The purpose of this study is to compare the safety and efficacy profiles of Tazarotene Cream, 0.05% and Tazorac® (Tazarotene) Cream, 0.05% in order to demonstrate bioequivalence and to demonstrate the superiority of the 2 active creams over that of the Vehicle (placebo) in the treatment of plaque psoriasis.

This is a double-blind, randomized, parallel-group, vehicle-controlled, multicenter study of Tazarotene Cream, 0.05% in subjects with plaque psoriasis. Subjects will be randomly assigned in a 1:1:1 ratio to Test, Reference, or Vehicle.

Subjects will be admitted into the study after informed consent has been obtained and all inclusion/exclusion criteria have been met. At each visit, the same investigator (whenever possible) will grade the clinical signs of plaque psoriasis at the designated target lesion site using the Psoriasis Area Severity Index (PASI), an Investigator's Global Assessment (IGA) of disease severity will be performed (IGA scores range from 0 = none to 5 = very severe), and application site reactions (erythema, dryness, burning/stinging, erosion, edema, pain, and pruritus) will be assessed. In addition, the involved body surface area (BSA) will be determined at Visit 1 and Visit 4. Safety will be assessed by monitoring all adverse events (AEs) at each visit and a telephone contact at Day 7 (+ 4 days)

Inclusion Criteria:

1. Be willing and able to provide written informed consent for the study
2. Be male or female, at least 18 years of age
3. Have a definite clinical diagnosis of stable (at least 6 months) plaque psoriasis, involving at least 2% and no more than 20% of the body surface area (BSA) (not including the scalp and intertriginous areas)
4. Have a minimum plaque elevation at the target lesion site of at least moderate severity (grade ≥ 3 on the Psoriasis Area Severity Index [PASI]). The most severe lesion at baseline should be identified as the target lesion
5. Have an Investigator's Global Assessment (IGA) of disease severity of at least moderate (score ≥ 3) as an overall assessment of all lesions to be treated.
6. Be in general good health and free from any clinically significant disease other than psoriasis that might interfere with the study evaluations
7. Be willing and able to understand and comply with the requirements of the study, apply the study medication as instructed, return for the required treatment period visits, comply with therapy prohibitions, and be able to complete the study
8. Female subjects of childbearing potential (excluding women who are surgically sterilized or postmenopausal for at least 2 years) must have a negative urine pregnancy test having sensitivity down to at least 50 mIU/ml for hCG, begin treatment during a normal menstrual period and must be willing to use an acceptable method of contraception during the study. The following are considered acceptable methods of birth control for the purpose of this study: oral contraceptives, contraceptive patches, contraceptive implant, vaginal contraceptive, double barrier methods (e.g., condom and spermicide), contraceptive injection (Depo-Provera®), intrauterine device (IUD), hormonal IUD (Mirena®), and abstinence with a documented second acceptable method of birth control if the subject becomes sexually active. Subjects entering the study who are on hormonal contraceptives must have been on the method for at least 90 days prior to the study and continue the method for the duration of the study. Subjects who had used hormonal contraception and stopped must have stopped no less than 90 days prior to Visit 1/Day 1
9. Be willing to limit sun exposure overall, maintain a reasonably constant exposure, and avoid use of tanning booths or other UV light sources during their participation in the study

Exclusion Criteria:

1. A female subject who is pregnant, nursing, planning a pregnancy, or does not agree to use an acceptable form of birth control within the study participation period
2. Have a current diagnosis of unstable forms of psoriasis in the treatment area, including pustular, guttate, exfoliative or erythrodermic psoriasis
3. Have a history of psoriasis unresponsive to topical treatments
4. Have other inflammatory skin disease in the treatment area that may confound with the evaluation of plaque psoriasis (e.g., atopic dermatitis, contact dermatitis, eczema, tinea corporis)
5. Have pigmentation, extensive scarring, pigmented lesions, or sunburn in the treatment areas that could interfere with the rating of efficacy parameters
6. Have an unstable medical disorder, life-threatening disease, or current malignancy
7. Have current immunosuppression
8. Have received any treatment listed in Table 8 1 more recently than the indicated washout period prior to Visit 1/Day 1
9. Would continue to receive any treatment listed in Table 8 1 during the study