JAWAHARLAL NEHRU TECHNOLOGICAL UNIVERSITY HYDERABAD Pharm. D V Year CLINICAL RESEARCH Previous Question Paper (January/February - 2021 - R08)

An Investigational New Drug (IND) application is the mechanism by which a drug sponsor obtains permission from regulatory authorities, such as the FDA, to initiate clinical trials in humans. The primary objective of the IND is to provide sufficient data to ensure the safety of human subjects during the investigation. The application must include three main components: preclinical data, clinical protocols, and investigator information.

The preclinical section includes results from pharmacology and toxicology studies in animal models to determine the drug's potential toxicity and therapeutic index. The clinical protocols detail the study design, including the objectives, patient selection criteria, dosing regimens, and safety monitoring plans for Phase 1 trials. Finally, the application must provide evidence that the manufacturing process is capable of producing a drug substance of consistent quality and purity, known as Chemistry, Manufacturing, and Controls (CMC) information. Once submitted, the regulatory agency has 30 days to review the application; if no clinical hold is issued, the sponsor may proceed with human testing.

Drug characterization is a critical phase in the drug discovery and development process that involves the comprehensive identification and quantification of the physical, chemical, and biological properties of a drug candidate. This process ensures that the substance is well-defined before it proceeds to advanced development stages.

Key aspects of drug characterization include:

• Physicochemical properties: Determination of molecular weight, structure elucidation (using NMR, IR, and mass spectrometry), solubility, pKa, partition coefficient (logP), and polymorphism. These factors dictate the drug's stability and bioavailability.
• Biological characterization: Assessment of the drug's potency, efficacy, and mechanism of action through in vitro assays and receptor binding studies to confirm the desired pharmacological profile.
• Purity and Impurity Profiling: Identification and quantification of related substances, degradation products, and residual solvents using analytical techniques like HPLC or GC. This is essential for establishing safety specifications.
• Stability testing: Evaluating the drug's sensitivity to environmental factors such as light, temperature, and humidity to determine appropriate storage conditions and shelf life.