ATLANTA — Among a population of patients with hepatitis C that are typically difficult to treat, sofosbuvir with weight-based ribavirin demonstrated high efficacy, according to study results presented here.
“Our study population was predominantly African American, most of the population had the [interleukin]-23 CT/TT genotype with [genotype]-1a infection, and many also had a high viral load, which are factors that are associated with difficulty in achieving sustained virologic response (SVR) with traditional HCV treatment,” Anu Osinusi, MD, of the National Institute of Allergy and Infectious Diseases, said at the 2013 Conference on Retroviruses and Opportunistic Infections.
Osinusi and colleagues evaluated the 60 patients in two parts. In part one, 10 patients with stage 0 to stage 2 liver fibrosis received 400 mg sofosbuvir (Gilead) and weight-based ribavirin. In part two, 50 patients with stage 0 to stage 4 fibrosis were randomly assigned to 400 mg sofosbuvir once daily wither either low-dose ribavirin (600 mg once daily) or weight-based ribavirin. The patients received treatment for 24 weeks.
The median virologic decline was 4.14 log10 IU/mL by day 7. Among the patients who were in part one of the study, the SVR4, SVR12 and SVR24 was 100%. In part two, the end-of-treatment response was 100% among everyone who completed treatment. However, 10 patients on the low-dose ribavirin regimen and seven patients on the weight-based ribavirin regimen relapsed within 12 weeks of completing treatment.
In part two of the study, the median drug efficacy was 99.97% in both relapsers and among patients who reached SVR. The researchers did not identify any associations between ribavirin dosing, HCV genotype-1 subtype, IL-28B genotype, fibrosis stage and viral kinetic parameters. There also were no serious adverse events or discontinuations due to adverse events.
“The focus of our study was to look at factors that were predictive of treatment response,” Osinusi said. “Although it’s clear now that combination direct-acting antiviral regimens are more beneficial than a single direct-acting antiviral regimen, some of the factors we identified in this population of patients will be promising to look at in other populations.”
For more information:
Osinusi A. #157LB. Presented at: 2013 Conference on Retroviruses and Opportunistic Infections; March 3-6, 2013; Atlanta.
Disclosure: Osinusi reports no relevant financial disclosures.