The Food and Drug Administration (FDA or Agency) is announcing the availability of a draft guidance for industry entitled “Postmarketing Studies and Clinical Trials:  Determining Good Cause for Noncompliance with Section 505(o)(3)(E)(ii) of the Federal Food, Drug, and Cosmetic Act.”  The Federal Food, Drug, and Cosmetic Act (FD&C Act) authorizes FDA to require certain postmarketing studies and clinical trials for prescription drugs at the time of approval or after approval if FDA becomes aware of new safety information.  This draft guidance describes the factors FDA considers when determining whether an applicant has demonstrated good cause for failure to comply with the timetable for completion of studies or clinical trials required under the provisions.  This draft guidance also provides information on relevant procedures, including how an applicant should communicate with FDA regarding compliance with these required studies and trials and describes actions FDA may take for noncompliance with the requirements.