Deep brain stimulation — a novel surgical procedure — is emerging as a treatment of last resort for people diagnosed with neuropsychiatric disorders such as severe obsessive-compulsive disorder. The US Food and Drug Administration granted a so-called humanitarian device exemption to allow patients to access this intervention, thereby removing the requirement for a clinical trial of the appropriate size and statistical power. Bypassing the rigors of such trials puts patients at risk, limits opportunities for scientific discovery, and gives device manufacturers (...) unique marketing opportunities. We argue that Congress and federal regulators should revisit the humanitarian device exemption to ensure that it is not used to sidestep careful research that can offer valuable data with appropriate patient safeguards. (shrink)