FDA Approves Hibsago, a New Hepatitis B Treatment: Who Qualifies and What Are the Side Effects?

The US Food and Drug Administration (FDA) has approved Hibsago (bepirovirsen), a new treatment for certain adults living with chronic hepatitis B. Approved on October 20, 2026, the medication offers a new approach to controlling the virus and may allow some eligible patients to stop taking their existing hepatitis B medicines under medical supervision.

Developed by GSK, Hibsago is the first FDA-approved antisense oligonucleotide treatment for chronic hepatitis B. It is designed to target the genetic instructions the virus uses to produce viral components, helping reduce the amount of virus and hepatitis B surface antigen in the body.

Chronic hepatitis B is a long-term viral infection that can cause serious liver complications, including cirrhosis and liver cancer. Many patients need antiviral medication for years to keep the infection under control.

Who Is Eligible for Hibsago?

Hibsago is approved for specific adults with chronic hepatitis B who meet the following criteria:

• They do not have cirrhosis, or advanced scarring of the liver.

A liver specialist must assess whether a patient meets these requirements before treatment begins.

How Does Hibsago Work?

Hibsago works by targeting the genetic material involved in hepatitis B virus activity. This helps reduce the production of viral components, including the surface antigen associated with the infection.

The medication is administered as an injection under the skin for up to 24 weeks. Patients continue taking their existing hepatitis B antiviral medication during this period and for at least 24 weeks after their final Hibsago injection.

Some patients may then be able to stop their existing medication if they meet specific medical and laboratory criteria. Treatment must be supervised by a healthcare professional.

Can Hibsago Cure Hepatitis B?

Hibsago offers some patients the possibility of achieving a functional cure. This means that hepatitis B surface antigen becomes undetectable and the virus remains controlled for a sustained period after treatment ends. It does not necessarily mean that every trace of the virus has been eliminated from the body.

In clinical trials, 24% of patients who received Hibsago met the criteria to stop their existing hepatitis B medication, compared with none in the placebo group.

Twenty-four weeks after stopping all hepatitis B treatment, 19% of patients who received Hibsago maintained viral control with undetectable hepatitis B surface antigen.

Although these results are encouraging, not every patient will achieve a functional cure, and continued monitoring remains essential.

What Are the Possible Side Effects?

Hibsago has important safety warnings that patients should understand before starting treatment.

Common side effects include:

• Injection-site reactions, such as redness or discomfort

Serious risks include:

• Severe liver reactions

The medication carries a boxed warning for serious liver reactions and low platelet counts. Doctors may recommend regular blood tests to monitor liver function, platelet levels and other safety indicators throughout treatment.

Patients should promptly report unusual bleeding, significant changes in their health or symptoms that concern them to their healthcare provider.

What Should Patients Know Before Starting Treatment?

Hibsago is not suitable for everyone with hepatitis B. Patients with cirrhosis or those who do not meet the approved laboratory criteria may not qualify for this treatment.

Patients should not stop their current antiviral medication or switch treatments on their own. A specialist must determine whether Hibsago is appropriate and whether stopping existing medication is safe.

The FDA approval applies in the United States. Availability and regulatory approval may differ in other countries, including India.

Conclusion

The FDA approval of Hibsago represents an important development in chronic hepatitis B treatment. By targeting the virus in a different way, the medication may help some eligible adults maintain viral control after stopping all hepatitis B treatment.

However, its benefits must be weighed against potential side effects, and treatment requires careful medical supervision. Patients should consult a qualified liver specialist to understand their eligibility and available treatment options.