Treatment response remains suboptimal for many patients with chronic Hepatitis C, particularly those with genotype 1 and high levels of viremia.
Dr Michael Fried and colleagues from North Carolina, USA compared the efficacy of high-dose regimens of peginterferon alfa-2a and ribavirin with conventional dose regimens in patients with features predicting poor treatment responses.
The research team evaluated eligible treatment-naïve adults with genotype 1 infection, Hepatitis C virus RNA over 800,000 IU/mL, and body weight more than 85 kg.
The patients were randomized to double-blind treatment with peginterferon alfa-2a at 180 or 270 g/week plus ribavirin at 1200 or 1600 mg/day for 48 weeks.
|Higher fixed doses of ribavirin may increase sustained virologic response rates|
The primary endpoint was viral kinetics during the first 24 weeks of therapy.
Among patients receiving peginterferon alfa-2a the magnitude of Hepatitis C RNA reduction was greater than for patients randomized to the conventional dose of peginterferon alfa-2a (180 g/week) for the pairwise comparison for ribavirin at 1600 mg/day.
Patients randomized to the highest doses of peginterferon alfa-2a (270 g/week) and ribavirin (1600 mg/day) experienced the numerically highest rates of sustained virologic response, and the lowest relapse rates.
The team noted that the arm with the higher doses of both drugs was less well-tolerated than the other regimens.
Dr Fried’s team commented, “Higher fixed doses of peginterferon alfa-2a (270 g/week) and ribavirin (1600 mg/day) may increase sustained virologic response rates compared with lower doses of both drugs in patients with a cluster of difficult-to-treat characteristics.”