Phase I clinical trials are typically conducted with which group?

• A. Small group of healthy individuals to test safety and dosage levels.
• B. Large patient population to test efficacy.
• C. Animal testing phase only.
• D. Post-marketing surveillance stage.

Answer: (A)

Phase I trials focus on safety and dosing in humans, usually with a small number of healthy volunteers. The idea is to observe how the drug behaves in the body, identify side effects, and determine a safe starting dose and dose range for further testing. This approach helps establish pharmacokinetics and tolerability before exposing larger groups to the drug in later studies. In some cases, such as certain cancer therapies or drugs that affect the immune system, Phase I may involve patients with the target condition to gather safety and dosing information directly in the relevant population. The other paths described—testing for efficacy in a large patient population, performing animal testing, or conducting post-marketing surveillance—occur in later phases or before/after human trials altogether.