First Hepatitis D Drug: Should People With Hepatitis B Ask About Testing?

If you know you have hepatitis B, this is a reasonable time to ask whether you have ever been tested for hepatitis D. That question became more timely on May 22, 2026, when the FDA approved Hepcludex, the first FDA-approved treatment in the United States for chronic hepatitis D.

The approval does not mean everyone with hepatitis B has hepatitis D, and it does not yet prove the new drug prevents liver failure, liver cancer, transplant, or death. But CDC says people diagnosed with hepatitis B should consider hepatitis D testing, so this approval is a practical prompt to check whether that step was ever taken.

Why this matters now

Hepatitis D is a liver infection caused by the hepatitis D virus, or HDV. CDC says only people with hepatitis B can get it. It is considered uncommon in the United States, but CDC also notes that hepatitis D is not a nationally notifiable condition, so the true U.S. count is uncertain.

It can also be serious. CDC says hepatitis D can cause more severe disease than hepatitis B alone, especially when someone with chronic hepatitis B later gets hepatitis D. Symptoms can include dark urine or clay-colored stools, tiredness, fever, joint pain, loss of appetite, nausea, stomach pain, vomiting, and jaundice.

Who should ask more urgently about testing

If you have hepatitis B, the simplest next step is to ask whether you have ever had hepatitis D testing and what the result showed. CDC specifically says people diagnosed with hepatitis B should consider testing for hepatitis D.

An American Association for the Study of Liver Diseases explainer on U.S. screening practice says testing is often missed. It highlights several situations that deserve closer attention: a new hepatitis B diagnosis, hepatitis B with elevated ALT despite relatively low HBV DNA, coinfection with HIV or hepatitis C, injection-drug use, men who have sex with men, multiple sexual partners or a history of sexually transmitted infections, and immigration from regions where hepatitis D is more common.

If an antibody test suggests hepatitis D, the same AASLD summary says an HDV RNA test is used to confirm ongoing infection.

What the new drug is

According to the FDA prescribing information, Hepcludex, also called bulevirtide-gmod, is approved for adults with chronic hepatitis D who do not have cirrhosis or who have compensated cirrhosis. It is given once daily as a subcutaneous injection. The label also says the underlying hepatitis B infection should be managed as clinically appropriate.

What the trial showed

The main FDA evidence came from MYR301, a phase 3 randomized, open-label trial in 101 adults. For the first 48 weeks, one group received daily Hepcludex and the delayed-treatment group did not receive hepatitis D treatment.

At week 48, the FDA materials say 48% of people in the immediate-treatment group met the trial’s combined response measure, compared with 2% in the delayed-treatment group. That combined response was based on lab markers: a drop or disappearance of HDV RNA plus normalization of ALT, a liver enzyme. The FDA label also reports that 20% of treated participants had undetectable HDV RNA at week 48, rising to 36% at week 96 and 50% at week 144.

What the approval does not yet prove

This was an accelerated approval. The FDA prescribing information says the approval is based on improvements in HDV RNA and ALT, and that improvement in disease-related clinical outcomes has not been established. In plain language, the drug has not yet been shown to reduce long-term outcomes such as liver failure, liver cancer, transplant, or death.

A longer-term peer-reviewed report of MYR301 indexed in PubMed adds another important limitation: response rates fell after treatment stopped. At the end of treatment, combined response rates were in the mid-50% range across study groups, but by 96 weeks of follow-up after discontinuation they had dropped to 24% across groups. That suggests some people may need ongoing therapy, and the best treatment duration is still not fully settled.

Safety questions to know about

The FDA label includes a boxed warning that severe flare-ups can happen after Hepcludex is stopped, including hepatitis worsening and liver decompensation, especially in people with cirrhosis. Common side effects in the trial included injection-site reactions, headache, abdominal pain, fatigue, and itching.

Because this is a newly approved treatment for a rare disease, readers should expect practical access questions to come up. The FDA and CDC materials explain who the drug is for, but they do not resolve plan-by-plan issues such as coverage, out-of-pocket costs, or how quickly people can see a liver specialist.

What readers can do now

If you know you have hepatitis B, ask whether you have ever been tested for hepatitis D and whether follow-up HDV RNA testing is needed.
If you were recently diagnosed with hepatitis B, ask what monitoring and specialist follow-up you need, including whether hepatitis D testing makes sense in your case.
If you are not vaccinated against hepatitis B, ask a clinician or pharmacist about vaccination. CDC says hepatitis B vaccination also protects against hepatitis D.
If you develop symptoms such as jaundice, dark urine, severe fatigue, nausea, vomiting, or stomach pain, seek medical care promptly. CDC says a blood test is needed to confirm hepatitis D.

The bottom line

The first FDA-approved hepatitis D drug is important news. But for many readers, the more immediate question is simpler: if you have hepatitis B, have you ever been checked for hepatitis D? This approval is a good reason to ask.

Sources

Editorial note: Weence articles are researched from cited public-health, medical, regulatory, journal, and reputable news sources and may be drafted with AI assistance. They are checked for source support, clarity, and safety guardrails before publication.

This article is for general informational purposes only and is not medical advice. Research findings can be early or incomplete, and health guidance can change. Always talk with a qualified healthcare professional about personal symptoms, diagnosis, medications, vaccines, screenings, or treatment decisions. If you think you may have a medical emergency, call emergency services right away.