Optimization of photodynamic therapy with a novel self-adhesive 5-aminolaevulinic acid patch: results of two randomized controlled phase III studies


  • Conflicts of interest
    A.H. and R.-M.S. receive speaker honoraria from photonamic GmbH & Co. KG. C.O., A.C.E.M. and M.S. are employees of photonamic. M.B. is an employee of the company that was put in charge of data management and statistical issues. R.-M.S. was involved in inventing the product. The other authors have no conflict of interest to declare.

Axel Hauschild.
E-mail: ahauschild@dermatology.uni-kiel.de


Background  Photodynamic therapy (PDT) is increasingly used for treatment of actinic keratoses (AKs) but is a cumbersome procedure. A thin self-adhesive patch (PD P 506 A) containing 5-aminolaevulinic acid (5-ALA) was developed to facilitate PDT.

Objectives  To investigate efficacy and safety of the patch in comparison with placebo–PDT (superiority design, observer-blinded; study AK 03) and standard therapy, cryosurgery (noninferiority design, open; study AK 04).

Methods  Two separate confirmatory randomized parallel-group phase III studies were set up. In total, 449 patients with up to eight mild to moderate AK study lesions located on the head were treated in 29 German study centres (study AK 03: 103 patients; study AK 04: 346 patients).

Results  Twelve weeks after treatment, 5-ALA patch–PDT proved to be superior to placebo–PDT (P < 0·001) and cryosurgery (= 0·007). Efficacy rates on a lesion basis were 82% (AK 03) and 89% (AK 04) for PDT, 77% for cryosurgery and 19% (AK 03) and 29% (AK 04) for placebo–PDT. Local reactions at the treatment site occurred in almost all patients treated with 5-ALA patch–PDT or cryosurgery. Headache was the only side-effect not related to the treatment site which occurred in more than one patient.

Conclusions  PD P 506 A is an innovative, easy-to-handle 5-ALA patch for PDT of mild to moderate AK lesions. Compared with current PDT procedures, pretreatment (e.g. curettage) is not needed and handling is considerably facilitated. A single PDT treatment results in efficacy rates being statistically significantly superior to placebo and cryosurgery.