A Randomized, Double-blind, Placebo-controlled Study to Evaluate the Safety and Efficacy of Ammonium Lactate Lotion 12% and Halobetasol Propionate Ointment 0.05% in the Treatment and Maintenance of Psoriasis.

Consensus recommends a gradual reduction in the frequency or steroid potency of topical corticosteroids following clinical improvement in the treatment of psoriasis, although no established guidelines have been developed. The authors sought to evaluate a combination regimen in the treatment and maintenance of psoriasis. Patients with mild-to-moderate psoriasis were enrolled (n=55) in a randomized, double-blind, placebo-controlled study using ammonium lactate lotion and halobetasol ointment. Those with initial improvement of target plaques after two weeks of combination treatment twice daily were randomized to a maintenance phase (n=41). Patients applied ammonium lactate lotion twice daily everyday and either placebo ointment (n=20) or steroid ointment (n=21) twice daily on weekends only. Forty-one of 55 patients (74.6%) were rated as "clear" (0) or "almost clear" (1) after two weeks of combination treatment. In the maintenance phase, the probability of physician global assessment worsening at six weeks in the steroid group was only 10 percent while in the placebo group the probability rose to 75 percent (p<0.0001). The probability of physician global assessment worsening climbed to 100 percent by 14 weeks in the placebo group while only increasing to 29 percent in the steroid group (p<0.0001). Twelve patients at study termination still had not worsened. Worsening of the physician global assessment index was more likely (HR 7.8 [2.84, 21.43]) in the placebo group than in the steroid group (p<0.0001). No cutaneous side effects, such as steroid atrophy or irritation, were noted. Combination treatment effectively cleared plaque psoriasis initially, and ammonium lactate twice daily everyday with weekend-only applications of halobetasol ointment effectively sustained the initial improvement for a significantly longer period of time when compared with placebo without demonstrating any significant side effects, such as steroid atrophy.