ICH M3 Guidelines
Phase-0, including microdosing, approaches are governed by the ICH M3 Guidelines and summarized in Table 3 below. These guidelines have been internationally harmonized and adopted by USFDA, Europe's EMEA, and Japan's PMDA.
The guidelines use the term Exploratory Clinical Trials, which is synonymous with Phase-0, and also with Exploratory Investigational New Drug (eIND). The full name of the ICH M3 Guidelines is: GUIDANCE ON NONCLINICAL SAFETY STUDIES FOR THE CONDUCT OF HUMAN CLINICAL TRIALS AND MARKETING AUTHORIZATION FOR PHARMACEUTICALS M3(R2). Current Step 4, version dated 11 June, 2009.