A Safety and Tolerability Study of KD025 Treatment in Subjects With Moderately Severe Psoriasis Vulgaris

Inclusion Criteria:

- Diagnosis of moderately severe plaque psoriasis that has been stable for 6 months and
has failed at least one line of systemic therapy and is a candidate for additional
systemic therapy.

- Had a PASI of ≥12

- At least 10% of body surface area that is affected by plaque psoriasis.

- Willing to avoid tanning devices or sun bathing.

- Willing to forgo systemic and topical treatments for psoriasis during the course of
the study.

- Adequate bone marrow function

- Negative urine pregnancy test (for women of childbearing potential)

- Agree to use a highly effective method of birth control (< 1% per year failure rate)
during the study and for 1 month after the termination of the study.

- Willing to complete all study measurements and assessments in compliance with the
protocol.

Exclusion Criteria:

- Non-plaque or drug-induced psoriasis

- Currently using corticosteroid or immunosuppressive therapy except for Class 5 or
weaker topical corticosteroids to the face, groin, or scalp

- Using any topical therapy except for the following:

1. Class 5 or weaker steroids and phototherapy for 4 weeks prior to study entry

2. Immunosuppressive therapies for 4 weeks prior to study entry

3. Methotrexate, acitretin, or cyclosporine for 4 weeks prior to study entry

4. Biologic therapies for 3 months prior to study entry.

- Concomitant condition requiring treatment with moderate to high dose steroids in the
12 weeks prior to screening.

- Viral, fungal, or bacterial skin infection.

- Pregnant or lactating woman.

- Currently participating in another study with an investigational drug or within 28
days of study entry

- History or other evidence of severe illness or any other conditions that would make
the subject, in the opinion of the investigator, unsuitable for the study

- History or presence of any of the following:

1. Hepatic disease and or alanine aminotransferase (ALT) or aspartate
aminotransferase (AST) > 1.5 × the upper limit of normal (ULN) at screening

2. Renal disease and/or serum creatinine > 1.5xULN at screening

- Has QTc(f) intervals of > 450 msec at the screening or pre-dose ECG

- Subject is receiving any drugs known to prolong the QTc interval, including any
anti-arrhythmic medications within 2 weeks prior to screening

- Subject is receiving any drug that is a strong CYP enzyme inhibitor

- Subject is receiving any concomitant systemic drug that is metabolized by CYP enzyme

- Previous exposure to KD025 or known allergy/sensitivity to KD025 or any other ROCK-2
inhibitor.