Phase II Clinical Study of VC005 Tablets in Subjects With Severe Alopecia Areata

Inclusion Criteria: * Subjects must fully understand the study, be willing and able to comply with all trial procedures, voluntarily participate in the clinical trial, and provide written informed consent by signing the informed consent form (ICF). * Subjects must be aged between 18 and 65 years (inclusive) at the time of ICF signing, regardless of gender. * Subjects must meet the diagnostic criteria for alopecia areata (AA) at both screening and baseline visits. Exclusion Criteria: * Women who are pregnant or breastfeeding, or subjects who plan to become pregnant or breastfeed during the study period. * Subjects with a current diagnosis of acute diffuse alopecia areata (AA). * Subjects with a current diagnosis of other types of alopecia that may interfere with the evaluation of AA, including but not limited to traction alopecia, cicatricial alopecia, telogen effluvium, androgenetic alopecia, syphilitic alopecia, anagen effluvium, folliculotropic mycosis fungoides, or alopecia caused by thyroid disease, etc. * Subjects with other scalp diseases that may affect the assessment of AA, such as scalp psoriasis, dermatitis, tinea capitis, etc.