Safety and Pharmacokinetic Study of ATI-50002 in Subjects With Alopecia Universalis (AU) and Alopecia Totalis (AT)

This study is designed to evaluate the safety, tolerability, pharmacokinetics and
pharmacodynamics of ATI-50002 Topical Solution in patients with Alopecia Universalis and
Alopecia Totalis. Concentrations of ATI-50002 in the blood and skin will be assessed after 28
days of treatment with ATI-50002 Topical Solution.

Inclusion Criteria:

- Able to comprehend and willing to sign an Informed Consent Form (ICF).

- Male or non-pregnant, non-nursing female ≥18 years old at the time of informed
consent.

- Have a clinical diagnosis of stable, clinically typical, AU or AT.

- Have a duration of the current episode of AU or AT for a minimum of 6 months and a
maximum of seven years.

- Be willing and able to follow all study instructions and to attend all study visits.

Exclusion Criteria:

- Females who are nursing, pregnant, or planning to become pregnant for the duration of
the study including 30 days after the last application of study medication.

- Patchy alopecia areata, diffuse alopecia areata or a history of an atypical pattern of
Alopecia Areata (AA) (e.g., ophiasis, sisaihpo).

- Active skin disease on the scalp (such as psoriasis or seborrheic dermatitis) or a
history of skin disease on the scalp that in the opinion of the investigator would
interfere with the study assessments of efficacy or safety.

- Active scalp trauma or other condition affecting the scalp that, in the investigator's
opinion, may affect the course of AU or AT or interfere with the study conduct or
evaluations.

- The presence of a permanent or difficult to remove hairpiece or wig that will, in the
opinion of the investigator, interfere with study assessments if not removed at each
visit.