Certified Research Administrator Practice Exam

Which phase of a clinical trial involves testing the efficacy of a drug or device?

1. Phase I

2. Phase II

3. Phase III

4. Phase IV

The correct answer is: Phase II

The phase of a clinical trial that primarily focuses on testing the efficacy of a drug or device is the second phase, often referred to as Phase II. During this phase, researchers evaluate how well the drug works in participants who have the condition the drug is intended to treat. This phase usually involves a larger group of participants than Phase I, allowing for a more comprehensive assessment of the drug's effectiveness as well as its safety. Phase I trials predominantly concentrate on safety, determining the safe dosage range and identifying side effects. They typically involve a small group of healthy volunteers or patients. In contrast, Phase III trials are more extensive and focus on confirming the drug's efficacy, monitoring side effects, and comparing it to commonly used treatments. Phase IV is conducted after the drug or device has been approved and is used for post-marketing surveillance to gather further safety and effectiveness data in a broader population. Thus, Phase II is specifically designed to assess efficacy, making it the correct answer in this context.