Positive Top-Line Results Announced from Clinical Trial of Ritlecitinib in Alopecia Areata

Positive results were announced from the phase 2b/3 ALLEGRO trial evaluating oral once-daily ritlecitinib in patients with alopecia areata, which is an autoimmune disease driven by an immune attack on the hair follicles that causes hair loss on the scalp and can affect the face and body, according to the press release.

In the study, ritlecitinib 50 mg and 30 mg achieved the primary efficacy endpoint, specifically the proportion of patients with less than or equal to 20% scalp hair loss after 6 months of treatment versus placebo.

“We are pleased by these positive results for ritlecitinib in patients with alopecia areata, a devastating and complex autoimmune disease for which there are currently no US Food and Drug Administration (FDA)- or European Medicines Agency-approved treatments,” said Michael Corbo, PhD, Pfizer chief development officer, Inflammation & Immunology, in a press release. “We look forward to bringing this potential new treatment option to patients living with alopecia areata as soon as possible.”

The ALLEGRO trial met the primary efficacy endpoint of improving scalp hair regrowth, in which all participants joining the study with at least 50% scalp hair loss due to alopecia areata as measured by the Severity of Alopecia Tool score. A greater proportion of patients who took ritlecitinib 30 mg or 50 mg once-daily, with or without a 4-week initial treatment of 200 mg once-daily, had 20% or less scalp hair loss after 24 weeks of treatment compared with placebo, according to the press release.

During a 24-week extension period, all participants who were randomized to receive ritlecitinib continued on the same regimen, whereas participants who received placebo during the initial 24 weeks advanced to 1 of 2 regimens: 200 mg for 4 weeks followed by 50 mg for 20 weeks, or 50 mg for 24 weeks. Additionally, the study included a 10 mg dosing arm, which was measured for dose-ranging and was not tested for statistically significant efficacy compared to placebo.

The percentage of patients with adverse events (AEs), serious AEs, and discontinuing due to AEs was similar across all treatment groups. Nasopharyngitis, headache, and upper respiratory tract infection were the most common AEs, with no major adverse cardiac events, deaths, or opportunistic infections in the trial. Mild to moderate herpes zoster developed in 8 patients who were treated with ritlecitinib, with 1 case of pulmonary embolism in the ritlecitinib 50 mg group, according to the press release.

Ritlecitinib, which is also being evaluated for vitiligo, rheumatoid arthritis, Crohn disease, and ulcerative colitis, was granted Breakthrough Therapy designation from the FDA for the treatment of alopecia areata in September 2018.

REFERENCE

Pfizer announces positive top-line results from phase 2b/3 trial of ritlecitinib in alopecia areata. Pfizer. August 4, 2021. Accessed August 4, 2021. https://www.pfizer.com/news/press-release/press-release-detail/pfizer-announces-positive-top-line-results-phase-2b3-trial