Photodynamic therapy with aminolevulinic acid topical solution and visible blue light in the treatment of multiple actinic keratoses of the face and scalp investigator-blinded, phase 3, multicenter trials

To determine the safety and efficacy of photodynamic therapy (PDT) using 20% wt/vol aminolevulinic acid hydrochloride (hereinafter "ALA") and visible blue light for the treatment of multiple actinic keratoses of the face and scalp. Randomized, placebo-controlled, uneven parallel-group study. Patients (N = 243) were randomized to receive vehicle or ALA followed within 14 to 18 hours by PDT. Follow-up visits occurred 24 hours and 1, 4, 8, and 12 weeks following PDT. Target lesions remaining at week 8 were re-treated. Clinical response based on lesion clearing by week 8. Most patients in both groups had 4 to 7 lesions. Complete response rates for patients with 75% or more of the treated lesions clearing at weeks 8 and 12 were 77% (128/166) and 89% (133/149), respectively, for the drug group and 18% (10/55) and 13% (7/52), respectively, for the vehicle group (P