A Long-Term Study to Learn About The Study Medicine Called Ritlecitinib in Children With Severe Alopecia Areata.

California Dermatology & Clinical Research Institute, Encinitas, California, United States

Pediatric Skin Research, Miami, Florida, United States

D&H Tamarac Research Center, Tamarac, Florida, United States

Dawes Fretzin Clinical Research Group, LLC, Indianapolis, Indiana, United States

Kindred Hair and Skin Center, Marriottsville, Maryland, United States

Michigan Dermatology Institute, Waterford, Michigan, United States

Ear, Nose & Throat Consultants, LLC, Omaha, Nebraska, United States

Skin Specialists, PC dba Schlessinger MD, Omaha, Nebraska, United States

Complete Behavior Health (Dr. Brittany Marshall, Licensed Psychologist), Papillion, Nebraska, United States

University of New Mexico Health Sciences Center, Albuquerque, New Mexico, United States

University of New Mexico-IDS Pharmacy, Albuquerque, New Mexico, United States

Regents of the University of New Mexico, Albuquerque, New Mexico, United States

Equity Medical, LLC, The Bronx, New York, United States

Northwest Dermatology Institute, Portland, Oregon, United States

Penn State Health Milton S. Hershey Medical Center, Hershey, Pennsylvania, United States

Medical University of South Carolina Department of Dermatology and Dermatologic Surgery, Charleston, South Carolina, United States

3A Research, El Paso, Texas, United States

Texas Dermatology and Laser Specialists, San Antonio, Texas, United States

Huashan Hospital, Fudan University, Shanghai, Shanghai Municipality, China

Prof. MUDr. Petr Arenberger, DrSc., MBA, Prague, Czechia

Hospices Civils de Lyon - Hopital Femme Mere Enfant, Bron, France

CHU de Dijon Bourgogne, Dijon, France

GHICL - Service d'investigation - Recherche clinique, Lille, France

Hôpital Saint Vincent de Paul, Lille, France

Centre Hospitalier Universitaire de Nice, Nice, France

Hôpitaux Drôme Nord, Romans-sur-Isère, France

Centre Hospitalier Universitaire de Toulouse - Hôpital Larrey, Toulouse, France

Tohoku University Hospital, Sendai, Miyagi, Japan

Hamamatsu University Hospital, Hamamatsu, Shizuoka, Japan

Kyorin University Hospital, Mitaka, Tokyo, Japan

Osaka Metropolitan University Hospital, Osaka, Japan

Cityclinic Przychodnia Lekarsko-Psychologiczna Matusiak Spółka Partnerska, Wroclaw, Lower Silesian Voivodeship, Poland

DERMEDIC Iwona Zdybska, Lublin, Lublin Voivodeship, Poland

Klinika Osipowicz & Turkowski, Warsaw, Masovian Voivodeship, Poland

Państwowy Instytut Medyczny MSWiA, Warsaw, Masovian Voivodeship, Poland

Provita Poliklinika, Warsaw, Masovian Voivodeship, Poland

Klinika Ambroziak Dermatologia, Warsaw, Masovian Voivodeship, Poland

Royalderm Agnieszka Nawrocka, Warsaw, Masovian Voivodeship, Poland

Centrum Medyczne Angelius Provita, Katowice, Silesian Voivodeship, Poland

Uniwersytecki Szpital kliniczny im. F. Chopina w Rzeszowie, Rzeszów, Poland

Dermoklinika - Centrum Medyczne spółka cywilna M. Kierstan, J. Narbutt, A. Lesiak, Lodz, Łódź Voivodeship, Poland