Author Archives: Todd Coffey, PhD

A Statistical Approach to Assess and Justify Potential Product Specifications

As stated in ICH Q6B, specifications are critical quality standards that are both proposed and justified by drug product manufacturers. Xiaoyu et al. provide information on several statistically based strategies to establish specification acceptance criteria (SAC) (1). Here we address an alternative approach to relate proposed SAC for quantitative data to relevant lot history. In particular, proposed SAC can be derived in part by using calculated limits for which the lower bound of an approximate 95% confidence interval for the…

Biological Assay Qualification Using Design of Experiments

In 2012, the United States Pharmacopeia (USP) published a complementary set of three guidance documents on the development, analysis, and validation of biological assays (1,2,3). USP chapter recommends a novel, systematic approach for bioassay validation using design of experiments (DoE) that incorporates robustness of critical parameters (2). Use of DoE to establish robustness has been reported (4,–5), but to our knowledge its use in qualification or validation protocols for assessing assay accuracy, precision, and linearity is not described in literature.…