Effectiveness of clobetasol propionate spray 0.05% added to other stable treatments: add-on therapy in the COBRA trial.

Controlled clinical trials provide important information about medications. However, although controlled clinical trials typically assess the use of a medication by itself or in a single combination, combinations and adjunctive use of multiple medications frequently are used in the care of patients with psoriasis. The Clobex Spray Community-Based Research Assessment (COBRA) trial, a large, 4-week, open-label, observational, community-based trial, assessed the use of twice-daily clobetasol propionate spray 0.05% as an add-on therapy to an existing therapeutic regimen in subjects (n = 731) with moderate to severe plaque psoriasis affecting 3% to 20% body surface area (BSA). The key outcome measures were the change in target plaque severity (TPS) and investigators' global assessment of improvement (GAI) at week 4. Tolerability, quality of life (QOL), and subject satisfaction also were assessed. After 4 weeks of treatment, 80.0% of subjects in the add-on therapy group were clear or almost clear, according to the TPS scale, or had an improvement in severity from baseline by 2 grades (P < .001); 62.0% of subjects were completely cleared or almost completely cleared at week 4 according to the GAI scale (P < .001). Tolerability ratings of severe for erythema, peeling/ scaling, dryness, and stinging/burning occurred in less than 1.0% of subjects at week 4, and a rating of moderate occurred in only 1.6% to 4.1% of subjects. In addition, 94.0% of subjects in the add-on therapy group were reported as being very satisfied or somewhat satisfied with their therapy at week 4. Clobetasol propionate spray 0.05% was highly effective and well-tolerated as part of a wide range of therapeutic strategies.