Association of Clinical Research Professionals (ACRP) Certified Professional Practice Exam

What phase of clinical research involves dose-tolerance, single/multiple dose PK, and drug interaction studies?

1. Phase 1

2. Phase 2

3. Phase 3

4. Phase 4

The correct answer is: Phase 1

Phase 1 of clinical research is primarily focused on assessing safety, tolerability, and pharmacokinetics (PK) of a drug in humans. During this phase, researchers conduct studies to determine the optimal dosage range and how the drug behaves in the body, including absorption, distribution, metabolism, and excretion. Dose-tolerance studies are essential at this stage, as they help identify the maximum tolerated dose, which is crucial for ensuring patient safety in subsequent phases. Single and multiple dose pharmacokinetic studies are conducted to understand how the drug concentration varies in the bloodstream over time after administration, providing insights into the drug's dosing regimen. Additionally, drug interaction studies during Phase 1 can reveal how the investigational drug might interact with other medications, helping to establish safe administration practices and predict potential adverse effects when combined with commonly used therapies. This focus on establishing initial safety and proper dosing forms the foundation for later phases of clinical research, where the emphasis shifts to effectiveness and broader patient populations.