A Study to Learn About Litfulo Capsule in People With Severe Alopecia Areata in Routine Clinical Practice.

The purpose of this observation study is to learn about the safety and effects of the study medicine (called Litfulo) for the potential treatment of Severe Alopecia Areata.

To evaluate the safety of Litfulo Capsule after marketing, with regard to the following clauses in routine clinical practice. * Adverse Events (AEs)/ Adverse Drug Reactions (ADRs) * Unexpected Adverse Events (AEs)/ADRs that have not been reflected in the approved drug label * Serious Adverse Events (SAEs)/Serious Adverse Drug Reaction (SADRs) * Adverse Event of Special Interest(AESI) * Serious Infections, defined as any infection (viral, bacterial, and fungal) requiring parenteral antimicrobial therapy or hospitalization for treatment or meeting other criteria that require the infection to be classified as serious adverse event * Opportunistic infections and Herpes Zoster * Malignancy