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

Phase II trials focus on which of the following aspects?

1. Safety and effectiveness in healthy subjects

2. Efficacy and side effects in subjects with the condition

3. Long-term effects post-approval

4. Comparative efficacy against existing treatments

The correct answer is: Efficacy and side effects in subjects with the condition

Phase II trials are primarily designed to assess the efficacy and side effects of a treatment in individuals who have the condition that the drug or intervention aims to treat. This phase follows initial safety assessments conducted in Phase I trials, where the drug is tested in healthy subjects to evaluate its safety profile. By the time a study reaches Phase II, the focus shifts to understanding how well the treatment works for patients suffering from the specific condition. During Phase II trials, researchers closely monitor not just the treatment's effectiveness in improving the condition but also the side effects that patients might experience while undergoing treatment. This dual focus on efficacy and safety is critical in determining whether the treatment should progress to larger Phase III trials, where it is tested further in a more diverse patient population. In contrast to the other options, safety in healthy subjects (which pertains to Phase I), long-term effects post-approval (related to Phase IV studies), and comparative efficacy against existing treatments (often the focus of later-stage trials) are not central to the objectives of Phase II trials. Thus, the emphasis during this phase remains squarely on both how effective the treatment is for the intended patient population and the associated side effects they may encounter during the treatment.