Before submitting an IND application, investigators should refer to the Guidance for Clinical Investigators, Sponsors, and IRBs: Investigational New Drug Applications (INDs)— Determining Whether Human Research Studies Can Be Conducted Without an IND (PDF - 210KB) to determine whether their clinical investigations may be conducted without submitting an IND application.
The three most commonly occurring scenarios when clinical investigations may be exempted from the IND application requirements refer to certain limited situations of clinical investigations with approved marketed drugs, bioavailability or bioequivalence studies, or clinical investigations involving radioactive drugs considered safe for certain research uses. For each of these and few other scenarios, the specific criteria for exemption (PDF - 210KB) must be met.
Sponsors who are uncertain if their proposed investigation meets the criteria for IND exemption may seek advice from the FDA Review Division responsible for the relevant therapeutic area of the proposed trial. In some cases FDA staff may be able to provide this advice through informal communications (e.g., phone conversation, e-mail). In other cases FDA staff may request that the sponsor submit a summary of their proposed investigation in writing for FDA review before providing advice.
In certain cases, FDA staff may advise the sponsor to submit a full IND application for the proposed investigation for FDA review. If during that review FDA concludes the IND application meets the criteria for exemption, the sponsor will be so notified.
For additional explanation of safety reporting expectations for bioavailability and bioequivalence studies exempted from the IND application requirements refer to Guidance for Industry: Safety Reporting Requirements for INDs and BA/BE Studies (PDF - 227KB).