FPGEE for National Association of Boards of Pharmacy (NABP) Practice Exam

For two drugs to be considered equivalent, what is the acceptable difference in the rate and extent of absorption?

1. -10% to +10%

2. -20% to +25%

3. -30% to +30%

4. -15% to +20%

The correct answer is: -20% to +25%

For two drugs to be considered equivalent, the acceptable difference in the rate and extent of absorption is typically defined within a specific range established by regulatory authorities, such as the FDA. The correct option indicates a range of -20% to +25%. This standard means that for two formulations of the same drug to be deemed bioequivalent, the pharmacokinetic parameters (like the area under the curve (AUC) and peak serum concentration (Cmax)) must fall within that specified range. This range allows for variability in absorption between different drug formulations, acknowledging that minor differences can occur due to factors such as the manufacturing process, formulation differences, or the presence of excipients. The chosen range is widely accepted in bioequivalence studies, ensuring that the two formulations will provide similar therapeutic effects, maintaining safety and efficacy for patients. Thus, it reflects the balance between flexibility in manufacturing variability and the necessity for consistent clinical outcomes.