Topical calcitriol in the treatment of chronic plaque psoriasis: a double-blind study

A randomized, double-blind, left-right, vehicle-controlled study to assess the therapeutic efficacy and safety of twice daily application of 15 micrograms/g calcitriol ointment for a period of 6 weeks was performed in 32 patients suffering from bilateral, symmetrical, severe chronic plaque psoriasis. Twice daily 15 micrograms/g calcitriol ointment significantly improved erythema, induration, scaling and global severity of psoriatic plaques, and was much more effective than vehicle ointment. The difference in overall clinical efficacy between calcitriol and vehicle was statistically significant from week 1 onwards, and was maintained over the entire study. On completion of the study, clearance of psoriatic lesions was found in 47% of calcitriol-treated sides and in 13% of vehicle-treated sides. Skin histopathology of calcitriol-treated sides revealed a return to normal keratinization, with decreased inflammatory cell infiltration in the dermis and disappearance of the inflammatory infiltrate from the epidermis. Three patients had asymptomatic hypercalcaemia during the study. Mean serum levels of total calcium, albumin-adjusted total calcium, phosphorus, 25-hydroxyvitamin D and calcitriol did not show statistically significant changes in the baseline/end-point comparisons.