Safety and Efficacy Study for the Field-directed Treatment of Actinic Keratosis (AK) With Photodynamic Therapy (PDT)

All efficacy variables were evaluated for the FAS. The primary efficacy variable was also analyzed for the PP population. All subgroup analyses were carried out for the FAS. Data for size and grade of AK lesions were analyzed using the last observation carried forward (LOCF) approach, affecting the response rates evaluation. Due to the small amount of missing data in the study, which did not have any relevant impact on primary results, sensitivity analyses for missing data were not performed. The primary efficacy variable was the overall patient complete response 12 weeks after the last PDT. An overall complete responder was defined as a patient in whom all treated actinic keratosis (AK) lesions were cleared (Olsen score of 0) after the last PDT, i.e. after PDT 1 or after PDT 2 if re-treatment was performed.

All efficacy variables were evaluated for the FAS. The primary efficacy variable was also analyzed for the PP population. All subgroup analyses were carried out for the FAS. Data for size and grade of AK lesions were analyzed using the last observation carried forward (LOCF) approach, affecting the response rates evaluation. Due to the small amount of missing data in the study, which did not have any relevant impact on primary results, sensitivity analyses for missing data were not performed. The primary efficacy variable was the overall patient complete response 12 weeks after the last PDT. An overall complete responder was defined as a patient in whom all treated AK lesions were cleared (Olsen score of 0) after the last PDT, i.e. after PDT 1 or after PDT 2 if re-treatment was performed.

For the secondary confirmatory analysis, several superiority hypotheses were tested within a pre-defined hierarchic multiple testing procedure as described in the Statistical Analysis Protocoll (SAP). The key secondary efficacy variables were tested strictly in a pre-defined order to ensure the family-wise error rate (FWER) and the testing procedure had to be stopped once the first non-significant test was obtained. The results of the confirmatory analysis are presented in the order pre-defined by the confirmatory testing procedure. Assessments of the patient histopathological confirmed response (HCR) rates were based on the results from the biopsy taken 12 weeks after the last PDT from a representative AK lesion selected at screening. If the biopsy result for a patient revealed a residual AK, the patient was considered "not cleared" for the analysis irrespectively of the investigator's clinical assessment.

The second key secondary efficacy variable in the hierarchic test procedure was the patient complete response (complete clearance of all treated AK lesions) assessed at 12 weeks after PDT 1.

The third key secondary efficacy variable in the hierarchic test procedure was the lesion complete response (completely cleared individual AK lesions) assessed at 12 weeks after last PDT.

The fourth key secondary efficacy variable in the hierarchic test procedure was the patient partial response (defined as complete clearance of at least 75% of treated AK lesions) assessed at 12 weeks after last PDT.

The fifth key secondary efficacy variable in the hierarchic test procedure was the change from baseline in the total lesion area per patient assessed at 12 weeks after last PDT.

Study personnel assessed and recorded the skin quality of the treated field(s) at baseline and at the end-of-study visit including skin surface, hyperpigmentation, hypopigmentation, mottled or irregular pigmentation, degree of scarring and atrophy. Upon visual examination of the treated field(s), the investigator coded the intensity of each skin parameter on a scale of 0 to 3, where 0 = none, 1 = mild, 2 = moderate, and 3 = severe. The cosmetic outcome evaluations were based on the sum score of the skin quality assessment (sum of all ratings for each skin parameter) at the end-of-study visit (Visit 4 or Visit 6, if retreated). The outcome was calculated using a 5-point scale ranging from "very good" (0) to "impaired" (4) based on the change of the skin quality assessments compared to baseline (0 = 2 points improvement; 1 = 1 point improvement; 2 = no change; 3 = 1 point worsened; 4 = at least 2 points worsened).

Study personnel assessed and recorded the skin quality of the treated field(s) at baseline and at the end-of-study visit including skin surface, hyperpigmentation, hypopigmentation, mottled or irregular pigmentation, degree of scarring and atrophy. Upon visual examination of the treated field(s), the investigator coded the intensity of each skin parameter on a scale of 0 to 3, where 0 = none, 1 = mild, 2 = moderate, and 3 = severe. The cosmetic outcome evaluations were based on the sum score of the skin quality assessment (sum of all ratings for each skin parameter) at the end-of-study visit (Visit 4 or Visit 6, if retreated). The outcome was calculated using a 5-point scale ranging from "very good" (0) to "impaired" (4) based on the change of the skin quality assessments compared to baseline (0 = 2 points improvement; 1 = 1 point improvement; 2 = no change; 3 = 1 point worsened; 4 = at least 2 points worsened).