part_subject: "INVESTIGATIONAL NEW DRUG APPLICATION"
subpart_code: "E"
subpart_subject: "Drugs Intended to Treat Life-threatening and Severely-debilitating Illnesses"
section_number: "312.85"
section_subject: "Phase 4 studies."
cfr_reference: "21 CFR 312.85"
title_name: "Title 21"
title_subject: "Food and Drugs"
parts_covered: "Parts 300 to 499"
revised_date: "Revised as of April 1, 2019"
publication_date: "As of April 1, 2019"
contains_description: "Containing a codification of documents of general applicability and future effect"
publication_info: "Published by the Office of the Federal Register National Archives and Records Administration as a Special Edition of the Federal Register"
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Concurrent with marketing approval, FDA may seek agreement from the sponsor to conduct certain postmarketing (phase 4) studies to delineate additional information about the drug's risks, benefits, and optimal use. These studies could include, but would not be limited to, studying different doses or schedules of administration than were used in phase 2 studies, use of the drug in other patient populations or other stages of the disease, or use of the drug over a longer period of time.