17 September 2018 - - US-based biopharmaceutical company Pfizer Inc. (NYSE: PFE) has released results from its Phase 2a study of PF-06651600, an oral Janus kinase 3 inhibitor, and PF-06700841, a tyrosine kinase 2/JAK1 inhibitor, compared to placebo, in patients with moderate to severe alopecia areata, an autoimmune disease characterised by hair loss and often associated with profound psychological consequences, the company said.

Both JAK inhibitors met the primary efficacy endpoint in improving hair regrowth on the scalp relative to baseline at week 24 (33.6 points and 49.5 points for JAK3 and TYK2/JAK1, respectively) as measured by the Severity of Alopecia Tool score (100 point scale).

The findings were presented during a Late-Breaking News session at the 27th European Academy of Dermatology and Venereology Congress in Paris, France.

Based on the totality of the data and the emerging clinical profiles, the investigational JAK3 inhibitor, which was recently granted Breakthrough Therapy designation from FDA for alopecia areata, is advancing to the next phase of development for moderate to severe AA and will continue to be evaluated for rheumatoid arthritis, Crohn's disease and ulcerative colitis.

PF-06700841 will continue to be evaluated for psoriasis, CD and UC.

This Phase 2a, randomised, double-blind, multicenter study evaluates the efficacy, safety, and tolerability of PF-06651600 and PF-06700841 compared to placebo in patients with moderate to severe AA. Patients were randomized 1: 1: 1 to receive: PF-06651600 (200 mg once daily [QD] for four weeks, followed by 50 mg QD for 20 weeks), or PF-06700841 (60 mg QD for 4 weeks, followed by 30 mg QD for 20 weeks), or placebo.

The study found that the placebo-adjusted mean (95% CI) in SALT change from baseline scores at Week 24 were 33.6 points (21.4, 45.7), (P