Chronic hepatitis delta virus (HDV) infection patients are currently bereft of approved treatment options in the U.S., but that could soon change thanks in part to a positive readout from one of Gilead Sciences’ recently acquired liver disease prospects.
Gilead’s potential first-in-class entry inhibitor Hepcludex, also known as bulevirtide, helped patients with chronic HDV chart “significant” viral declines after 48 weeks, new late-stage data from the company’s MYR301 trial show. Meanwhile, the drug also triumphed in “almost all assessed health-related quality-of-life domains” on the Hepatitis Quality of Life questionnaire, which measured patient-reported outcomes (PROs) over the same 48-week stretch.
Gilead figures those efficacy wins, plus the med’s promising safety profile, “reinforce the clinical utility of bulevirtide as a monotherapy for the treatment of chronic HDV.” HDV is the most severe form of viral hepatitis. There are currently no other approved therapies for HDV and people living with the condition typically have a poor prognosis, Gilead noted.
HDV is known as a “satellite virus” because it only infects people who are also infected with hepatitis B, the Centers for Disease Control and Prevention explains.
Conditionally approved in Europe back in 2020, Hepcludex is currently under review in the U.S., where the med boasts breakthrough therapy and orphan drug tags from the FDA, Gilead said in its release. The company submitted its U.S. application for Hepcludex in the fourth quarter of 2021, specifically seeking approval for a 2-mg injection for adults with HDV and compensated liver disease.
Hepcludex was central to Gilead’s €1.15 billion buyout of German biotech MYR back in late 2020. At the time, Gilead suggested its MYR takeover would “accelerate” Hepcludex’s global launch and equip the company with an immediate revenue stream in Europe.
Jefferies analysts last year predicted Hepcludex could reap sales of $238 million in 2023.
Separately, BTIG analysts have said the acquisition is “validating for the HDV space, especially with a company with such material experience in antiviral therapeutics as Gilead.” RBC Capital Markets analysts, for their part, said in 2020 that the deal was unlikely to have a “major” impact for Gilead, but explained that it “makes clear strategic sense."
Taking a closer look at Gilead’s 48-week data, patients treated with either Hepcludex 2mg or 10mg scored “significantly greater combined virological and biochemical response”—45% and 48%, respectively—when compared to study participants who hadn’t been given antiviral treatment at this stage of the study, Gilead said.
The drug also won out in patient-reported outcomes and notably, participants on Hepcludex 2mg reported “significant improvements in performance of daily activities related to hepatitis, emotional impact of hepatitis and improvement in work compared with controls,” the company added.
Safety was on par with prior reports, Gilead said, adding that no study participants had to quit taking the med because of side effects. Further, there were no serious adverse events tied to treatment with Hepcludex, the company said.
“What we now see is that treatment with bulevirtide not only improves clinical measures associated with viral control but can significantly improve, and maintain, a range of quality-of-life markers in people living with HDV, ultimately improving the overall management of the condition,” Anu Osinusi, vice president of clinical research for hepatitis, respiratory and emerging viruses at Gilead, said in a statement.