Interferon alfa, a human protein produced in large quantities through genetic engineering techniques, may have a role in treating some patients with chronic hepatitis, according to two reports in today’s New England Journal of Medicine.
Researchers from the National Institutes of Health and a consortium of medical centers headed by the University of Florida said in separate studies that about half the patients with chronic hepatitis C, a viral infection of the liver, improved following 24 weeks of interferon treatment.
But the NIH researchers acknowledged that “the beneficial responses are often transient” and the other research team said that “relapse after the cessation of treatment is common.”
The studies involved a total of 207 patients. About two-thirds of the patients were treated with three-times-a-week injections of interferon. The others received placebo injections.
Response to the treatment was measured through blood tests of liver function and examination of liver tissue under the microscope before and after therapy.
An editorial which was also published in the medical journal cautioned that the impact of interferon alfa treatment “on the long-term course of the disease was unclear.”
“Making therapy with interferon routine will require better definition of eligible patients and the development of more effective treatment regimens,” the editorial stated. It was written by Miriam J. Alter of the U.S. Centers for Disease Control in Atlanta and Dr. Richard E. Sampliner of the University of Arizona Health Sciences Center in Tucson.
Hepatitis C, not the AIDS virus, is the most common serious infection that can be transmitted through blood transfusions. A screening test for the virus, which was previously known as non-A, non-B hepatitis, has only recently been developed. Widespread use of that test to screen blood is expected to begin in the near future.
Hepatitis C infection often causes no symptoms, but some infected individuals may develop life-threatening chronic liver disease, such as cirrhosis.
Approximately 150,000 non-A, non-B hepatitis infections occur in the United States annually, according to a Centers for Disease Control estimate. Between 7,500 to 15,000 infections are thought to result from blood transfusions. Many of the other infections are thought to be related to intravenous drug use or sexual exposures.