Is the efficacy of psoralen plus ultraviolet A therapy for vitiligo enhanced by concurrent topical calcipotriol? A placebo-controlled double-blind study

Background Encouraging results of previous uncontrolled trials suggest that calcipotriol may potentiate the efficacy of psoralen plus ultraviolet (UV) A (PUVA) therapy in patients with vitiligo. Objectives We performed a placebo‐controlled double‐blind study to investigate whether the effectiveness of PUVA treatment could be enhanced by combination with topical calcipotriol in the treatment of vitiligo. Methods Thirty‐five patients with generalized vitiligo enrolled in the study. Symmetrical lesions of similar dimensions and with no spontaneous repigmentation on arms, legs or trunk were selected as reference lesions. In this randomized left‐right comparison study, calcipotriol 0·05 mg g−1 cream or placebo was applied to the reference lesions 1 h before PUVA treatment (oral 8‐methoxypsoralen and conventional UVA units) twice weekly. Patients were examined at weekly intervals. The mean number of sessions and the cumulative UVA dosage for initial and complete repigmentation were calculated. Results Twenty‐seven patients (nine women, 18 men; mean ± SEM age 29·8 ± 13·5 years) were evaluated. The mean ± SEM cumulative UVA dose and number of UVA exposures for initial repigmentation were 52·52 ± 6·10 J cm−2 and 9·33 ± 0·65 on the calcipotriol side, and 78·20 ± 7·88 J cm−2 and 12·00 ± 0·81 on the placebo side, respectively (P < 0·001). For complete repigmentation, respective values were 232·79 ± 14·97 J cm−2 and 27·40 ± 1·47 on the calcipotriol side and 259·93 ± 13·71 J cm−2and 30·07 ± 1·34 on the placebo side (P = 0·001). Treatment with calcipotriol and PUVA resulted in significantly higher percentages of repigmentation for both initial (81%) and complete pigmentation (63%), compared with placebo and PUVA (7% and 15%, respectively). Conclusions Our results have shown that concurrent topical calcipotriol potentiates the efficacy of PUVA in the treatment of vitiligo, and that this combination achieves earlier pigmentation with a lower total UVA dosage.