Comparative study of photodynamic therapy with 5%, 10% and 20% aminolevulinic acid in the treatment of generalized recalcitrant facial verruca plana: a randomized clinical trial

Abstract Background Generalised recalcitrant facial verruca plana responds poorly to current therapeutic options, including cryotherapy, topical drugs and carbon dioxide (CO 2 ) laser. Case reports and uncontrolled studies suggested that topical photodynamic therapy (PDT) is effective choice of treatment free from potential complications associated with invasive therapies. Aims To investigate the efficacy and safety of PDT with different concentrations of photosensitiser in the treatment of verruca plana. Materials & Methods The two sides of a subject's face were separately randomized to receive aminolevulinic acid (ALA) of 5%, 10% or 20% concentration. All patients were irradiated with 633‐nm red light for 339 J/cm 2 total dose. Complete response (CR) rate was assessed on Week 4, 8, and 16 respectively. Results The mean overall clearance rate was 74.1%, 68.8%, and 64.6% on Week 4, 8, and 12, respectively, in the 110 treated sides. The CR rate was lower in the 5%‐ALA group than in the 10%‐ALA group (14.3% vs . 33.3%, p < 0.05) and 20%‐ALA group (14.3% vs . 26.3%, p < 0.05) after 12 weeks. The mean severity of pain measured by visual analogue scale (VAS) scoring was 3.8 (range: 2 to 10, depending on the lesion location). The overall recurrence rate was 16.7% (4/24) on Week 12. Hyperpigmentation was observed in 61% (67/110) of all treated sides. On Week 4, 8, and 16, hyperpigmentation was more developed in the 20%‐ALA group than in the other two groups ( p < 0.05). Discussion In terms of complete clearance rate, the 5% ALA‐PDT group was significantly inferior to the 10% and 20% ALA‐PDT groups at each follow‐up. In contrast, the 20% ALA group showed a higher incidence rate of transient hyperpigmentation than the other two groups. Conclusions This randomised clinical trial suggests that PDT with ALA of 10% concentration offers better efficacy and safety than 5% or 20% concentration for generalised recalcitrant facial verruca plana.