Changes in Hair Color, Skin Pigmentation
As for safety, during the first 16 weeks, 66% of those on active treatment and 39% on placebo experienced at least one adverse event. There were no treatment-related serious adverse events, compared with two among those who received treatment for the full 52 weeks.
The most common adverse events with active treatment were hair color changes (14% in the first 16 weeks and 26% among those treated for the full 52 weeks), neutropenia/reduced neutrophil count (9% in the first 16 weeks and 17% among those treated for the full 52 weeks), and skin hypopigmentation (1% in the first 16 weeks, 13% among those treated for the full 52 weeks, and 19% among those who switched from placebo to active treatment at 36 weeks). Urticaria was reported by 10% among patients on active treatment and 10% among those on placebo in the first 16 weeks, and by 15% of those treated for the full 52 weeks.
In the post-presentation discussion, Metz explained that the hypopigmentation appears to start around the hair follicle and is diffuse, so tends to look like vitiligo.
He suggested that the melanocytes around the hair follicle “seem to be the ones that are more stressed, maybe because of the hair follicle cycling,” adding that the effect is reversible and does not appear to be dose dependent.
The study was funded by Celldex Therapeutics. Metz declared relationships with AbbVie, ALK-Abelló, Almirall, Amgen, argenx, AstraZeneca, Astria, Attovia Therapeutics, Celldex, Celltrion, Escient Pharmaceuticals, Galen, Galderma, GSK, Incyte, Jasper, Lilly, Novartis, Pfizer, Pharvaris, Regeneron, Sanofi, Teva, Third Harmonic Bio, and Vifor.
A version of this article first appeared on Medscape.com.