-- Continued Treatment with Bulevirtide Shows Clinical Benefit and Sustained Viral Decline with Prolonged Treatment in Patients Originally Considered Partial- or Non-Responders --

FOSTER CITY, Calif.--(BUSINESS WIRE)-- Gilead Sciences, Inc. (Nasdaq: GILD) today announced Week 96 results from the pivotal MYR301 Phase 3 clinical trial evaluating the first-in-class entry inhibitor Hepcludex® (bulevirtide) for the treatment of adults with chronic hepatitis delta (HDV) infection. These new data presented at the European Association for the Study of the Liver (EASL) Congress 2023 reinforce the role of bulevirtide as an efficacious and well-tolerated treatment for the management of chronic HDV. Bulevirtide remains the only approved treatment for HDV in the EU and is not approved in the U.S.

The new findings (OS-068) presented today reinforce the efficacy and safety of bulevirtide and demonstrate that additional improvements in combined response are observed at Week 96 compared with Week 48, with no signs of treatment resistance. An additional analysis from the MYR301 Phase 3 trial presented in a late-breaker (LBP-20) showed that study participants who appeared to not respond or only partially respond to bulevirtide treatment at Week 24, went on to achieve a virologic response at 96 Weeks with continued bulevirtide monotherapy.

“This latest data adds to the growing body of evidence establishing bulevirtide as an effective and well tolerated treatment for HDV when used for a longer duration. Importantly, we saw a response at 96 weeks even in people who initially showed only a partial decline in HDV viral load,” said Heiner Wedemeyer, MD, Director, Department of Gastroenterology, Hepatology, Infectious Diseases and Endocrinology at Hannover Medical School. “These findings demonstrate to clinicians and patients that with prolonged bulevirtide treatment, clinical benefit may be possible.”

The MYR301 Phase 3 data assessing the efficacy and safety of bulevirtide at 96 weeks (OS-068), builds on the Week 48 data shared at EASL’s ILC 2022 and was published yesterday in the New England Journal of Medicine. Study participants receiving either 2 mg or 10 mg bulevirtide achieved similar combined responses (ALT normalization and virological response) at Week 96. The combined virological and biochemical response rates continued to increase through Week 96 compared to Week 48, with response rates of 55% and 56% with 2 mg and 10 mg bulevirtide respectively. The safety profile at Week 96 is consistent with what was observed at Week 48, with no resistance observed and no serious adverse events attributed to bulevirtide treatment. Increases in bile acids without a correlation to pruritus or other symptoms were noted with bulevirtide treatment. Injection site reactions occurred in a higher proportion of study participants receiving 10 mg of bulevirtide.

In a new analysis (LBP-20), study participants treated with bulevirtide monotherapy who experienced suboptimal virological response (non-response or partial-response) at Week 24 were continued on treatment through Week 96. Among study participants who had no response or a partial-response at Week 24, 43% and 82% respectively achieved virological response by Week 96. Virologic response was defined as undetectable HDV RNA or a decrease by ≥ 2 log10 IU/mL from baseline; non-response and partial virologic response was defined as HDV RNA decline of