InterMune Up Despite So-So Hep C Data

Updated from 10:39 a.m. EST

SAN FRANCISCO -- InterMune(ITMN Quote) has moved forward with development of a new hepatitis C drug, dubbed ITMN-191, on the premise that it will be more potent and more convenient to administer than a similar drug from Vertex Pharmaceuticals(VRTX Quote).

But new data released Monday morning on ITMN-191 doesn't completely live up to that billing.

A 600 mg dose of ITMN-191 given twice daily and combined with the current standard of care therapy for hepatitis C reduced the amount of virus below detectable levels in 13% of patients treated for 14 days.

Using a less stringent measure of efficacy, 75% of these patients had no detectable virus in their system. InterMune reported the new data on ITMN-191 ahead of the start Monday of the J.P. Morgan Healthcare Conference.

InterMune said it was pleased with the data and that the company and partner Roche plan to move ahead with new ITMN-191 studies in the second quarter. However, Wall Street's biotech investors never evaluate hepatitis C drugs in a vacuum, and in this case, Monday's ITMN-191 data doesn't stack up very well against Vertex's telaprevir.

In a similar 14-day "triple combination" study done in 2006 by Vertex, 25% of telaprevir patients had undetectable levels of virus in their system. That number jumped to 92% when using a less stringent measure of efficacy.

Now, patients in the Vertex study had to take telaprevir every 8 hours, or three times a day, which is less convenient than the twice-daily dosing for InterMune's ITMN-191. If InterMune wins on convenience, Vertex still appears ahead on potency.