Study to Evaluate Long-Term Safety of ASN002 in Subjects With Moderate to Severe Atopic Dermatitis

This is a randomized open label study where subjects with moderate to severe atopic
dermatitis will roll over from the Phase 1 ASN002AD-101 and ASN002AD-201 Ph2b study and be
randomized to receive ASN002 at 40mg, 60mg, or 80mg once daily for up to 24 months. This
study will also characterize the pharmacokinetics of ASN002 through blood sampling from
subjects who consent.

Inclusion Criteria

- Subject with a history of moderate to severe atopic dermatitis who participated in the
preceding ASN002AD-201 and ASN002AD-101 study

- Subject must be a candidate for prolonged open label ASN002 treatment according to the
investigator's judgment.

- Subject has been using an emollient daily for at least 1 week prior to Day 1 and
agrees to continue using that same emollient daily throughout the study.

- Men and women participating in the study must use medically acceptable birth control
or total abstinence from sexual intercourse

- Subject is willing to participate and is capable of giving informed consent. Note:
Consent must be obtained prior to any study-related procedures.

- Subjects must be willing to comply with all study procedures and must be available for
the duration of the study.

- Subject must be a candidate for prolonged open label ASN002 treatment according to the
investigator's judgment.

- Subject has a body mass index (BMI) ≤ 35 kg/m2.

Exclusion Criteria

- Subject is a female who is breastfeeding, pregnant, or who is planning to become
pregnant during the study.

- Subject has clinically infected atopic dermatitis.

- A serious uncontrolled condition including hypertension, history of tuberculosis,
hepatitis B or C infection, immune deficiency, heart disease, heart conduction
disorder, diverticulitis, diabetes, reflux disease requiring protocol pump inhibitor
therapy, malabsorption syndrome, or cancer

- Subject has a history of skin disease or presence of skin condition that, in the
opinion of the investigator, would interfere with the study assessments.

- Subject has a history of eczema herpeticum within 12 months, and/or a history of 2 or
more episodes of eczema herpeticum in the past.

- Willing to comply with discontinuation of certain treatments for AD, as directed by
the Investigator.