An Investigational New Drug Application (IND) is the FDA submission that authorizes clinical investigation of an unapproved drug or biologic in humans in the United States.
It includes preclinical safety data, manufacturing information, investigator details, and the proposed clinical protocol needed to justify human exposure. IND activation is typically required before enrollment can begin, while IRB review occurs in parallel to confirm ethical conduct and participant protections. The IND framework establishes ongoing obligations for safety reporting, protocol amendments, and regulatory communications throughout the study. IND oversight is foundational to lawful U.S. drug development and supports a structured approach to risk management across clinical phases.