Concert Pharma recently released the results of its phase II clinical trial evaluating the dose range of the experimental deuterated CTP-543 for patients with moderate to severe alopecia areata, an autoimmune disease that results in partial or complete hair loss. The main efficacy endpoints were reached in the 2mg/d and 12mg/d cohort.
The double-blind, randomized, placebo-controlled, sequential dose study was conducted in adults with moderate to severe alopecia areata to assess the efficacy and safety of CTP-543. 149 patients were randomized to receive one of three doses of CTP-543 (4 mg, 8 mg, 12 mg) or placebo twice daily. The primary end point of the study was the proportion of respondents at week 24 of treatment, defined as a reduction in the SALT score of ≥50% relative to baseline. In this study, the patient enrollment criteria were SALT for at least 50%, and all patients had an average SALT score of approximately 88%, with 0% indicating no scalp alopecia and 100% indicating complete scalp alopecia. All patients who completed 24 weeks of treatment in the 12 mg cohort had the opportunity to continue into a separate extended study to assess the long-term safety and efficacy of CTP-543.
This study achieved the primary efficacy endpoint: at the 24th week of treatment, there was a significantly higher proportion of patients with a significantly higher SALT total score of ≥50% relative to baseline in the 12 mg cohort and the 8 mg cohort compared with the placebo group. The specific data are: The proportion of patients who reached the primary endpoint in the 12 mg cohort and the 8 mg cohort was 58%, 47%, and 9% in the placebo group (p < 0.001). 21% of patients in the 4 mg cohort reached the primary endpoint, but there was no significant difference compared to the placebo group. In addition, at week 24, a significantly higher proportion of patients with a significantly higher proportion of SALT in the 12 mg cohort and the 8 mg cohort decreased ≥75% and ≥90% from baseline compared with the placebo group.
At week 24, patients receiving 12 mg and 8 mg doses of the CTP-543 also achieved significantly greater improvement in alopecia areata as assessed by the Patient Global Impression of Improvement Scale compared with the placebo group. Data: 78%, 58% of patients in the 12 mg cohort and 8 mg cohort were assessed as “much improved” or “very much improved”, with significant differences compared with placebo.
Figure 1 CTP-543 treatment of alopecia areata
Dr. James V. Cassella, Chief Development Officer of Concert Pharma, said that “we are very satisfied with these clinical results and continue to believe that CTP-543 has the potential to be the best treatment for alopecia areata. Dr. Brett King, associate professor of dermatology at Yale University School of Medicine, said: “The results of a phase II study of CTP-543 (a JAK inhibitor) in patients with alopecia areata are very encouraging. More and more evidence supported JAK as a target for the treatment of alopecia areata. This has prompted the dermatology community to be passionate about addressing the important needs of patients who are not satisfied.”
CTP-543 was discovered by applying Concert’s deuterium chemical technique to modify ruxolitinib, a selective Janus kinase 1 and Janus kinase 2 (JAK1/JAK2) inhibitor, which is licensed in the United States under the brand name Jakafi to treat certain blood disorders. Ruxolitinib’s deuterium chemical modification can alter its pharmacokinetics in humans, enhancing its use as a treatment for alopecia alopecia. FDA has granted CTP-543 a rapid pathway status in the treatment of alopecia areata, and listed alopecia areata as one of the eight major new disease areas of its focus in the 2016-2017 Patient-Centric Drug Development Program (FFDDI).
References
1.Concert Pharmaceuticals Reports Positive CTP-543 Results from Phase 2 Alopecia Areata Trial