Summary: The purpose of this clinical trial is to learn about long-term safety and long-term effects of the study medicine (called ritlecitinib) for the potential treatment of severe alopecia areata, a condition that causes hair loss. This study is seeking participants who have: * previously completed one of Pfizer's pediatric studies for Alopecia Areata (B7981027 or B7981031). * at least 50% scalp hair lo...

Summary: The purpose of the study is to learn about the safety and effects of the study medicine (called ritlecitinib) for the treatment of alopecia areata. Alopecia areata is a disease that causes hair loss on the scalp, face, and areas of the body. Ritlecitinib is approved in many countries at a dose of 50 mg (milligram) taken by mouth once a day for the treatment of patients 12 years and older with seve...

Summary: Keloids are common, benign cutaneous overgrowths that manifest clinically as raised, hypertrophic, often hyperpigmented lesions which are formed in response to dermal injury or idiopathic stimuli. Although keloids are a common disease, it's exact incidence and prevalence is not known. Despite the debilitating nature of keloids, current treatment modalities are limited in efficacy; there is no univ...

Summary: The purpose of this study is to learn about the safety and effects of the study medicine (called ritlecitinib) for the possible treatment of severe alopecia areata. Alopecia areata is a condition that causes hair loss. This study is seeking participants who have: * at least 50% scalp hair loss due to alopecia areata. * received varicella vaccination (2 doses) or have been infected by varicella zos...

Summary: This study is to evaluate how safe and effective ritlecitinib is in participants with non-segmental vitiligo (NSV). Ritlecitinib is studied in patients with non-segmental vitiligo. Vitiligo is a chronic acquired depigmentation disorder characterized by well-defined pale white patches of skin. Non-segmental vitiligo is an autoimmune disorder and is the focus of this study. The study will show: * if...

Summary: Alopecia areata (AA) is a chronic relapsing autoimmune disease characterized by nonscarring hair loss affecting children, adolescents, and adults across all ages, races, and genders. AA primarily affects the scalp; however, it also can affect nails, eyelashes, eyebrows, and other hair follicles on the patient's body. The 3 main types of AA are: * Patchy alopecia (PA), as seen in 90% of clinical di...

Summary: The purpose of this research study is to see if a drug called ritlecitinib is safe and effective for treating chronic spontaneous urticaria (CSU). CSU is hives and itching lasting over six weeks. Ritlecitinib is approved by the Food and Drug Administration (FDA) to treat another condition, but it is not approved for treating CSU. Participation is expected to last 20 weeks and include 7 clinic visi...

Summary: Subjects include: aged 18 to 75 years, inclusive, have biopsy-confirmed disease that is clinically inactive as determined by negative celiac disease (CeD) serology and histology (determined via endoscopy at time of screening), have followed a gluten-free diet (GFD) for ≥6 months as reported by the subject, and be human leukocyte antigen (HLA)-DQ2.5 and/or HLA-DQ8 positive. Study involves the follo...

Summary: The introduction of Janus Kinase inhibitors (JAKi) seems to revolutionize the field of alopecia areata (AA) therapeutics. However, the ideal JAKi is not yet settled and the real-world data are still missing. To provide evidence about effectiveness and safety of different JAKi including tofacitinib, baricitinib, ritlecitinib，abrocitinib, upadacitinib and ifidancitinib in real-world settings and des...