- GSK said Wednesday it has begun two Phase 3 trials of bepirovirsen, an experimental medicine the British drugmaker hopes may offer a functional cure for hepatitis B.
- The company highlighted the drug on its fourth quarter earnings call as one of several priority treatments it now has in testing. “Our aim is for bepirovirsen to become a backbone of future therapy,” said Chief Scientific Officer Tony Wood on the call.
- The two Phase 3 trials, dubbed B-Well 1 and B-Well 2, are designed to test bepirovirsen against a placebo in patients who will also be treated with available therapies called nucleoside or nucleotide analogues. Both studies should produce results on their main goal in October 2025, according to a federal clinical trials database.
Chronic hepatitis B affects more than 300 million people, or about 4% of the world’s population, and leads to the death of hundreds of thousands of people each year.
Currently, patients can keep their infection under control with nucleoside or nucleotide treatments such as Bristol Myers Squibb’s Baraclude and Gilead’s Viread. But there’s a need for a drug that can clear hepatitis B from the body and allow patients to stop therapy altogether. That’s where GSK’s bepirovirsen comes in.
The drug is an oligonucleotide and targets RNA to weaken the hepatitis B virus’ hold on the body. (In addition to bepirovirsen, GSK has another oligonucleotide therapy in Phase 2 to treat non alcoholic steatohepatitis, or NASH, and recently signed a four-year deal to develop more medicines of this type with Wave Life Sciences.)
A Phase 2 trial published in The New England Journal of Medicine in November suggested bepirovirsen could clear hepatitis B from the body in some patients. GSK also has more Phase 2 trials underway looking at bepirovirsen in sequential combination with other therapies and results from one of those studies, dubbed B-Together, should be available this year.
GSK’s approach — and those of other companies pursuing RNA therapies — has spurred the interest of researchers in the field, including Jay Hoofnagle, director of the liver disease research branch at the National Institute of Diabetes and Digestive and Kidney Diseases. “A new era in the control of hepatitis B may be at hand,” Hoofnagle wrote in an editorial in the New England Journal of Medicine.
For GSK, bepirovirsen is an important asset in an infectious disease division that looks particularly strong. The company is a major player in vaccines, and sales of its Shingrix shot for shingles jumped 72% last year to almost 3 billion pounds, or about $3.7 billion. It also has an RSV vaccine for older adults under review in the U.S., European Union and Japan and is working on an antibiotic for urinary tract infections.