Vertex RA Study: When Good Is Not Good Enough (VRTX)

Vertex Pharmaceuticals Incorporated (NASDAQ: VRTX) might have sounded as though shares would be up Monday morning if you were just looking at news over the weekend.  Instead, shares are down substantially for a day where stocks are up mildly.

The company showed that the final Phase IIa study results of the investigational selective oral JAK3 inhibitor VX-509 showed substantial and statistically significant improvements in multiple measurements of rheumatoid arthritis activity.

The 12-week study met its two primary endpoints of at least a 20% improvement in the signs and symptoms of RA. For the two highest dose groups of the study, statistically significant ACR20, ACR50, ACR70, and DAS28 responses were also observed as compared to placebo, and more than one-third of people in these groups achieved clinical remission (DAS28 remission). Overall, the most frequently reported class of adverse event in the VX-509 and placebo arms was infections. The data from the study will be presented in a poster session on November 8 at the 2011 Annual Meeting for the American College of Rheumatology in Chicago.

This is not coming to market any time soon as more studies await.  Vertex said that a six-month Phase IIb study of VX-509 in RA is expected to begin in early 2012 to evaluate once-daily and twice-daily in combination with methotrexate with the study covering approximately 350 people with moderate to severe RA.

Additional secondary endpoints were used to evaluate the clinical activity of VX-509, including ACR50 and ACR70 responses at week 12, DAS28 remission and EULAR response. The responses observed in the two highest dose groups for VX-509 indicated continuous and statistically significant improvements in the signs and symptoms of RA, with these effects being observed in some patients as early as the first week of the study.

At least one analyst wanted more.  RBC Capital Markets lowered its rating down to “Sector Perform” from “Outperform” and the new price target was cut to $48 from $49 in the research call.

Vertex shares are down 6.2% at $34.35 after 30 minutes of trading and the 52-week trading range is $32.08 to $58.87.

JON C. OGG