Controlling Brain Cells With Light: Ethical Considerations for Optogenetic Clinical Trials

Optogenetics is being optimistically presented in contemporary media for its unprecedented capacity to control cell behavior through the application of light to genetically modified target cells. As such, optogenetics holds obvious potential for application in a new generation of invasive medical devices by which to potentially provide treatment for neurological and psychiatric conditions such as Parkinson's disease, addiction, schizophrenia, autism and depression. Design of a first-in-human optogenetics experimental trial has already begun for the treatment of blindness. Optogenetics trials involve a combination of highly invasive genetic and electronic interventions that results in irreversible and permanent modifications of an individual's nervous system. Given its novelty, its uncertain benefit to patients, and its unique risk profile of irreversible physiological alteration, optogenetics requires a reassessment of the ethical challenges for protecting human participants in clinical trials, particularly at formative stages of clinical evaluation. This study explores the evolving ethical issues surrounding optogenetics’ potential harm to participants within trial design, especially focusing on whether Phase 1 trials should incorporate efficacy as well as safety endpoints in ways that are fair and respectful to research trial participants.

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