PPA-904

PPA-904 is a small molecule phenothiazine-based photosensitizer developed for use in photodynamic therapy (PDT), particularly as a topical treatment. Its mechanism of action involves the generation of reactive oxygen species upon activation by red light (around 660–665 nm), leading to local cytotoxic effects and immunomodulation. It has been investigated primarily for cutaneous leishmaniasis, chronic leg ulcers, diabetic foot ulcers, wounds and injuries, and actinic keratosis. In preclinical and clinical studies, topical application followed by irradiation resulted in antimicrobial activity (notably against MRSA and Pseudomonas aeruginosa) and promoted wound healing through immunomodulatory effects such as increased IL-12p70 production. The drug was initially developed by Photopharmica but development was discontinued after reaching phase 3 trials[1][2][3][4][5][7].

Other names

Phenothiazin-5-ium, 3,7-bis(dibutylamino)-, bromide