Interferon Alone Effective for Hepatitis B
Some Patients May Do as Well With Single Drug Rather Than Combination
Jan. 6, 2004 - Treating chronic hepatitis B remains a challenge, but new research shows that a long-acting version of an old hepatitis drug works just as well as a combination approach.
A year of treatment with a long-acting interferon called Peg-Intron led to a sustained response in just over a third of patients. The response rate was higher than is typically reported with other treatments and was as effective as the combination of Peg-Intron and another hepatitis B drug, Epivir.
The findings are published in the Jan. 8 issue of the journal The Lancet.
"Patients on the combined therapy had a higher initial response rate, but the sustained responses were the same at (six months) follow-up," lead researcher Harry Janssen, MD, tells WebMD.
Worldwide, more than 350 million people, including 1.25 million Americans, are chronically infected with hepatitis B. The virus is transmitted through body fluids and is 100 times more contagious than HIV. About 40% of chronically infected people who do not respond to treatment eventually develop potentially life-threatening liver disease. Symptoms typically do not occur until several decades after infection.
Recent research suggests that interferon in its longer-acting pegylated form is a more effective treatment for hepatitis B than the older, standard version of the drug. Two pegylated interferons are available, Pegasys and Peg-Intron. Peg-Intron's manufacturer, Schering-Plough, partially funded the current study.
In this study, which included patients from 15 countries in Europe, East Asia, and North America, Janssen and colleagues treated 307 patients with Peg-Intron for one year. Some patients also received Epivir.
Patients in both treatment groups received 100 micrograms per week of Peg-Intron for eight months, followed by 50 micrograms per week for the remaining four months of treatment.
At the end of treatment 44% of the patients in the combination group had cleared the virus, compared with 29% treated with the interferon alone. Roughly six months later, however, sustained viral clearance was almost identical among the two groups -- 36% for those treated with interferon alone and 35% for those who received the combination treatment.
Virus Type Matters
The study by Janssen and colleagues is one of the first to suggest that the genetic makeup (genotype) of the virus helps predict treatment outcome. It's well known that genotype affects hepatitis C treatment, but that has not been thought to be important in hepatitis B.
Response rates among patients with genotypes A and B averaged 45%, compared with about 27% among patients with genotypes C and D. The A and B genotypes are more common among whites, while C and D genotypes are more commonly seen in Asian populations.
"This is the first prospective evidence indicating that genotype is an important predictor of treatment response for hepatitis B in the same way that it is for hepatitis C," Janssen says.