A clinical study to determine the efficacy and safety of 1% methotrexate/Azone® (MAZ) gel applied topically once daily in patients with psoriasis vulgaris

The efficacy and safety of an Azone-enhanced topical gel formulation of 1% methotrexate (MAZ), administered once daily for 8 weeks, was compared with that of placebo vehicle for the treatment of severe plaque psoriasis. Fifty-three patients were involved in this double-blind, paired-comparison study. Changes in disease signs and symptoms indicated that both agents have antipsoriatic activity; however, lesions treated with MAZ exhibited significantly greater improvement. At the end of treatment, 27% of MAZ-treated lesions demonstrated marked improvement, whereas none of the placebo-treated lesions exhibited this degree of change. MAZ was most effective in reducing lesional scaling and thickness (P < 0.05 vs. placebo). Thirty-seven patients experienced adverse events. The majority were local in nature and mild to moderate In degree. No clinically significant changes in hematologic or clinical laboratory parameters were observed, and concentrations of methotrexate were demonstrable in only two of 296 plasma samples. The findings suggest that the MAZ formulation provides percutaneous absorption of methotrexate in amounts sufficient for a beneficial effect in psoriasis, but insufficient to exert systemic toxicities.