Trends in Drug Targeting for Cancer Treatment

Various drug delivery and targeting systems and approaches are currently utilized for cancer chemotherapy. Many drugs being developed through biotechnology are also in various stages of clinical trials. The most common approaches with drug delivery and targeting systems have been those using stealth liposomes or microspheres. Recent efforts have been made to use stealth nanoparticles for cancer drug delivery. In the next few years, it is expected that several liposomal products will be on the market. Another approach that has been utilized for some time has been the use of antibody-directed drugs or toxins. Several immunotoxins are currently in phase III trials, and efforts are being made to potentiate their activity with different potentiators. In an effort to understand the intricacies of tumor morphology and the limitations of drug targeting, various mathematical models have been proposed that help in designing appropriate delivery systems for successful tumor targeting. This review considers a number of drug targeting systems, especially microparticulate and colloidal systems, for cancer therapy.