a 30-day “washout” period in which potential participants were to stop using Truvada for PrEP before entering the trial. In addition, the study language has been made simpler and more patient friendly to reduce any chance for confusion or misinformation.

Input from community advocates also led Gilead to strengthen its guidance to trial sites to ensure that all recruitment materials accurately convey the investigational nature of F/TAF for PrEP. All locally produced materials are reviewed by Gilead for accuracy and completeness, and are also reviewed by local or central ethics boards at academic institutions. In the small number of cases in which trial sites used materials that did not meet these standards, Gilead has worked with investigators to ensure that all potential education and recruitment materials are scientifically accurate and meet strict standards of quality and appropriateness.

Additional community feedback addressed the discussion of risk in consent materials for the DISCOVER trial. Following this feedback, Gilead initiated a review of all consent materials with the study Institutional Review Boards. The review concluded that the current trial consent materials convey risk sufficiently and appropriately.

Consistent with all HIV studies conducted by Gilead, an Independent Data Monitoring Committee (IDMC) has been formed which will review unblinded data from the study to ensure the safety of all participants; for the DISCOVER study this panel includes a community representative.

To strengthen HIV community engagement in the DISCOVER trial, Gilead is establishing community advisory groups in North America and Europe for the study. We are using a community-provided document to help draft terms of reference and membership eligibility, aligned with good participatory practices. Gilead is also forming a permanent, ongoing Community Advisory Council to provide input on many areas of our work, including the design and conduct of HIV prevention, treatment and cure research.

We welcome additional feedback on Gilead’s work in HIV prevention and treatment, and we are committed to ongoing dialogue with community advocates. Anyone with questions or recommendations about the DISCOVER trial can contact

About Gilead Sciences

Gilead Sciences is a biopharmaceutical company that discovers, develops and commercializes innovative therapeutics in areas of unmet medical need.  We strive to transform and simplify care for people with life-threatening illnesses around the world, always keeping the patients and the communities we serve at the forefront.