Oncologist Calls for Shorter Time to Approval of High-Value Targeted Cancer Drugs
New understanding of the mechanism of cancer as genetic and molecular cancer–causing lesions has enabled the development of targeted therapies that are producing excellent results in early clinical trials. This new understanding of the mechanism of cancer and the resultant development of superior therapies should shorten the time to drug approval by the US Food and Drug Administration (FDA), said Bruce A. Chabner, MD, Professor of Medicine, Harvard Medical School, and Director of Clinical Research, Massachusetts General Hospital Cancer Center, Boston, in a recent perspective in the New England Journal of Medicine (2011;364:1087-1090).
Recent phase 1 clinical trials of many targeted cancer drugs have produced excellent results and merit a change in the FDA requirement for long and costly randomized phase 3 trials. “When striking clinical results have been demonstrated in a sizable, readily identifiable patient population in phase 1, the journey to drug approval should not be prolonged,” Dr Chabner stated.
He cited the recent results of 2 new phase 1 trials (of patients who have not responded to standard therapies) with 2 agents—PLX4032, which produced an 81% response rate in 38 patients with melanoma with BRAF mutation, and crizotinib, with a 57% response rate in 82 patients with non–small-cell lung cancer EML4-ALK fusion. In both cases, the disease control rate for ≥8 weeks exceeded 90%, with little toxicity. Such results, he argues, require reconsideration of the prolonged and expensive process, especially for conditions with limited effective therapies. The value of these highly targeted therapies warrants an accelerated process.