Richard D. Swerdlow, PhD

Fenretinide (N-4-hydroxyphenyl-retinamide, or 4-HPR) is a semisynthetic retinoid that was initially developed as a low-dose chemopreventative agent.[1-3] Unlike other naturally occurring retinoids such as all-trans, 13-cis, and 9-cis retinoic acids, fenretinide does not induce systemic catabolism that interferes with the maintenance of effective plasma levels during long-term use. This characteristic, combined with the agent’s low toxicity and its ability to block aspects of carcinogenesis, provided the rationale for the development of fenretinide in lower doses as a chemoprevention agent for breast, prostate, and bladder cancer.