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

Abstract

Objective: 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.

Design: Randomized, placebo-controlled, uneven parallel-group study.

Interventions: 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.

Main outcome measure: Clinical response based on lesion clearing by week 8.

Results: 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<.001, Cochran-Mantel-Haenszel general association test). The 95% confidence interval for the difference in response rates at week 8 was 46.9% to 71.0% and at week 12, 65.3% to 86.3%. The week 12 response rate includes 30% of patients who received a second treatment. Most patients experienced erythema and edema at the treated sites, which resolved or improved within 1 to 4 weeks after therapy, and stinging or burning during light treatment, which decreased or resolved by 24 hours after light treatment.

Conclusion: Findings indicate that topical ALA PDT is an effective and safe treatment for multiple actinic keratoses of the face and scalp.