Safety and efficacy of a fixed combination halobetasol and tazarotene lotion in the treatment of moderate-to-severe plaque psoriasis: A pooled analysis of two phase 3 studies

Background: Topical corticosteroids (TCS) are the mainstay of psoriasis treatment. Safety concerns may limit use. Combination with tazarotene may optimize efficacy and minimize safety and tolerability concerns. Objective: Investigate safety and efficacy of halobetasol propionate 0.01%/tazarotene 0.045% (HP/TAZ) lotion in moderate-to-severe plaque psoriasis. Methods: Two multicenter, randomized, double-blind, vehicle-controlled phase 3 studies (N=418). Subjects randomized (2:1) to HP/TAZ lotion or vehicle once-daily for 8 weeks, 4-week follow-up. Primary efficacy assessment: Treatment success (at least a 2-grade improvement from baseline in IGA score and 'clear' or 'almost clear'). Safety and treatment emergent AEs evaluated throughout. Results: HP/TAZ lotion demonstrated statistically significant superiority over vehicle as early as week 2 (P=0.002). By week 8, 40.6% of subjects were treatment successes compared with 9.9% on vehicle (P<0.001). A third of subjects remained treatment successes post-treatment. HP/TAZ lotion was also superior in reducing psoriasis signs and symptoms, and Body Surface Area (BSA) involvement. Most frequently reported treatment related AEs were contact dermatitis (6.3%), application site pain (2.6%), and pruritus (2.2%). Limitations: No data were collected beyond the 4-week follow-up. Conclusions: HP/TAZ lotion provides synergistic efficacy that is both rapid and sustained, with good tolerability and safety over 8 weeks use.