If your clinical trial is in Phase I through III of drug development or is a comparative bioavailability trial then these CTA requirements apply. As well, if your clinical trial involves marketed products, where the proposed use of the product in your protocol is outside the parameters of approval (Notice of Compliance/Drug Identification Number), For example, if one or more of the following is different than what’s in the approved product monograph: indication(s) and clinical use;  target patient population; route(s) of administration; dosage regimen However, investigators are not required to file a CTA for clinical trials involving marketed drugs where the investigation is to be conducted within the parameters of the approved NOC or DIN. These are considered Phase IV trials.