VX-509: Phase IIa data
Top-line data from the intent-to-treat (ITT; n=204) population of a double-blind, international Phase IIa trial showed that twice-daily 50, 100 and 150 mg oral VX-509 each met the co-primary endpoint of significantly improving ACR20 response rates at week 12 vs. placebo (61%, 65% and 66%, respectively, vs. 29%; p=0.007, p=0.002 and p=0.002). Those 3 doses of VX-509 also met the co-primary endpoint of significantly improving DAS28 scores from baseline to week 12 vs. placebo (2.6, 2.7 and 3.06 points, respectively, vs. 1.25 points; p<0.001 for all). The twice-daily 25 mg dose of VX-509 missed both endpoints (39% and 1.75 points, respectively, p=0.485 and p=0.155).
On secondary endpoints, 50, 100 and 150 mg VX-509 significantly improved ACR50 response rates at week 12 vs. placebo (32%, 38% and 49%, respectively, vs. 7%; p=0.011, p=0.001 and p<0.001), but the 25 mg dose missed the endpoint (17%, p=0.312). The 2 highest doses of VX-509 also significantly improved ACR70 response rates at week 12 vs. placebo (18% and 22%, respectively, vs. 2%; p=0.029 and p=0.014), but the 2 lowest doses missed the endpoint (7% and 12%, respectively, p=0.616 and p=0.201). Additionally, 35% and 37% of patients receiving 100 and 150 mg VX-509 achieved a DAS28 score of <2.6 at week 12 vs. 7% for placebo. In the ITT analysis, patients who discontinued treatment prior to week 12 were counted as non-responders. ...