Gilead Receives Complete Response Letter from U.S. FDA for Bulevirtide for the Treatment of Adults with Hepatitis Delta Virus

Foster City, Calif., October 27, 2022 – The U.S. Food and Drug Administration (FDA) has issued a complete response letter (CRL) for the Biologics License Application (BLA) for bulevirtide, an investigational entry-inhibitor for the treatment of adults with hepatitis delta virus (HDV) infection and compensated liver disease. In the CRL, the FDA cited concerns regarding the manufacture and delivery of bulevirtide. No new studies to evaluate the safety and efficacy of bulevirtide have been requested. There are currently no approved products for the treatment of HDV in the U.S.

“While we are disappointed with this outcome, we remain confident in the benefits bulevirtide could potentially bring to people living with HDV in the U.S. Today’s news does not change the safety and efficacy profile observed in clinical trials to date. We look forward to continuing our active discussions with FDA so that we may bring bulevirtide to people living with HDV in the U.S. as soon as possible,” said Merdad Parsey, MD, PhD, Chief Medical Officer, Gilead Sciences.

Since the acquisition of MYR GmbH and bulevirtide in 2021, Gilead has been working to implement process improvements to the manufacturing of bulevirtide. Gilead will continue to discuss manufacturing and product delivery improvements with the FDA.

Chronic HDV infection is the most severe form of viral hepatitis, with a poor prognosis and high rates of mortality. There is a significant unmet need for HDV treatment options in the U.S. Bulevirtide was granted Breakthrough Therapy and Orphan Drug designations by the FDA. Bulevirtide is not approved by the U.S. FDA and is conditionally authorized under the tradename Hepcludex® in the European Economic Area  and the United Kingdom.

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 and cancer. Gilead operates in more than 35 countries worldwide, with headquarters in Foster City, California.

Forward-Looking Statements
This press release includes forward-looking statements within the meaning of the Private Securities Litigation Reform Act of 1995 that are subject to risks, uncertainties, and other factors, including Gilead’s ability to resolve the issues cited by the FDA in the CRL to the satisfaction of the FDA and the risk the FDA may not approve the BLA for bulevirtide for the treatment of adults with HDV infection and compensated liver disease, in timely manner or at all. As a result, bulevirtide may never be successfully commercialized in the United States. These and other risks, uncertainties and factors are described in detail in Gilead’s Quarterly Report on Form 10-Q for the quarter ended June 30, 2022, as filed with the U.S. Securities and Exchange Commission. These risks, uncertainties and other factors could cause actual results to differ materially from those referred to in the forward-looking statements. All statements other than statements of historical fact are statements that could be deemed forward-looking statements. The reader is cautioned that any such forward-looking statements are not guarantees of future performance and involve risks and uncertainties and is cautioned not to place undue reliance on these forward-looking statements. All forward-looking statements are based on information currently available to Gilead, and Gilead assumes no obligation and disclaims any intent to update any such forward-looking statements. 

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