Study to Evaluate the Safety and Efficacy of BF-200 ALA (Ameluz®) and BF-RhodoLED® in the Treatment of Superficial Basal Cell Carcinoma (sBCC) With Photodynamic Therapy (PDT).

The study will be conducted as randomized, double blind and vehicle-controlled ( 4:1 ratio of verum (BF-200 ALA; Ameluz®) to vehicle (placebo)) clinical trial at 15 sites in the United States of America (US). Each site should randomize between 10 and 20 subjects.

Each subject will complete a clinical observation period that will last for up to 7 months (up to 4 weeks screening and pre-randomization period, and up to 6 months clinical observation period) followed by a 5-year follow-up (FU) period after the completion of the first PDT cycle.

The treatment of superficial BCC lesion(s) comprises of up to two PDT cycles each with two PDT sessions one to two weeks apart of each other. 12 weeks after the first PDT of the first cycle lesion(s) will be assessed clinically and only subjects with remaining BCC lesion(s) will be retreated in the second PDT cycle starting the same day. For clinically completely cleared subjects the clinical observation period of the study will end and these subjects will enter the FU part of the study.

For each subject a Main Target Lesion will be defined that will be excised either 12 weeks after the first PDT of the first cycle, if clinically cleared, or at the end of the clinical observation period in order to histologically confirm the clinical assessment. Additional Target Lesions will be assessed clinically, only. Randomization will be stratified by the number of lesions (1 vs ≥2 Lesion(s)).

Definitions of complete responders comprise of:

1. Complete response of the Main Target Lesion which is assessed 12 weeks after the start of the last PDT cycle that included treatment of the Main Target Lesion and is defined as a Main Target Lesion that is completely clinically and histologically cleared. 2. In general, clinically complete responders are categorized 12 weeks after the start of the last PDT cycle according to clinical assessment only and are defined as subjects with all lesions (Main plus Additional Target Lesions) clinically cleared.

Verum and vehicle are indistinguishable. However, treatment is accompanied with typical adverse events (AEs). In order to guarantee the blind status of the investigator assessing efficacy after each PDT cycle, a second investigator or delegated person will perform drug application and light treatment as well as all safety evaluations at visits where PDT is applied and during the phone call 1 week after each PDT cycle, respectively. Both investigators (delegated person(s)) are not entitled to exchange information about the study outcome and side effects.