Mirum's liver infection drug lowers virus levels in late-stage study (updated)

Mirum Pharmaceuticals

28/09/2026 16:23

Adds peak sales estimate in bullet 5, analyst comment in bullet 6
By Sneha S K
Sept 28 (Reuters) - Mirum Pharmaceuticals MIRM.O on Monday said its experimental hepatitis drug reduced levels of the virus in patients, meeting the main goal of a late-stage study.
Here are some key details:
Mirum was testing brelovitug, an experimental monoclonal antibody that binds to the hepatitis B surface antigen, a protein found on the surface of the virus
The company was testing the treatment for chronic hepatitis delta virus, a liver infection that affects people already infected with hepatitis B
The disease, which the company estimates affects about 230,000 people in the US and Europe, can cause severe symptoms that can lead to liver damage and, in some cases, death 
At 24 weeks, 56% of patients given 300 milligrams of brelovitug and 45% of those given 900 milligrams showed reduced hepatitis D virus levels and normal liver enzyme levels, compared with 0% in the delayed-treatment group, the company said
The company expects the drug to generate peak sales of at least $1 billion
The only FDA-approved treatment for the condition is Gilead's GILD.O Hepcludex
"Brelovitug has a better benefit/risk profile," said RBC Capital Markets analyst Lisa Walter, adding that the latest results position it as the best-in-class treatment option
The drug was well tolerated across dose groups, with a safety profile consistent with previously reported data, Mirum said
Full results from the study will be presented at an upcoming medical congress, with the company expecting to submit a marketing application for the drug to the US FDA in the first half of 2027.

 (Reporting by Sneha S K in Bengaluru; Editing by Jonathan Ananda and Diti Pujara)
 ((Sneha.SK@thomsonreuters.com;))