Clinical studies of Ritlecitinib

In a randomized, double-blind, placebo-controlled trial (AA-I trial), the efficacy and safety of Ritlecitinib was evaluated in alopecia areata subjects 12 years and older with ≥50% scalp hair loss (including alopecia totalis (AT) and alopecia universalis (AU)) who were experiencing ongoing episodes of alopecia areata for 6 months to 10 years. The subjects were randomly assigned to a treatment regimen with the recommended dose of ritixitinib 50 mg once daily.

Patients were randomized to receive once-daily ritixitinib (50 mg, 30 mg, or 10 mg), with or without initial treatment with once-daily ritixitinib 200 mg for one month, or to receive once-daily placebo for 24 weeks. At week 24, the ritixitinib arm continued at its assigned dose, and patients initially assigned to placebo were switched to ritixitinib (50 mg or 200 mg loading dose + 50 mg) for an additional 24 weeks. In this pivotal study, there was a statistically significant difference in the proportion of patients treated with ritixitinib 50 mg who achieved scalp hair coverage (salt ≤ 20) of 80% or greater after 6 months of treatment compared with placebo (23% of patients treated with ritixitinib 50 mg vs. 1.6% of patients treated with placebo).

The most common AEs occurring in at least 1% of patients over 24 weeks include headache, diarrhea, acne, rash, urticaria, folliculitis, pyrexia, atopic dermatitis, dizziness, increased serum creatinine phosphokinase, herpes zoster, decreased red blood cell count, and stomatitis. Cases of serious infections, malignancies, thromboembolic events, and laboratory abnormalities have also been reported.