Safety and efficacy of a fixed combination of halobetasol and tazarotene in the treatment of moderate-to-severe plaque psoriasis: Results of 2 phase 3 randomized controlled trials

Background: Topical corticosteroids are the mainstay of psoriasis treatment, with long-term safety considerations limiting their use. Combining them with tazarotene may optimize their efficacy and minimize safety and tolerability concerns. Objective: To investigate the safety and efficacy of halobetasol propionate 0.01% plus 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) were conducted. Subjects were randomized (2: 1) to HP/TAZ lotion or vehicle once daily for 8 weeks with a 4-week follow-up. The primary efficacy assessment end point was treatment success (at least a 2-grade improvement from baseline in Investigator's Global Assessment score and a score of clear or almost clear). Safety and treatment-emergent adverse events were evaluated throughout. Results: HP/TAZ lotion demonstrated statistically significant superiority over vehicle within as few as 2 weeks. By week 8, 35.8% (study 1) and 45.3% (study 2) of subjects were treatment successes compared with 7.0% and 12.5% of those treated with vehicle (P<.001). HP/TAZ lotion was also superior in reducing signs and symptoms of psoriasis and body surface area affected by psoriasis. The most frequently reported treatment-related adverse events were contact dermatitis (6.3%), application site pain (2.6%), and pruritus (2.2%). Limitations: Studies did not include subjects with more than 12% of their body surface area affected by psoriasis. Conclusions: HP/ TAZ lotion was associated with significant reductions in the severity of the clinical signs of psoriasis, with no safety concerns.