ABSTRACT
This chapter aims to provide principles for assessing the comparability of biotechnological/biological products before and after changes are made in the manufacturing process for the drug substance or drug product. Manufacturers of biotechnological/biological products frequently make changes to manufacturing processes of products both during development and after approval. A determination of comparability can be based on a combination of analytical testing, biological assays, and, in some cases, nonclinical and clinical data. The goal of the comparability exercise is to ascertain that pre- and post-change drug product is comparable in terms of quality, safety, and efficacy. The battery of tests for the comparability exercise should be carefully selected and optimized to maximize the potential for detecting relevant differences in the quality attributes of the product that might result from the proposed manufacturing process change. Contaminants should be strictly avoided and/or suitably controlled with appropriate in-process acceptance criteria or action limits for drug substance or drug product.
