Clinical

Adherence to HCV therapy helps boost response

Last Updated: 2009-01-30 16:47:19 -0400 (Reuters Health)

NEW YORK (Reuters Health) - High adherence to hepatitis C virus (HCV) therapy prompts significantly better response than does suboptimal drug exposure, Philadelphia-based researchers report in the January 15th issue of Clinical Infectious Diseases.

As lead investigator Dr. Vincent Lo Re III told Reuters Health, "we found that adherence of 85% or more to the hepatitis C treatment regimen of PEG-interferon and ribavirin, as measured by pharmacy refill data, was associated with increased hepatitis C viral suppression and early virologic response to treatment."

Dr. Lo Re of University of Pennsylvania School of Medicine in Philadelphia and colleagues studied 188 patients and compared the relationship between drug refills and HCV suppression.

At 12 weeks, patients with 85% or greater adherence showed a mean decrease in HCV load that was 0.66 log IU/mL greater than was the case in those with lower adherence. In those with high adherence, the mean decrease amounted to 1.0 log IU/mL.

Early response was also more common in the higher than the lower adherence group. For pegylated interferon, the proportion was 73% versus 29%. For ribavirin, the corresponding values were 73% and 55%. The researchers note that "adherence level to one medication corresponded in most cases to a similar level of adherence to the other medication."

Dr. Lo Re concluded that "identifying suboptimal...adherence to PEG-interferon and/or ribavirin using pharmacy refill data could allow hepatitis C providers to help patients to improve their adherence during treatment, which could help improve response rates."

Clin Infect Dis 2009;48:186-193.