Mefenamic acid bioequivalence assessment with a new statistical procedure

Area of Science:

• Pharmacokinetics and Pharmaceutical Sciences
• Biostatistics and Analytical Chemistry

Background:

• Assessing the bioequivalence of pharmaceutical formulations is crucial for drug efficacy and safety.
• Traditional bioequivalence methods, such as Westlake's confidence intervals and Shuirmann's t-tests, rely on specific statistical models.
• There is a need for model-independent methods to evaluate formulation similarity.

Purpose of the Study:

• To evaluate the bioequivalence of three mefenamic acid formulations using the zeta 2 index.
• To compare the performance of the zeta 2 index with established bioequivalence testing methods.
• To determine if the zeta 2 index provides comparable results to Westlake's and Shuirmann's tests.

Main Methods:

• The study utilized the zeta 2 index, a measure of distance between concentration-time curves in Hilbert space.
• This index was applied to three different mefenamic acid formulations.
• Results were compared against 90% and 95% symmetrical confidence intervals (Westlake) and two one-sided t-tests (Shuirmann).

Main Results:

• The zeta 2 index was found to be a valid measure for assessing the similarity between mefenamic acid formulations.
• Results obtained using the zeta 2 index were fully comparable to those derived from Westlake's and Shuirmann's methods.
• The zeta 2 index does not require assumptions about the underlying absorption or elimination models.

Conclusions:

• The zeta 2 index offers a robust and model-independent alternative for bioequivalence testing.
• This new approach provides results comparable to established statistical methods for pharmaceutical formulations.
• The zeta 2 index can be reliably used to determine the similarity of different drug formulations.