FDA approves first-of-its-kind hepatitis B treatment: How Hibsago works, who qualifies and side effects

The US Food and Drug Administration (FDA) has approved a novel treatment for chronic hepatitis B, called Hibsago (bepirovirsen). This injection is given alongside current antiviral medications and is intended for eligible adults without cirrhosis or advanced liver scarring. Chronic hepatitis B is a long-term liver infection that can lead to severe liver disease and increase the risk of liver cancer.

It often requires lifelong treatment with antiviral medicines. Hibsago works by targeting the genetic instructions the virus uses to replicate itself and produce viral proteins, thereby reducing viral levels in the body. Unlike existing treatments, Hibsago may allow some patients to achieve a functional cure, where the virus remains under control without continuous medication.

In clinical trials, 24% of patients who received Hibsago met the criteria to discontinue their regular hepatitis B medicines, compared to none in the placebo group. After 24 weeks of stopping all treatments, 19% of Hibsago recipients maintained control over the virus, with no detectable hepatitis B surface antigen in their blood.

While promising, Hibsago is not a cure, and long-term monitoring is necessary to assess the durability of the response. Common side effects include injection site reactions, fever, fatigue, and headaches, while more serious risks include liver reactions, low platelet counts, kidney function decline, and inflammation of blood vessels.

Patients must have specific health and laboratory criteria, including no cirrhosis, six months of antiviral therapy, and low hepatitis B surface antigen levels, to qualify for Hibsago. A thorough assessment by a liver specialist is required before starting treatment, and regular monitoring is essential to ensure patient safety.