An Investigational New Drug (IND) application is a submission to the US Food and Drug Administration (FDA) that requests permission to conduct clinical trials of a new drug or biological product in humans. An IND is required before any clinical testing of an investigational drug can begin in the US.

The purpose of an IND application is to provide the FDA with sufficient information about the investigational drug to allow the agency to assess the safety and effectiveness of the drug and to ensure that the proposed clinical trials are ethical and scientifically sound. The application must include information on the drug’s pharmacology, toxicology, manufacturing, and proposed clinical trials.

The IND application is typically submitted by the drug sponsor, which is usually a pharmaceutical or biotechnology company. The application must include the following information:

1. Preclinical data: The sponsor must provide data from animal studies that demonstrate the safety and effectiveness of the drug, as well as information about the drug’s pharmacology, pharmacokinetics, and toxicity.
2. Manufacturing information: The sponsor must provide information about the drug’s manufacturing process, including details about the chemical synthesis, formulation, and stability of the drug.
3. Clinical trial information: The sponsor must provide details about the proposed clinical trials, including the number of patients, the duration of the trials, and the endpoints that will be used to assess the drug’s safety and effectiveness.

Once an IND application is submitted, the FDA has 30 days to review the application and determine whether it is acceptable. If the FDA does not raise any objections during this period, the sponsor may begin clinical trials of the investigational drug.

An IND application is a critical step in the drug development process, as it allows researchers to begin testing the safety and effectiveness of a new drug in humans. If the clinical trials are successful, the sponsor may submit a New Drug Application (NDA) to the FDA for approval to market the drug.