Used primarily in photodynamic therapy, this compound is effective in treating abnormal blood vessel formation in the eye, particularly in conditions like wet age-related macular degeneration. When activated by light of a specific wavelength, it selectively damages overactive or malformed blood vessels in the retina, helping to slow vision loss. It is also being explored for use in certain cancers, where it can target and destroy rapidly dividing cells when exposed to light. Its ability to localize in rapidly growing tissues makes it valuable in targeted therapies with minimal impact on surrounding healthy tissue.