Vertex Hep C Drug Still Leads Schering

But already, boceprevir has no hope of catching up to telaprevir, which posted final cure rates about 10% higher in its two phase II studies. Those data were presented at a U.S. liver disease meeting last November.

Rates of patient discontinuation and relapse were also relatively high in the boceprevir study presented Saturday, which don't appear to give the drug any discernible edge over the Vertex's telaprevir.

This study is ongoing so there is a lot of data not yet presented, including patients dosed with boceprevir for a longer period and a comparator arm of patients not given boceprevir.

Schering-Plough does plan on moving boceprevir into phase III studies, but with the phase II study still not completed, the company is at least one year behind Vertex, which has already begun its phase III telaprevir studies.

Hepatitis C drug development seems to take twists and turns on a weekly basis, so it's never safe to count any drug in or out. And boceprevir isn't the only competition facing telaprevir. There are promising drugs -- albeit in much earlier stages of development -- from IntermuneITMN, Johnson and JohnsonJNJ, MerckMRK and Boehringer Ingelheim, among others.

With that said, Vertex and its shareholders have to feel good about telaprevir right now.

Bernstein's Porges, by the way, has an outperform rating and a $45 price target on Vertex.