In NEJM this week, Bruce Chabner says the "striking" results of recent Phase I trials for targeted cancer drugs have started a discussion about shortening the process required to get approval from regulators. Normally, it takes a cancer drug about seven years to go from human trials to FDA approval, but the news of success in Phase I trials reaches physicians early and creates demand for access to the drug, Chabner says. New understanding of the hand genetics plays in cancer development has only "sharpened" the discussion by enabling rapid development of targeted therapies, he adds, and because patient subgroups with high response rates to certain drugs can now be defined, Phase I trials are becoming even more successful. The mechanism of "accelerated approval," which the FDA introduced in 1992 to quickly approve drugs meant for life-threatening diseases with no effective treatment, could be used in the case of targeted cancer drugs that show promise in Phase I trials, Chabner says. "Early approval would allow rapid general access to treatment, while further evaluation focused on defining optimal doses, schedules, and drug combinations; long-term benefits; toxic effects; and resistance mechanisms," he adds.
Published online in advance in NEJM this week, a group of clinicians ask whether the link between vitamin D and cancer prevention is ready for "prime time." Given the potential of vitamin D to prevent cancer, many were surprised that an increase intake of the vitamin didn't figure prominently in the new Dietary Reference Intakes established by the Institute of Medicine. Although IOM concluded that vitamin D plays an important role in bone health, it was determined that the evidence linking vitamin D to cancer and other diseases was "inconsistent and inconclusive as to causality," the authors write. The premise is biologically plausible, they add, but more evidence is needed.