This paper addresses psychological factors that might interfere with informed consent on the part of stable patients as potential early-phase clinical trial participants. Thirty-six semistructured interviews with patients who had either diabetes or gout were conducted. We investigated stable patients’ attitudes towards participating in a fictitious first-in-human trial of a novel intervention. We focused on an in-depth analysis of those statements and explanations that indicated the existence of psychological factors impairing decision-making capacity. Three main themes emerged: insufficient comprehension of the (...) inherent logic of clinical trials, the recourse to trust over comprehension, and visceral factors that override deliberative process. Overall, our results indicate a limited psychological capacity on the part of stable patients to meet the requirements of informed consent as set by Declaration of Helsinki. A redesigned informed consent procedure should take account of these psychological realities. (shrink)