, a multinational phase 2b open-label study in Europe found.
The combination resulted in higher rates of HDV RNA suppression levels at 24 weeks after end of treatment, especially at a higher, 10-mg dose of bulevirtide, according to researchers led by Tarik Asselah, MD. PhD, a professor of medicine and hepatology at Hôpital Beaujon, APHP, Clichy, France, and the University of Paris.
“This response appeared to be maintained from 24-48 weeks after the end of treatment — a finding that supports the concept that sustained undetectable HDV RNA for at least 1 year after treatment is possible in patients with chronic hepatitis D who have been treated with a finite duration of therapy of at least 96 weeks, including 48 weeks of peginterferon alfa-2a therapy,” the investigators wrote in The New England Journal of Medicine.
“As of today, there is no approved treatment for chronic HDV infection in the United States. Pegylated interferon alfa-2a, which is not approved for treatment of HDV, is the only option recommended by US treatment guidelines,” said study corresponding author Fabien Zoulim, MD, PhD, a hepatologist at the Lyon Hepatology Institute and a professor of medicine at the University of Lyon in France, in comments to GI & Hepatology News. “Bulevirtide 2 mg is approved for treating chronic HDV and compensated liver disease, and both bulevirtide and peginterferon are recommended options by the European treatment guidelines.”
The study found that most patients with undetectable HDV RNA levels during treatment-free follow-up showed no reduction in HepB surface antigen (HBsAg), suggesting an undetectable HDV RNA level can be achieved and sustained without HBsAg loss, the authors wrote.
While very small numbers in the combo groups and the higher-dose bulevirtide arm cleared HBsAg, “the study was not powered to evaluate the HBsAg response,” Dr. Zoulim said.
HDV is a defective virus that requires HBsAg for assembly and propagation, the authors noted. It affects as many as 20 million persons worldwide, and as the most severe form of chronic viral hepatitis, is associated with 2-6 times the risk of hepatocellular carcinoma and 2-3 times the risk of death associated with HBV monoinfection.
Though not common in the United States, it affects an estimated 10 to 20 million people worldwide (J Hepatol. 2020 Apr. doi: 10.1016/j.jhep.2020.04.008). One US database study found HepD in 4.6% of patients with HepB infection.
Commenting on the study but not a participant in it, Ahmet O. Gurakar, MD, AGAF, a professor of medicine in the sections of gastroenterology and hepatology at Johns Hopkins School of Medicine in Baltimore, Maryland, said the study findings look promising for the future treatment of HepD, but cautioned that it will be “a slow process to get approval for combination therapy with bulevirtide since the FDA has previously said it needs to see more studies. The findings need to be confirmed in larger groups, but it’s difficult to recruit enough patients in the United States for a trial since hepatitis D is not common in this country — it’s more common in the Mediterranean basin Eastern European populations.”
Dr. Ahmet O. Gurakar
