An agent consisting of chlorin e6, derived from chlorophyll, and L-aspartic acid with photosensitizing activity. After intratumoral activation by light emitting diodes, taporfin sodium forms an extended high energy conformational state that generates singlet oxygen, resulting in free radical-mediated cell death. or A drug used in photodynamic therapy. When absorbed by cancer cells and exposed to light, the drug becomes active and kills the cancer cells.