Update of the situation of clinical photodynamic therapy in Europe in the 2003–2018 period

Photodynamic therapy has become of interest in many European countries. Since, most of national authorities and all medical journals require the registration of the clinical study on the database ClinicalTrials. gov in order to be published, information regarding clinical studies are now available. This article aims to synthetize data gathered thanks to this database. The keywords used for this analysis was: (i) status: “All studies “(recruiting, completed, terminated, we did not take into account unknown status), (ii) condition or disease: “Photodynamic Therapy”, (iii) country: name of each European country. Since 2003, 76 clinical trials were registered in Europe. Most clinical studies are performed in Germany (22), France (20) and UK (19). These 3 countries represent 80% of all studies performed in Europe. However 21 European countries have one or more studies on PDT. Clinical studies were mainly performed on skin. Actinic Keratosis treatment (20 studies) represents more than 45% of all studies. 21% were focused on eye, mainly on Age Macular Degeneration (AMD) (8 studies). In 2018, ten (10) clinical trials are in the recruitment phase. On November, 10, 2017, Padeliporfin (STEBA Biotech S.A, Luxembourg) obtained the marketing authorization throughout the European Union. Despite the critical importance of trial registration, compliance with requirements from governmental regulators which mandate the prospective registration of clinical trials has been imperfect. Besides, a large proportion of registry entries are never updated to reflect study completion. However, this review clearly demonstrated that PDT is progressively used in most European countries.