Content uniformity testing: suitability of different approaches for marketed low dose tablets

Abstract

Context: Content uniformity (CU) testing was developed and improved to control the effectiveness and safety of dosage units. Many modifications of compendial CU test have been introduced and several alternatives have been suggested.Objectives: This study aims to evaluate the degree of suitability of current USP CU test for low dose tablets and to compare the performance of the current test with that of the former USP27-NF22 and other alternatives for different sample sizes.Methods: All locally marketed risperidone (RSP) tablets were analyzed using newly developed and validated isocratic UPLC method. The CU results were statistically analyzed in groups with sample sizes comparable to the USP sampling plans.Results: Seven out of eleven products failed the different requirements of the former and current USP <905>chapters as well as of several alternative CU tests with several substantial deviations.Conclusion: The current USP <905> chapter was found to have some deficiencies that allowed such failed products to exist in the market. The dependence of compendial CU test on two-staged sampling plan and the use of arithmetic mean to calculate the reference and acceptance values were obvious shortcomings.