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Updated: Jan 15, 2026

A New Technique for Quantitative Analysis of Hair Loss in Mice Using Grayscale Analysis
Published on: March 9, 2015
Improvement in Patient-Reported Emotional Symptoms and Activity Limitations due to Hair Loss in Patients With
Ernest H Law1, Bintu Sherif2, Arash Mostaghimi3
1Pfizer, Inc., New York, New York, USA.
Background:
Patients with alopecia areata (AA) in ALLEGRO-2b/3 (NCT03732807) had clinically significant hair regrowth and patient-reported improvements with ritlecitinib versus placebo, but patient-reported improvements in AA Patient Priority Outcomes (AAPPO) emotional symptoms (ES) or activity limitations (AL) were not observed during the 24-week placebo-controlled phase. This study compared AAPPO scores between the 50-mg ritlecitinib maintenance dose (+/- 200-mg 4-week loading dose) and subtherapeutic 10-mg ritlecitinib through Week 48 of ALLEGRO-2b/3.
Methods:
Least squares mean (LSM) changes from baseline (CFBs) in domain scores were estimated for the full analysis population and for participants with baseline domain scores ≥ 1. Item-level responses (scores < 2) were evaluated for participants with baseline item scores ≥ 2, since lower baseline item scores (measured on 5-point response scales; range, 0-4) indicated less frequent/severe impacts from hair loss.
Results:
There were 325 participants (200/50-mg [n = 132] and 50-mg [n = 130], combined and as subgroups; 10-mg [n = 63]). LSM CFBs in ES and AL domain scores generally improved through Week 48 for all 50-mg groups, with significant differences versus 10-mg starting at Week 34 for ES and Week 40 for AL. The proportion of responders for all ES and AL items generally increased through Week 48 for all 50-mg groups. The largest improvements versus 10-mg were for ES items 5 and 6 (self-consciousness and embarrassment) and AL item 11 (interactions with others).
Conclusions:
ALLEGRO-2b/3 participants reported greater improvements in ES and AL due to hair loss by Week 48 with the 50-mg ritlecitinib maintenance dose (+/- 200-mg loading dose) versus subtherapeutic 10-mg ritlecitinib.

