5-ALA loaded self-adhesive patch-PDT is effective and safe in the treatment of actinic keratoses on hands and arms.

Photodynamic therapy (PDT) with 5-aminolevulinic acid hydrochloride (ALA) is an established method for the management of AK. PD P 506 A (brand name Alacare®) is an approved medicinal product for the treatment of AK located on scalp and face. It is a self-adhesive, light-proof patch loaded with 5-ALA HCl and was developed for easy handling. AK located on arms, hands or trunk do not respond as well to ALA-PDT as AK lesions on the head do. It has been reported that occlusion during ALA incubation can improve clinical outcome after ALA-PDT for AK on hands and arms. We present the results of a first explorative pilot study involving 20 participants with a total of 145 treated (122 evaluable) AK lesions. The trial investigated the conduct of two ALA-PDTs within 1-2 weeks and involved all severity grades of AK. The model-based percentage of complete clearance on lesion-basis was estimated being 78.0% (95%-CI: [64.6%, 87.3%]), and the by-participant calculation (patient-based clearance) led to similar results (78.7% with a 95%-CI of [67.0%, 90.3%]). The treatment was well tolerated. Local reactions during ALA patch incubation were rare whereas nearly all patients showed the expected reactions during or after the illumination, primarily erythema and pain. The study results indicate that two PD P 506 A-PDT sessions 1-2 weeks apart are an efficacious treatment for AK on hands and arms. Especially mild but also moderate lesions responded very well to PDT treatment involving ALA incubation under occlusion.

Photodynamic therapy with a 5-ALA patch does not increase the risk of conversion of actinic keratoses into squamous cell carcinoma: Results of a multicentre non-interventional study.

BACKGROUND: It is important to collect data about the risk of transformation of an actinic keratosis (AK) lesion into squamous cell carcinoma (SCC) after a single photodynamic therapy (PDT) with 5-ALA patch for a longer follow-up period under daily routine. QUESTIONS ADDRESSED: The purpose of this non-interventional study (NIS) was to collect data on the frequency of occurrence of SCCs in the treated area during an interval of 2 years after a single 5-ALA patch-PDT. EXPERIMENTAL DESIGN: This prospective observational case-only study included patients with mild AK lesions on the head and face treated with 5-ALA patch-PDT according to the Summary of Product Characteristics (SPC). RESULTS: In 370 patients, the risk of transformation of their treated AK lesion into SCC was 0.073% with its exact 95% confidence interval using the Poisson distribution of [0.009%, 0.262%]. The rate of complete clinical clearance on lesion basis after 3 months was 84.3%. CONCLUSION: The efficacy and the safety results show no observation of an increased risk for conversion of an AK into a SCC 2 years after a single 5-ALA patch-PDT. Additionally, the high clinical complete remission rate under routine conditions is comparable to the rates observed in the approval trials.

Fluorescence characteristics and pharmacokinetic properties of a novel self-adhesive 5-ALA patch for photodynamic therapy of actinic keratoses.

Actinic keratosis (AK) can be treated by photodynamic therapy (PDT), which is becoming a well-established tool in dermatology. Normally a precursor of the photosensitiser is applied topically and converted into protoporphyrin IX (PPIX) in the cells. By activating PPIX with light, the dysplastic cells will be destroyed. We report the results of two clinical studies investigating the properties of a novel self-adhesive 5-ALA-patch (PD P 506 A) intended for PDT of mild to moderate AK on the face and head. The studies investigated the influence of patch application duration on PPIX-specific fluorescence and the pharmacokinetic properties of the 5-ALA patch. The PPIX fluorescence in AK lesions and normal skin after patch application (intraindividual comparison; application for 2, 3, 4, 5 h) was investigated in 13 patients using DYADERM Professional (Biocam). In the subsequent pharmacokinetic study 12 patients were treated with 8 patches each (4 h application). 5-ALA and PPIX were analysed in plasma (over 24 h) and urine (over 12 h). PPIX-specific fluorescence measured immediately after patch removal increased with increasing application duration to a maximum at 4-h application. The fluorescence in AK lesions was more intense than in normal skin. A small increase of 5-ALA plasma concentrations was observed in 10 of 12 patients after applying 8 patches for 4 h, which rapidly declined to normal values after patch removal. The maximum increase was 3.7-fold of the pre-dose 5-ALA plasma concentration. No PPIX-concentrations above the lower limit of quantification were observed. PPIX-specific fluorescence in AK lesions can be steered by application duration of this novel 5-ALA patch. Application is safe and well tolerable. The observed small rise in 5-ALA plasma concentrations is regarded clinically irrelevant. Clinical efficacy of the patch in PDT will be investigated in further clinical trials.