Vir Biotechnology may be pushing ahead with its combination therapy in hepatitis D, but it's pausing further development in hepatitis B while it seeks a suitable partner.
Back in November, Vir arrived at a liver disease conference with phase 2 data showing that two combination regimens utilizing its drugs tobevibart and elebsiran were able to reduce hepatitis B surface antigens. With the news, the company planned to continue the trial to the 24-week stage in order to evaluate whether its cocktail therapy could act as a functional cure for chronic hepatitis B (CHB).
According to the biotech’s fourth-quarter earnings release, Vir still expects this data in the second quarter of the year. But what happens next is up in the air.
The “future advancement” in CHB “will be contingent on securing a worldwide development and commercialization partner” outside of Greater China, Vir said in the release. This is needed to “best enable further development in this area of high unmet need," the company explained.
Earlier this month, GSK made a similar move, ending work on one potential functional cure for hepatitis B as it prioritized another in the form of bepirovirsen.
With future hepatitis B development sidelined for now, Vir will be steaming ahead with plans to launch a phase 3 trial of the tobevibart-elebsiran combo in hepatitis D in the first half of this year. Early efficacy results from a phase 2 trial last summer suggested the treatment may pose a threat to Gilead Sciences' stuttering attempt to capture the hepatitis D market.
Hepatitis D can only infect people if the hepatitis B virus is present. Compared to people with hepatitis B alone, people living with both viruses have a higher risk of irreversible liver damage and life-threatening complications.
No hepatitis D treatments are yet approved in the U.S., where Gilead’s bulevirtide was swatted away by the FDA in 2022. Gilead has since submitted a filing intended to fix the manufacturing and delivery concerns raised in the agency’s complete response letter, and bulevirtide is already available in Europe.
Vir also has two solid tumor-focused dual-masked T-cell engager programs in phase 1 trials, with a third due to enter the clinic in the first half of the year.
“2024 was a year of transformation for Vir Biotechnology as we successfully defined and executed on our renewed strategic direction, focusing our resources on our most promising programs in infectious diseases and oncology,” CEO Marianne De Backer, Ph.D., said in the Feb. 26 release.
“As we enter 2025, we are poised for significant advancement with the initiation of our phase 3 registrational program in chronic hepatitis delta and further clinical progression of our dual-masked T-cell engagers in solid tumors,” De Backer added. “Our disciplined capital deployment and strategic approach to partnerships enable us to maximize value creation from our pipeline and deliver transformative therapies to patients.”