Dive Brief:

• GSK and Ionis Pharmaceuticals said their experimental hepatitis B medicine succeeded in two Phase 3 trials, offering patients what might be a “functional cure” for the disease.
• In releases issued Wednesday, the companies didn’t provide details on the effects seen in the B-Well 1 and B-Well 2 studies. The drug, bepirovirsen, met the primary endpoint in both trials and “demonstrated a statistically significant and clinically meaningful functional cure rate,” the companies said.
• Global regulatory filings are planned for the first quarter of this year based on the data, the companies said. Researchers plan to release the full results at a future medical meeting and in a peer-reviewed journal.

Dive Insight:

Health officials estimate that more than 2 billion people around the world have been infected with the hepatitis B virus and almost 300 million of those patients have developed chronic infections that can lead to cirrhosis and liver cancer. Infants exposed to the virus are especially at risk, with as many as 90% of those unvaccinated against it developing a chronic infection.

Many patients with chronic hepatitis B end up taking antiviral drugs for life. With bepirovirsen, GSK and Ionis believe they can offer patients a six-month course of treatment that pushes the hepatitis B to undetectable levels. That functional cure might allow patients to stay off medicine and still avoid the harmful effects of the virus.

Analysts say they see a clear market demand for effective hepatitis B therapies; Gilead’s Vemlidy was on track to top $1 billion in sales last year, based on third-quarter data. A little less than half of the drug’s revenue has come from the U.S., the world’s biggest pharmaceutical market.

In the U.S., infections in infants, children and young people dropped 99% after government health officials in 1991 began recommending universal vaccination for infants. But the Trump administration is now trying to dismantle that process. U.S. health officials this week reduced the number of universally recommended inoculations for children, axing hepatitis B shots from the list following the advice of a committee overhauled by Health and Human Services Secretary Robert F. Kennedy Jr., a vaccine skeptic.

Ionis developed bepirovirsen and licensed it to GSK in 2019. The company is eligible to receive as much as $150 million more in payments for reaching certain regulatory and sales milestones as well as royalties of 10% to 12% on net sales if the drug reaches the market. For GSK, the successful study offers the possibility of another win for its pipeline after approval of a key asthma drug last month.