A Study of ATI-50002 Topical Solution for the Treatment of Alopecia Areata

Primary:

• To assess safety, tolerability and efficacy of 2 dose strengths of ATI-50002 Topical
Solution, compared to vehicle in subjects with alopecia areata (AA)

Secondary:

• To evaluate key clinical outcome assessments

Inclusion Criteria:

1. Have a clinical diagnosis of alopecia areata (AA) defined as no current areas of
active regrowth, with up to mild (less than 10%) incremental scalp hair loss over the
previous 6 months based on subject history.

2. Have a Severity of Alopecia Tool (SALT) score of at least 30% up to 95% total scalp
hair loss determined by the study investigator at baseline.

3. Have a duration of the current episode of scalp hair loss of a minimum of 6 months and
a maximum of seven years.

4. If a woman of childbearing potential (WOCBP), must have a negative serum pregnancy
test at Screening (Visit 1) and a negative urine pregnancy test at Baseline (Visit 2)
and agree to: use a highly effective method of birth control for the duration of the
study; not be planning a pregnancy during the study duration and use contraception for
30 days after last application of study medication.

Exclusion Criteria:

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

2. Diffuse alopecia areata or a history of an atypical pattern of AA (e.g., ophiasis,
sisaihpo).

3. Concomitant hair loss disorder (by history or physical exam) such as androgenetic
alopecia or scarring alopecia (e.g., cicatricial alopecia, frontal fibrosing alopecia,
etc.).

4. 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.

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

6. 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.