What is done in the preclinical stage of drug development?

• A. Healthy volunteers are used to determine drug tolerance and toxicity.
• B. NDA submission occurs after preclinical.
• C. Animal pharmacology and toxicology data are obtained to determine safety and efficacy.
• D. Phase 1 trials are conducted.

Answer: (C)

In the preclinical stage, the main work is to gather animal pharmacology and toxicology data to judge safety and potential efficacy before testing in humans. This involves studying how the drug behaves in a living system (pharmacokinetics and pharmacodynamics) and screening for adverse effects in animals. The goal is to identify any major safety concerns, understand dosing margins, and establish a starting point for first-in-human studies, which supports filing an Investigational New Drug (IND) application.

Healthy volunteers are used later in development (Phase I) to assess safety and tolerability in people, not in preclinical work. NDA submission happens after clinical trials when testing in humans has been completed and safety and efficacy data are compiled. Phase 1 trials are human studies conducted after preclinical work to evaluate safety and dosing.