Emerging concepts for the treatment of hepatitis delta.

Hepatitis delta virus (HDV) causes the most severe form of human viral hepatitis and is associated with a higher risk of cirrhosis, liver decompensation and liver cancer. Interferon alpha is the only agent that has demonstrated efficacy to date, although response rates are low and it is associated with significant side effects. A better understanding of the relevant molecular virology has resulted in the identification of new candidate targets. Future therapeutic options are rapidly evolving as several new agents have entered clinical development, including the entry inhibitor myrcludex-B, the nucleic acid polymer REP2139-Ca inhibiting HBV surface antigen secretion, the farnesyltransferase inhibitor lonafarnib that targets virus assembly, and a better tolerated interferon-interferon lambda.