Tracking Vertex

Yesterday at the Goldman Sachs health care conference, Vertex Pharmaceuticals (Nasdaq: VRTX  ) announced progress for its lead drug candidate, hepatitis C treatment telaprevir, which is partnered with Johnson and Johnson (NYSE: JNJ  ) . Vertex also hinted at what future clinical trial results could look like for the drug.

Two months ago, Vertex released positive interim phase 2 study results for telaprevir in a study dubbed Prove 1. Vertex now plans on releasing more trial results later this year. These results will focus on how patients have fared 12 weeks after the cessation of therapy.

Post-treatment follow-up results like this are so important with hepatitis C patients because those who have undetectable levels of the virus after treatment is completed usually do not experience the virus rebounding in their systems again. Therefore the upcoming Prove 1 12-week post-treatment data will provide a good approximation of telaprevir's efficacy in the long run.  

Vertex also enticed investors by mentioning that another phase 2 study of telaprevir, named Prove 2, had produced "preliminary results (that) are consistent with findings reported for Prove 1." As these results are only preliminary, there's always the chance for a nasty surprise. But with preliminary Prove 2 results now providing confirmation, it looks like the mostly positive interim telaprevir efficacy results from the Prove 1 study were no fluke.

The Prove 2 results will also be released at a medical conference later this year. Phase 3 studies of telaprevir are expected to begin in the fourth quarter of this year, which means investors could start seeing positive results from late-stage studies of the drug toward the end of 2008.

Despite much higher odds of telaprevir making it onto the market following two successful placebo-controlled phase 2 studies, shares of Vertex are trading at 52-week lows. With more clinical trail results coming out later in 2007, this might be the last chance for investors to pick up shares of Vertex so cheaply.

Vertex is a Rule Breakers recommendation, and Johnson & Johnson is an Income Investor selection. You can take either -- or both! -- newsletter for a free 30-day trial.

Fool contributor Brian Lawler does not own shares of any company mentioned in this article. The Fool has a disclosure policy.