[1]
National Alopecia Areata Foundation prevalence estimates, cross-referenced with FDA drug-approval program materials; commonly cited range of 700,000 to 2 million Americans with active alopecia areata at any given time.
[2]
Ritlecitinib (LITFULO) in Alopecia Areata National Drug Monograph, U.S. Department of Veterans Affairs, 2023. Ritlecitinib and baricitinib are the two FDA-approved oral JAK inhibitors for severe alopecia areata, both approved since 2022.
[3]
Patterns of clinical response in patients with alopecia areata treated with ritlecitinib in the ALLEGRO clinical development programme. PMC, 2025. Of 191 patients treated with ritlecitinib 50mg: 45.5% were SALT ≤20 responders, 12.6% partial responders, 12.6% relapsers, 29.3% non-responders through Month 24.
[4]
A Cost-per-Responder Analysis of Ritlecitinib vs Baricitinib in Severe Alopecia Areata.
Journal of Health Economics and Outcomes Research, 2026. Cost modeling based on U.S. wholesale acquisition costs for once-daily ritlecitinib 50mg and baricitinib 2mg/4mg over a 1-year time horizon.
[5]
Long-term safety and efficacy of ritlecitinib in adults and adolescents with alopecia areata (ALLEGRO-LT). PMC, 2025. At Month 24, 73.5% and 66.4% of patients achieved SALT ≤20 and ≤10 respectively; mean exposure was 728.7 days, indicating extended treatment duration is typical.
[6]
Cost-Effectiveness Analysis of Ritlecitinib Compared With No Treatment in Patients With Severe Alopecia Areata in Japan. PMC, 2025. Real-world JAK inhibitor discontinuation/retention benchmarks cited from rheumatoid arthritis literature: ~50% retention at 4 years (Spain), ~70% discontinuation within 12 months in some Japanese cohorts, primarily due to non-response.
[7]
Same ALLEGRO patterns-of-response study (PMC12105426): full response-category breakdown through Month 24, including sustained response and complete response rates among responders.
[8]
A Cost Per Responder Analysis of Ritlecitinib and Baricitinib, ISPOR 2025 poster. Decision-tree cost modeling explicitly built around the fact that a substantial share of initiators on either drug do not reach a meaningful SALT response, making cost-per-responder a materially different (and higher) figure than list price alone.
[9]
Ritlecitinib for treating severe alopecia areata in people 12 years and over. NICE/NCBI Bookshelf technology appraisal, 2024. Patient experts described living with severe alopecia areata as having “a profound impact on psychosocial health.”