Question

The FDA criteria for bioequivalence requires that

• A. 50–150% confidence interval for C_max
• B. 90–110% confidence interval for AUC only
• C. 80–125% confidence interval for AUC and C_max
• D. 70–130% confidence interval for half-life

Hint:

Bioequivalence testing compares a test product (for example, a generic drug) with a reference product to make sure they behave similarly in the body.

Answer 1

The Correct Option is C

Concept:
Bioequivalence testing compares a test product (for example, a generic drug) with a reference product to make sure they behave similarly in the body. The two key measures compared are AUC (total drug exposure over time) and C_max (the peak concentration reached). Regulators set a statistical limit to decide if the products are "equal enough."

Step 1: The FDA accepts two products as bioequivalent if the 90% confidence interval of the ratio (test/reference) for both AUC and C_max falls completely within the range of 80% to 125%.

Step 2: This 80–125% window is applied to both AUC and C_max together, not just one of them. The other options use incorrect ranges or apply the limit to the wrong parameter (such as half-life).

Answer: Option (3) — The FDA criteria for bioequivalence requires an 80–125% confidence interval for AUC and C_max. (3)