Early On‐Treatment Change in <scp>SALT</scp> as a Pragmatic Predictor of Ritlecitinib Response in Moderate‐To‐Severe Alopecia Areata: A Real‐World Cohort Study

ABSTRACT Background Ritlecitinib, an oral covalent Janus kinase 3 (JAK3)/TEC inhibitor, is now used for alopecia areata (AA), but pragmatic early‐on‐treatment markers to guide continuation decisions are needed. We evaluated whether the Week‐12 (W12) change in Severity of Alopecia Tool (ΔSALT) predicts Week‐24 (W24) response in real‐world care. Methods We conducted a single‐center observational cohort of consecutive patients with moderate‐to‐severe AA treated with ritlecitinib 50 mg once daily. Assessments occurred at baseline (V0, n = 77) and W12 ( n = 55), W24 ( n = 32), W36 ( n = 20), W48 ( n = 11), W60 ( n = 7). The primary endpoint was the proportion achieving SALT ≤ 20 at W24. Secondary endpoints included SALT trajectory, clinician‐reported outcomes (ClinRO) for eyebrows/eyelashes, patient‐reported outcomes (HADS, Skindex‐16), and safety/laboratories. Exploratorily, we tested ΔSALT V0 to W12 as a predictor of W24 response using receiver operating characteristic/area under the curve (ROC/AUC). Results Median SALT declined from 90.0 (V0) to 70.0 (W12) and 30.0 (W24); intra‐individual median ΔSALT vs. baseline was −10.0 at W12 and −45.0 at W24. Responders (SALT ≤ 20) were 18.2% at W12 (10/55) and 43.8% at W24 (14/32). Periocular ClinRO improved by W24 in 54.5% (eyebrows) and 36.4% (eyelashes). Patient‐reported outcomes improved from W12 to W24. Safety was favorable: No serious adverse events or dose modifications were reported; adverse events were mostly mild to moderate (e.g., headache, acne, upper respiratory tract infection [URTI]/nasopharyngitis), and laboratory panels remained stable with modest lipid increases. Early ΔSALT robustly discriminated W24 outcomes: Median −41.0 in future responders vs. +3.0 in non‐responders with an AUC = 0.875. ΔSALT at W12 also predicted sustained response at W48 (AUC 0.83). In multivariable analysis, ΔSALT remained independently associated with W24 response (odds ratio [OR] 1.52 per 10‐point decrease). Conclusions In routine practice, ritlecitinib produced rapid, clinically meaningful improvement with good tolerability. The on‐treatment ΔSALT at 12 weeks is a pragmatic predictor of 24‐week success and supports a treat‐to‐target checkpoint to inform continuation/optimization decisions alongside ClinRO and PROs. image