Cancer Prevention/Interception Agent Development

The number of cancer preventive/interceptive agents utilized clinically remains disappointingly few. After nearly four decades of research in the development of these agents, we need to take advantage of the progress that has been made in our understanding of early-stage cancer and premalignant lesions to maximize efforts to prevent or intercept cancer. It is crucial to identify the high-risk population and the appropriate target pathways and to use animal models that accurately represent early-stage human lesions and demonstrate at least a 50% reduction in tumor development. Determination of the agent's physiochemical properties, toxicities, solubility, and accumulation in the intended target organ needs to be verified. Tolerability is important, as these agents will be administered for an extended period to healthy individuals at higher risk for cancer. Reduction of side effects through the use of lower concentrations of agents in drug combinations, alternative delivery systems, and different dosing schedules should be considered. Collaboration with industry partners early in the development process to facilitate the movement of agents into clinical trials, including the necessary investigational new drug-enabling toxicology studies, manufacturing, and commercialization, is crucial. Moving forward, cancer prevention/interception will likely rely on combinations of vaccines with chemo/immunopreventive agents to reduce cancer mortality.