13568 Efficacy of ALA-PDT in the treatment of actinic keratoses on the upper extremities: A post hoc analysis of a phase 3, randomized, vehicle-controlled trial

Abstract

Aminolevulinic acid (ALA) 20% solution photodynamic therapy (PDT) is indicated for targeted treatment of actinic keratosis (AK) on the face, scalp, and upper extremities. In a phase 3 study of 135 subjects (NCT02137785), ALA 20% solution–PDT at baseline and week 8 using lesion-targeted treatment and a 3-hour occluded incubation was superior to vehicle (VEH)–PDT for AK clearance of the upper extremities. Results of that study assessed response of the entire field to treatment, including new AKs present at follow-up, in calculations of clearance rates. This ancillary analysis assesses treated AKs only, since treatment was delivered as targeted treatment rather than field-directed. Analyses include mean AK clearance rate compared with baseline, cumulative disease area clearance and subgroup analysis of complete clearance rate by lesion size. The mean AK clearance rate for ALA-treated lesions of all sizes was 81% at 12 weeks (after up to two treatments), compared with 45% for lesions receiving VEH (P 36 mm2 in size, respectively. Mean cumulative disease area at baseline was 149 mm2 and 154 mm2 for ALA and VEH-treated AKs respectively; 82% of the cumulative disease area was cleared at week 12 after ALA-PDT compared with 43% after VEH-PDT. ALA-PDT resulted in high clearance rates of treated AKs, including good response of large AKs and high mean cumulative area clearance rates.