Hepatitis D can be treated with pegylated interferon, which is also active against hepatitis B. The addition of hepatitis D can make chronic hepatitis B significantly worse and increases the risk of cirrhosis and liver cancer.

Treatment with pegylated interferon does not usually lead to a cure, but can reduce how much both viruses are replicating. Unfortunately, once treatment stops, the hepatitis D viral load often rises again. Nucleoside and nucleotide analogues (lamivudine, adefovir, entecavir, telbivudine, tenofovir) work against hepatitis B, but don’t appear to be effective against hepatitis D.

Combination therapies appear to be promising. In a study published in 2011, a quarter of participants with hepatitis D were cured when they took a combination of peginterferon alfa and adefovir.