RA PHARMACEUTICALS,INC. (NASDAQ:RARX) Files An 8-K Other EventsItem 8.01. Other Events.
On December10, 2018, Ra Pharmaceuticals,Inc. (the “Company”) announced positive topline results from its Phase 2 clinical trial evaluating zilucoplan for the treatment of generalized myasthenia gravis, or gMG. The Phase 2, multi-center, randomized, double-blind, placebo-controlled trial was designed to evaluate the safety, tolerability, and preliminary efficacy of zilucoplan in patients with gMG, regardless of prior therapies, who had a Myasthenia Gravis Foundation of America, or MGFA, Disease Classof II-IVa at screening and a Quantitative Myasthenia Gravis, or QMG, score of at least 12 at screening and randomization.
The Company enrolled a total of 44 patients in the Phase 2 clinical program in the United States and Canada. At the outset of the 12-week treatment period, patients were randomized in a 1:1:1 ratio to receive daily, SC doses of 0.1 mg/kg of zilucoplan, 0.3 mg/kg of zilucoplan, or matching placebo. All 44 patients completed the 12-week study and, of these, 43, or 98%, elected to enter a long-term extension to receive active study drug, with one patient in the placebo group not entering the extension. The diagram below summarizes the Phase 2 trial design:
Figure 1. Summary of Phase 2 Clinical Program
The pre-specified primary efficacy endpoint was the change in QMG score, a physician-administered assessment of MG-related muscle weakness, from baseline to week 12. The key secondary efficacy endpoint was the change in MG Activities of Daily Living, orMG-ADL, score, a patient-reported outcome measure, from baseline to week 12. Significance testing was pre-specified at a 1-sided alpha of 0.1.
Zilucoplan achieved clinically meaningful and statistically significant reductions in both the primary and key secondary endpoints for both zilucoplan dose groups tested versus placebo at 12 weeks. Zilucoplan dosed at 0.3 mg/kg SC daily achieved a mean reduction from baseline of 6.0 points in the QMG score (placebo-corrected change = -2.8; p=0.05), and a mean reduction from baseline of 3.4 points in the MG-ADL score (placebo-corrected change = -2.3; p=0.04), in each case resulting in a clinically meaningful and statistically significant improvement over placebo, as shown in the figures below.