Clinical Data
In Phase 1, CTP-543 was well tolerated across all dose groups and there were no serious adverse events reported in the study. The most common reported adverse event was headache. There were no withdrawals or dose modifications related to CTP-543 in the trial.In the trial, CTP-543 showed increased exposure with increasing doses. The safety and exposure observed with 16 mg of CTP-543 twice daily appeared to be comparable to published findings for the reported exposure of 20 mg ruxolitinib twice daily. CTP-543 had a half-life of approximately 3.3 hours, similar to that reported for non-deuterated ruxolitinib1. In an open-label clinical trial of 12 patients with moderate-to-severe alopecia areata, investigators at Columbia University reported that 20 mg of ruxolitinib administered orally twice daily resulted in significant hair regrowth in 75% of the patients2. Given the overall exposure and safety parameters observed with CTP 543 in the Phase 1 program, the Company has selected four doses (4, 8, 12 and 16 mg twice daily) to evaluate in its double-blind, placebo-controlled Phase 2a trial.