Many Cancer Patients Are Ineligible for Trials
Many factors including age, the forms and staging of a cancer, a diagnosis of HIV and several blood chemistry values must all fall within predefined limits for a subject to be accepted for a clinical trial, reports Aimee Swartz in the Washington Post.
Clinical trials are concerned with meeting the Food and Drug Administration’s (FDA’s) definition of a new drug as safe and effective. Trial organizers, who set the standards for admission to a study, want to make certain that subjects are enough alike so that changes that occur during the test can be attributed to the drug alone. “Otherwise, it would be impossible to know, for example, whether a patient experienced a cardiac event due to a side effect of the drug under study or due to an underlying health condition,” said David Gerber, a lung cancer specialist at the University of Texas Southwestern Simmons Cancer Center.
Other researchers agree. Mikkael Sekeres, director of the leukemia program at the Cleveland Clinic’s Taussig Cancer Institute, said, “Enrolling patients with certain illness could lead to the erroneous conclusion that a flare-up of the illness is caused by the drug. This could result in a study being stopped cold or the development of that drug being killed altogether.” Bruce Johnson, a lung cancer specialist at the Dana-Farber Cancer Institute and president of the American Society of Clinical Oncology, added that, “Historically, access to clinical trials has been limited to relatively few patients, with several populations categorically excluded.”
Still, there are dramatic humanitarian problems with seriously ill patients, whose survival might be helped by participation in a trial, being screened out and denied access to an experimental drug. Pancreatic cancer patient Carly Bastiansen, 29, said, “Participating in a clinical trial is really my only chance at living longer. To have had that option taken off the table was devastating.” She died in November.
Sekeres acknowledged, “Everyone thinks it’s time to take a hard look at eligibility criteria, especially doctors who have to look their patients in the eye… and explain to them that they aren’t eligible to participate.” Rafat Abonour, a multiple myeloma specialist at the Indiana University Simon Cancer Center, added that drug companies and researchers try to include “relatively healthy cancer patients “ in their studies since “they’re most likely to do well. We don’t really know how tolerable or effective a drug in clinical trials will be in the patients we see day to day, because they so often have other health problems.”
Yet the criteria for clinical trials keep becoming more numerous and demanding. The Journal of Thoracic Oncology cited a 50-percent increase in eligibility requirements during the last 30 years.
The American Society of Clinical Oncology and the lay group Friends of Cancer Research have jointly issued a proposal for widening and relaxing admission criteria in cancer-related clinical trials. Age limitations, HIV diagnosis, organ failure, multiple cancer diagnoses and metastasis to the brain would all be removed as causes for exclusion for trials.
Richard Pazdur, director of the Oncology Center at the FDA, said, “The FDA has been actively encouraging sponsors to take a more thoughtful approach to determining eligibility criteria and to re-evaluate the practice of simply duplicating criteria from one trial to the next.”