Medgenics Inc. has applied for orphan drug designation with the Food and Drug Administration (FDA) for Infradure, an implantable “biopump” of patients’ own cells that have been altered to produce antiviral proteins, for the treatment of chronic hepatitis D virus (HDV) infection, according to a company statement.

HDV is an incomplete virus that requires the helper function of the hepatitis B virus (HBV) to reproduce in the liver. As such, HDV only occurs among people living with HBV. Infection with both viruses significantly increases the risk of cirrhosis and liver cancer.

HDV is rare in the United States, affecting fewer than 200,000 people. To encourage research and development of drugs helpful to small populations, the FDA can grant orphan drug designation to a potential medicine. This provides access to grant money, tax credits, seven years of market exclusivity and the possibility of an expedited review process. It also allows researchers to perform smaller trials, as the relatively small number of people with conditions like hepatitis D can make it difficult to assemble enough participants for Phase III trials. Medgenics says Infradure qualifies for orphan drug status.

Infradure involves taking a tissue sample from the patient, modifying the cells in the sample to produce anti-HDV proteins such as interferon, and surgically re-implanting the altered cells under the skin where they can deliver the treatment directly into the bloodstream.

“The current treatment for hepatitis D requires years of weekly injections of interferon alpha, which leads to patient discomfort and substantial compliance challenges,” said Bruce Bacon, MD, former president of the American Association for the Study of Liver Disease and a member of Medgenics’ advisory board. “Oral antiviral treatments [for HDV] have proven to be ineffective. Infradure is intended to be implanted infrequently, with a single administration potentially replacing many months of weekly injections.”

Medgenics hopes to receive orphan drug designation for Infradure this summer. The company is also waiting on final regulatory approval to perform clinical trials for a similar treatment, Epodure, designed to help manage the anemia and fatigue associated with the hepatitis C virus (HCV) treatment.