Pilot, multicenter, double-blind, randomized placebo-controlled bilateral comparative study of a combination of calcipotriene and nicotinamide for the treatment of psoriasis.

Background: Calcipotriene has limited efficacy in treating psoriasis. By inhibiting proinflammatory cytokines such as interleukin-12, interleukin-23, and tumor necrosis factor-alfa, nicotinamide may enhance the efficacy of calcipotriene therapy when used in combination.

Objective: We sought to determine if the combination of nicotinamide with calcipotriene is more effective than either component alone.

Methods: In this randomized, double-blinded, multicenter 7-arm bilateral comparison-controlled trial, patients were randomized to two of 7 treatments--placebo, calcipotriene 0.005% alone, nicotinamide 1.4% alone, calcipotriene plus nicotinamide 0.05%, calcipotriene plus nicotinamide 0.1%, calcipotriene plus nicotinamide 0.7%, or calcipotriene plus nicotinamide 1.4%--each administered to lesions on one side of the body or to one of two lesions at least 5 cm apart, for 12 weeks. Efficacy was measured using a clear to almost clear outcome.

Results: In all, 50.0% of patients in the calcipotriene and nicotinamide 1.4% combination group achieved a clear to almost clear outcome at week 12, compared with only 18.8% of patients treated with placebo (P = .002), 25% of patients treated with nicotinamide 1.4% alone (P = .02), and 31.5% of patients treated with calcipotriene alone (P = .096). A dose-response trend existed for increasing concentrations of nicotinamide, but it was not significant.

Limitations: The relatively small patient numbers, relatively high placebo effect, and maximum in-life portion of only 12 weeks of dosing are weaknesses of the study.

Conclusion: This study provides evidence that using the combination nicotinamide and calcipotriene may provide additional benefit in the topical treatment for patients with psoriasis and may be an adequate steroid-sparing substitute treatment.