The study looked specifically at outcomes of phase II trials. Data from phase II trials are used to determine whether a drug is promising enough to proceed to phase III trials, which ultimately determine whether the drug is approved by the U.S. Food and Drug Administration. The finding that phase II results can be influenced by patient travel distance raises the possibility of biased conclusions about which drugs should advance to phase III evaluation.
The study, conducted by Elizabeth B. Lamont, M.D., of the Massachusetts General Hospital Cancer Center in Boston, and her colleagues at the University of Chicago, involved 110 patients with head and neck cancer who were enrolled in one of four phase II clinical trials at the University of Chicago Medical Center. The authors looked at the association between overall survival and progression-free survival and the distance from the patient's home to the treatment center.
Patients who traveled 15 or more miles for their care had one-third the risk of death of those living closer, even after adjusting for standard disease and demographic factors. Moreover, for every 10 miles that a patient traveled for care, the risk of death decreased by 3.2%. A similar pattern was seen with progression-free survival.
The authors explain that patients who are able to obtain information on treatment options and have the resources to allow them to pursue those options may have better outcomes than patients who end up at the nearest place for care, even if their diseases and treatments are the same. The authors note that more work is needed to understand what individual and social factors travel distance is mediating.
In an accompanying editorial, Stephen L. George, Ph.D., of Duke University Medical Center in Durham, N.C., examines the new findings in the context of the FDA's relatively recent accelerated approval process, which allows drugs to be approved based on results of phase II trials. He advises caution when interpreting the results of phase II trials.
"Randomized trials comparing a new regimen against a control or placebo offer the best protection against the risks of erroneous conclusions inherent in phase II trials, especially for regulatory decisions," he concludes. "Accelerated approval may provide earlier access to potentially beneficial agents, but the evidence required for granting it should not come solely from phase II trials."
Editorial: Becky Levine, Duke University Medical Center, 919-684-4148, firstname.lastname@example.org.
Lamont EB, Hayreh D, Pickett KE, Dignam JJ, List MA, Stenson KM, et al. Is patient travel distance associated with survival on phase II clinical trials in oncology? J Natl Cancer Inst 2003;95:1370-75.
Editorial: George SL. Selection bias, phase II trials, and the FDA accelerated approval process. J Natl Cancer Inst 2003;95:1351-2.
Note: The Journal of the National Cancer Institute is published by Oxford University Press and is not affiliated with the National Cancer Institute. Attribution to the Journal of the National Cancer Institute is requested in all news coverage.