Ritlecitinib, brepocitinib show promise against scalp alopecia areata
Ritlecitinib and brepocitinib lead to improvements in scalp alopecia areata and its associated biomarkers, reveals a recent substudy of a phase 2a trial.
Drawing from a previous randomized, double-blind, placebo-controlled trial, the present analysis looked at 48 patients who had been given ritlecitinib (n=18), brepocitinib (n=16), or placebo (n=12). Lesional scalp biopsies were conducted to measure change in biomarker levels. The correlation of such biomarkers with hair regrowth, as measured by the Severity of Alopecia Tool (SALT), was also assessed.
Ritlecitinib and brepocitinib were both strongly effective, resulting in >100-percent improvements in the lesional scalp profiles from baseline. At week 12, for example, brepocitinib induced a 114.69-percent improvement in lesional profile, significantly greater than the 61.61-percent impact of ritlecitinib (p<0.001).
By week 24, however, ritlecitinib had eclipsed brepocitinib, inducing a 162.23-percent vs 103.8-percent improvement, respectively (p<0.001). Nevertheless, researchers said that these findings indicate that immune abnormalities in the scalp were effectively suppressed by both active treatments.
In turn, improvements in inflammatory skin biomarkers correlated significantly with a better serum biomarker profile, as well as with more favourable SALT scores. For instance, at week 12 clinical improvement was associated with lower type 1 and 2 helper T cells, and higher keratin levels.
Meanwhile, at week 24, lower SALT scores were correlated with suppressed type 2 helper T cells, CD3 T cells, and interleukin-9 concentrations.
“Because the changes in molecular biomarkers occurred between weeks 12 and 24, it would be of interest to assess whether additional changes occur after 24 weeks. Larger, long-term clinical trials are warranted to evaluate dosage, duration of therapy, safety, and efficacy,” the researchers said.