April 26, 2011
A Food and Drug Administration review found Merck & Co.'s new hepatitis C drug cures more patients in less time than current therapies, though some safety questions remain. FDA's analysis was posted Monday ahead of a public meeting Wednesday on whether to approve boceprevir.
And on Thursday, a similar drug made by Vertex Pharmaceuticals Inc. will be considered by FDA's panel. Both medicines are protease inhibitors, blocking an enzyme that allows hepatitis C virus to replicate. The tablets differ from the standard HCV treatments, ribavirin and interferon-alpha, which are designed to boost the immune system.
The two studies submitted by Merck show boceprevir patients had undetectable HCV levels six months post-treatment. Boceprevir plus standard treatment boosted cure rates to 60 percent-65 percent, compared with 40 percent for traditional HCV drugs alone. In addition, the studies indicate that adding boceprevir to standard HCV therapy helped cut treatment time in half, reducing exposure to the older drugs' side effects.
But FDA scientists said some late-responding patients may need to take the boceprevir combination for eight months. In addition, African Americans were among other groups who should receive longer therapy. Blacks, who comprise 20 percent of persons with HCV, had a cure rate 15 percent-25 percent lower than other racial groups. FDA also questioned boceprevir's efficacy in patients who have failed standard treatment.
Boceprevir was associated with an "increased frequency and severity of anemia," FDA said, requiring further review. And though the agency found an increased number of reported symptoms of "suicidal and homicidal ideation" with boceprevir, FDA noted "it is difficult to make any meaningful clinical conclusion from this observation."
FDA is scheduled to make a final decision on boceprevir in May. To access the agency briefing, click here.