Nearly half regained most scalp hair on a second JAK inhibitor
JAK inhibitors are pills that can regrow hair in severe alopecia areata. Not every patient responds to the first one. This study looked at how patients do after switching to a different JAK inhibitor.
Dr. Senna and colleagues worked with hair specialists at several US centers. Together they looked back at the records of 108 patients with severe alopecia areata. Each patient took one JAK inhibitor for at least 6 months and then switched to another. Hair loss was scored with the SALT scale, which measures the percent of the scalp without hair.
On the second JAK inhibitor, 48.8% of patients with full follow-up data reached a SALT score of 20 or less. That means no more than 20% of the scalp was bare. And 32.6% reached a SALT score of 10 or less. Of 21 patients who moved on to a third JAK inhibitor, 52.4% reached SALT 20 or less. Patients who responded to the first drug were more likely to respond to the second (odds ratio 3.33). Side effects were mild.
This study looked back at existing records. It can show patterns but cannot prove cause. Treatments varied from patient to patient. The patients who switched may also differ from those who did not. Still, the results suggest a second JAK inhibitor can be a reasonable option to discuss with a dermatologist.
Martin A, Chen LC, Kreytak C, et al. Switching between Janus kinase inhibitors for treatment of alopecia areata: a multicenter retrospective review. J Am Acad Dermatol. 2026;94(6):1662-1670.
