GSK scores regulatory wins for chronic hepatitis B drug, cancer therapy

Aug 24 (Reuters) – GSK said on Monday its experimental chronic hepatitis B drug received its first global approval in Japan, and a key cancer therapy was granted a priority U.S. regulatory review as a possible rectal cancer treatment.

Here are some details:

• The British drugmaker said bepirovirsen, to be branded as Hibsago, has been approved in Japan as the first and only functional cure for chronic hepatitis B in the country.

• GSK said the approval was based on late-stage studies, which showed that the drug helped nearly one-in-five patients achieve a functional cure and raised hopes for a finite treatment course as an alternative to lifelong antiviral ​pills.

• Bepirovirsen is designed to tackle hepatitis B in three ways: by blocking viral DNA replication, lowering hepatitis B surface antigen levels in the blood, and boosting immune response for longer-lasting control of the disease.

• GSK has predicted bepirovirsen could bring in over £2 billion ($2.73 billion) in peak annual sales, taking it closer to its annual revenue target of more than £40 billion by 2031 as its pipeline development comes into focus.

• Separately, GSK said the U.S. FDA will conduct a priority review of dostarlimab, marketed as Jemperli, as a potential treatment for a type of rectal cancer alongside existing approvals of specific endometrial ​cancer subtypes.

• The FDA has assigned a February 2027 action date for the rectal cancer review, with the program structure possibly yielding a decision earlier as well.

• Jemperli, which had also received both Breakthrough Therapy and Fast Track designations by the FDA, is not currently approved anywhere in the world for locally advanced rectal cancer.

($1 = 0.7332 pounds)

(Reporting by Ankita Bora in Bengaluru; Editing by Mrigank Dhaniwala)