Efficacy and safety of tretinoin 0.05% cream to prevent hyperpigmentation during narrowband UV-B phototherapy in patients with facial vitiligo: a randomized clinical trial

Background: Narrowband UV-B (NBUVB) phototherapy is the mainstay of vitiligo treatment, but hyperpigmentation is one of the limitations. Meanwhile, topical tretinoin is effective against pigmentary disorders. Objective: To determine whether tretinoin 0.05% cream would prevent hyperpigmentation when patients with facial vitiligo underwent phototherapy. Methods: A randomized, controlled, split-face trial was conducted. Adult patients with stable, non-segmental facial vitiligo were enrolled. The left/right sides of the face were randomly allocated to receive either topical tretinoin 0.05% cream or moisturizer twice daily. The entire face was subjected to NBUVB phototherapy twice weekly for 12 weeks. The degree of hyperpigmentation was assessed as the delta L* (brightness) value of the darkest spot in each side of the face at baseline and every 4 weeks. The degree of repigmentation was assessed. Results: Twenty-five patients were enrolled; 21 completed the study. The delta L* value was significantly different between the two groups: −0.5% in the tretinoin group and −8.7% in the control group at 12 weeks (p =.002). Marked repigmentation was achieved in 15 patients of both groups. Conclusions: Tretinoin 0.05% cream prevented hyperpigmentation during NBUVB phototherapy in patients with facial vitiligo, and did not compromise the overall treatment response. Trial registration: ClinicalTrials.gov NCT03933774.