One study will be in previously untreated (naive) patients and the other in patients who failed prior treatment (relapsers and nonresponders), an area of great unmet medical need. The two randomized, double-blind, placebo-controlled studies will evaluate the efficacy of boceprevir in combination with Pegintron (peginterferon alfa-2b) and Rebetol (ribavirin, USP) compared to standard of care with Pegintron and Rebetol alone. The company said the two pivotal studies will run concurrently and are projected to enroll a total of more than 1,400 patients at US and international sites.
The primary objective of pivotal study in untreated (naive) patients, known as HCV Sprint-2, is to evaluate the efficacy of 28- and 48-week regimens of boceprevir (800mg TID) in combination with Pegintron (1.5mcg/kg/week) and Rebetol (600-1400mg/day) compared to a control of Pegintron and Rebetol alone for 48 weeks in previously untreated (naive) adult patients with chronic HCV genotype 1. The study is projected to enroll a total of more than 1,000 patients, including a minimum of 150 African-American or black patients.
The primary objective of pivotal study in patients, who failed prior treatment, known as HCV Respond-2 is to evaluate the efficacy of 36- and 48-week regimens of boceprevir (800mg TID) in combination with Pegintron (1.5mcg/kg/week) and Rebetol (600-1400mg/day) compared to a control of Pegintron and Rebetol alone for 48 weeks in adult patients with chronic HCV genotype 1 who failed prior treatment with peginterferon and ribavirin combination therapy. The study is projected to enroll a total of 375 patients.
In both Phase III clinical studies, patients will receive four weeks of treatment with Pegintron and Rebetol prior to the addition of boceprevir. The rationale for this novel treatment paradigm is based on the fact that both Pegintron and Rebetol reach steady-state concentrations by week four, so patients have the protease inhibitor added at a time when the backbone drug levels have been optimized. In addition, the patient’s immune system will have been activated and primed by Pegintron at the time that boceprevir is added to the regimen.