Ethics of phase 1 oncology studies: reexamining the arguments and data

Abstract

Phase 1 oncology trials are critical to improving the treatment of cancer. Critics have raised 2 fundamental ethical challenges about phase 1 cancer research: the paucity of benefits with substantial risks and poor-quality informed consent. Despite 3 decades of controversy about phase 1 oncology research, there is little critical analysis of the arguments or of the data relevant to these questions. Existing but old data reveal that about 5% of patients in phase 1 trials experience shrinkage of their tumor, with a 0.5% mortality rate. In some notable cases, patients in phase 1 trials have been cured or sustained long-term remissions. Limited data suggest that patients in phase 1 trials may have better quality of life than comparable patients receiving supportive care. More important, the risks and benefits of phase 1 trials are not clearly worse than risk-benefit ratios used by the US Food and Drug Administration to approve chemotherapeutic agents for clinical use. The objections based on informed consent are deficiencies of disclosure, understanding, and voluntariness. The available data do not support the claim that disclosure is deficient. Although studies evaluating patient understanding have substantial methodological problems, they demonstrate that more than 70% of patients understand that they may not directly benefit even when they hope they will personally benefit. Finally, a closer look at issues of voluntariness reveals that patients with advanced cancer who participate in phase 1 research may have a different set of values than do critics and are not coerced. Overall, it appears that phase 1 oncology trials satisfy the requirement for a favorable risk-benefit ratio and that patients who enroll provide adequate informed consent.