Safety and Efficacy of IDP-118 Lotion to Ultravate® in the Treatment of Plaque Psoriasis

Key Inclusion Criteria: * Male or female, of any race, at least 18 years of age (inclusive). * Freely provides both verbal and written informed consent. * Has an area of plaque psoriasis appropriate for topical treatment that covers a BSA (Body Surface Area) of at least 3%, but no more than 12%. The face, scalp, palms, soles, axillae, and intertriginous areas are to be excluded in this calculation. * Is willing and able to avoid prolonged exposure of the treatment area to ultraviolet radiation (natural and artificial) for the duration of the study. * Has a clinical diagnosis of psoriasis at the Baseline visit with an IGA (Investigators Global Assessment) score of 3 or 4. (The face, scalp, palms, soles, axillae, and intertriginous areas are to be excluded in this assessment, if psoriasis is present.) * If female and of childbearing potential, must have a negative urine and serum pregnancy test at the Screening visit and negative urine pregnancy at Baseline visit prior to randomization. * Subject is willing to comply with study instructions and return to the clinic for required visits. Key Exclusion Criteria: * Has spontaneously improving or rapidly deteriorating plaque psoriasis or pustular psoriasis, as determined by the investigator. * Presents with psoriasis that was treated with prescription medication and failed to respond to treatment, even partially or temporarily, as determined by the investigator. * Presents with any concurrent skin condition that could interfere with the evaluation of the treatment areas, as determined by the investigator. * Is pregnant, nursing an infant, or planning a pregnancy during the study period. * Has received treatment with any investigational drug or device within 60 days or 5 drug half-lives (whichever is longer) prior to the Baseline visit, or is concurrently participating in another clinical study with an investigational drug or device.