Randomized, Double-Blind, Placebo-Controlled Phase 2a, Proof-of-Concept Trial of ADX-914 Phase 2a Trial for the Treatment of Severe Alopecia Areata (SIGNAL-AA)

Key Inclusion Criteria: Age 18 to 75 years, inclusive, at time of informed consent, with severe AA (duration of current episode of hair loss >6 months and <10 years) Moderate to severe disease activity at baseline and screening defined as: SALT score ≥ 50% Key Exclusion Criteria: Body weight <48 kg or >105 kg at screening. Active forms of other inflammatory skin disease(s) or evidence of other skin conditions (eg, psoriasis, seborrheic dermatitis, lupus) at the time of screening and through Day 1 that, in the opinion of the investigator, may interfere with evaluation of AA and the assessment of the disease activity measures History of or diagnosis at screening of another form of alopecia based on assessment by investigator (except for androgenic alopecia). History of male or female pattern hair loss of Hamilton stage >III or Ludwig stage >II. History (lifetime) or presence of hair transplants. History (lifetime) or presence of micropigmentation of the scalp (Note: Microblading of the eyebrows is permitted). Use of systemic, topical, or device-based therapy for AA. History of, recent, or current clinically serious viral, bacterial, fungal, or parasitic infection or mycobacterial infection or at risk of serious infection. A positive QuantiFERON®TB Gold test at Screening or history of tuberculosis (TB)