Clinical investigation means any experiment in which a test article, even an approved drug, is administered or dispensed to, or used involving, one or more human subjects. (FDA) The use of a marketed drug in the course of medical practice that is outside the label indications ("off-label" use or innovative care) does not in and of itself constitute investigational use of a drug, unless that use is part of an experiment or systematic investigation meeting the criteria for human subject research.
