Prospective observational registry focusing on an adolescent cohort diagnosed with severe alopecia areata,receiving routine care from dermatology providers. Visit schedules for patients will be determined by the provider in accordance with routine clinical care, and any prescriptions provided to patients will adhere to product availability and local prescribing guidelines/regulations in the country where the participating registry site is located.

The objective of the registry is to create a cohort of adolescent subjects to evaluate the long-term real-world safety and effectiveness of routine clinical care of treatments for severe AA. Data collected through the registry may be used to address a range of research questions and use cases including, but not limited to: better characterizing the natural history of the disease, evaluating the effectiveness and safety of commercially available medications for the treatment of severe AA in adolescents, providing information to support characterization of adolescent growth and development and ongoing risk-benefit evaluation by drug manufacturers and regulators, and research related to drug utilization, disease burden, and unmet needs. Further, data collected may be used to generate real world evidence to inform clinical decision making by patients and treating providers.

This will be enabled through standardized data collection including validated instruments for patient-reported outcomes (PROs) and clinician-reported outcomes (ClinROs), the active evaluation of prevalent and incident comorbidities and adverse events, and the recording of medication utilization data.

Inclusion Criteria:

To be eligible to participate in this registry, an individual must meet all the following criteria:

1. Has ever been diagnosed with severe AA by a dermatologist or a qualified dermatology provider.
2. Is 12-17 years of age at the time of enrollment.
3. Is willing to provide consent/assent for participation in the registry.
4. Has been prescribed a new commercially available advanced therapy and/or conventional systemic therapy for the treatment of severe AA in adolescents in the context of routine clinical care that is consistent with local prescribing guidelines and/or regulations for the country where the site is located.

A new therapy is a medication that the subject has never taken before.

1. At the time of registry enrollment OR
2. Within 6 months prior to registry enrollment In the opinion of the treating provider, is deemed a candidate for treatment with a commercially available advanced therapy and/or conventional systemic therapy for the treatment of severe AA in adolescents but has not received nor is planning to initiate treatment at the time of registry enrollment.

Exclusion Criteria:

An individual who meets any of the following criteria will be excluded from participation in the registry:

1. Is participating or planning to participate in a blinded clinical trial for any investigational medication.
2. Is unwilling or unable to provide standing height measurements.

Subjects can enroll as early as age 12 and will be followed until the age of 18; therefore, the maximum duration a subject can be enrolled is 6 years.