Chronic hepatitis C, which can lead to cirrhosis, liver failure and liver cancer, continues to be a serious health threat for the African-American population. Not only do black Americans have a disproportionately high incidence of hepatitis C compared to the overall population, they also tend to respond less well to treatments for the disease. So does this mean that developing completely new and different types of hepatitis C drugs is the answer? Not necessarily, according to the surprising results of a recent study led by researchers at Weill Cornell Medical College in New York.
The WIN-R study (Weight-Based Dosing of PEG-INTRON and REBETOL) found that African Americans infected with the most difficult-to-treat form of chronic hepatitis C had significantly higher response rates to the popular combination therapy of REBETOL® (ribavirin, USP) plus PEG-INTRON® (peginterferon alfa-2b) when the REBETOL was given in a dose individualized to the patients’ body weight, rather than a standardized flat dose. In fact, twice as many African-American patients successfully cleared the virus when they were given the weight-based dose of ribavirin, according to data presented last November at the 55th Annual Meeting of the American Association for the Study of Liver Diseases.
The WIN-R study, which involved approximately 4,900 patients nationwide, is the largest prospective hepatitis C clinical study undertaken to date, and it also included the largest number of African-American participants in any study to date. The recommended dose in the U.S. for REBETOL/PEG-INTRON combination therapy is PEG-INTRON 1.5 mcg/kg/week and REBETOL 800/mg/day for 48 weeks. The WIN-R patients were randomized to receive the REBETOL as either a flat dose (800 mg) or a weight-based dose of 800 mg, 1,000 mg, 1,200 mg or 1,400 mg for body weights of less than 65 kg, 65 to 85 kg, 86 to 105 kg and 106 to 125 kg, respectively. (A kilogram equals approximately 2.2 pounds.)
“It’s important to note that in this study the overall safety of weight-based ribavirin dosing was similar to that of the flat 800 mg dose,” says the study’s principal investigator, Ira M. Jacobson, MD, a professor of clinical medicine at Weill Cornell Medical College. He adds, “The large amount of data in African-American patients generated by the WIN-R study add to our body of knowledge about how to best treat the disease, but it’s important to do additional research to improve outcomes for these patients.”