This document outlines the content requirements for an Investigational New Drug (IND) application submitted to the FDA. It describes the general content that must be included in an IND according to FDA regulations, including an introductory statement, investigator's brochure, clinical study protocols, and detailed information on the drug's chemistry, manufacturing, and controls. The level of detail required varies depending on the study phase and type of investigation. The primary purpose of an IND is to provide investigators and regulators with sufficient information on a drug's safety and study plans to ensure the protection of human subjects.