The purpose of this study is to evaluate the safety and efficacy of AN2728 Ointment, 5%, compared to Ointment Vehicle, applied twice daily for 12 weeks, in the treatment of plaque type psoriasis

This is a single center, randomized, double-blind, vehicle-controlled, bilateral design. Patients will apply both test articles, AN2728 Ointment, 5%, and Ointment Vehicle twice daily for 12 weeks. The assigned study medication will be applied to two comparable treatment targeted plaques identified at baseline. One test article will be applied to one plaque and the other test article to an anatomically distinct plaque. All efficacy evaluations will be measured from only the two plaques identified at the baseline visit.

Inclusion Criteria:

1. Male or female >18 years of age at time of enrollment

2. The clinical diagnosis of stable plaque psoriasis

3. Two target plaques of similar severity

   • ≥ 5 cm2 but ≤ 100 cm2 computed by multiplying the greatest diameter of the plaque by the diameter of the plaque perpendicular to the greatest diameter
   • Bilaterally located (right/left) plaques on the arms or distinct plaques located on the trunk. Plaques located on the trunk must be separated by at least 10 cm and will be designated by the Investigator as either left/right or front/back or upper/lower
   • Overall target plaque severity score (OTPSS) of 2-4 (mild to moderate) with no more than a 1 point difference in the scores of the individual plaques

4. Normal or not clinically significant screening laboratory results

5. Willing and able to apply study drug as directed, comply with study instructions and commit to all follow-up visits

6. Ability to understand, agree to and sign the study Informed Consent Form (ICF) prior to initiation of any protocol related procedures

Exclusion Criteria:

1. Any dermatological conditions that could interfere with clinical evaluations or any disease state or physical condition which might expose the patient to an unacceptable risk by study participation

2. Any underlying disease(s) or other dermatological conditions that require the use of exclusionary topical or systemic therapy (see below).

3. Known sensitivity to any of the components of the study medication

4. Spontaneously improving or rapidly deteriorating psoriatic plaques or pustular/exfoliative, guttate, erythrodermic or other non-plaque form of psoriasis

5. Concomitant use of topical or systemic therapies that might alter the course of psoriasis

6. Females of child bearing potential. Females must be post-menopausal or surgically sterile (oophorectomy).

7. Washout periods of:

   • Topical drugs that might alter the course of psoriasis: 2 weeks
   • Oral retinoids: 8 weeks
   • Non-retinoid systemic drugs that might alter the course of psoriasis: 4 weeks
   • PUVA: 4 weeks
   • UVB therapy: 4 weeks
   • Use of emollients/moisturizers on area(s) to be treated: 2 days to baseline visit

8. AIDS or AIDS related illness

9. Concurrent participation in another drug research study or within 30 days of enrollment

10. Use of lithium or hydroxychloroquine containing products (i.e. Plaquenil)

11. Use of a beta-blocking medication (i.e. propranolol) if the dose has not been stabilized for at least 3 months

Intent-to-treat (ITT) population included all randomized participants who received the study medication.

Same event may appear as both an Adverse Event (AE) and Serious Adverse Event (SAE). However, what is presented are distinct events. An event may be categorized as serious in 1 participant and as non serious in another participant, or 1 participant may have experienced both a serious and non serious event during the study. Safety population included all participants who used the study medication and provided a safety evaluation.