Foster City, Calif., June 10, 2025 – The U.S. Food and Drug Administration has placed a clinical hold on Gilead’s HIV treatment trials of GS-1720 (an investigational integrase strand transfer inhibitor) and/or GS-4182 (an investigational capsid inhibitor). The clinical hold is due to the identification of a safety signal of decreases in CD4+T-cell (CD4) and absolute lymphocyte counts in a subset of participants receiving the combination of GS-1720 and GS-4182.
Clinical trial investigators involved in the trials have been informed of these actions. GS-1720 and GS-4182 are investigational agents and have not been approved anywhere globally. We intend to investigate and pursue the potential of both agents and are committed to working with regulatory authorities to resolve the issues underlying the clinical hold.
Gilead has multiple other long-acting oral and injectable investigational HIV treatment combinations under evaluation in clinical and preclinical studies, including combinations with weekly, monthly, quarterly, and twice-yearly dosing. This hold does not impact these combinations or their respective clinical or pre-clinical development programs.
The safety of individuals taking Gilead medicines is our foremost priority and we remain focused on pursuing advances to improve outcomes and expand options for people living with HIV.
The following studies have been placed on clinical hold:
Three additional Phase 1 trials of either agent and/or their combinations are also on hold.
About Gilead Sciences
Gilead Sciences, Inc. is a biopharmaceutical company that has pursued and achieved breakthroughs in medicine for more than three decades, with the goal of creating a healthier world for all people. The company is committed to advancing innovative medicines to prevent and treat life-threatening diseases, including HIV, viral hepatitis, COVID-19, cancer and inflammation. Gilead operates in more than 35 countries worldwide, with headquarters in Foster City, Calif.