This paper discusses an approach for the establishment and lifecycle management of biological and biotechnology-derived product specifications. The views presented are consistent with the concept of Quality by Design (QbD), in which critical quality attributes (CQAs) are distinguished from parameters used to monitor process consistency. Specifications and the corresponding limits as applied to CQAs serve to ensure that the product is fit for use, whereas control limits are a manufacturer’s tool to monitor shifts and trends in the manufacturing process. In the current paradigm, inappropriate use of specifications creates a disincentive for continuous process understanding; more suitable approaches to analyzing development and manufacturing data are discussed. Statistical methods are presented for deriving and interpreting data against specifications that better manage the risk to the customer of receiving product with diminished safety or efficacy, as well as the risk to the manufacturer of earmarking a satisfactory lot as unacceptable. The recommendations are presented as a rational approach to setting and maintaining specifications, while recognizing that their applicability may not be suitable in all cases, given the heterogeneity of types of regulated biological and biotechnology-derived products and their unique challenges.
A SUGGESTED APPROACH FOR DEVELOPING AND MAINTAINING A TOTAL QUALITY SYSTEM
A rational approach to setting and maintaining specifications should incorporate the following fundamental principles:
On the basis of these principles, the following guidance is recommended for setting limits for biological and biotechnology-derived products.
1. Capture scientific data during development to set limits that reflect fitness for use throughout the shelf life of the product.
With the goal of setting specifications that reflect fitness for use, development studies should be performed to identify quality attributes that may be linked to clinical outcomes, and to set release limits that guarantee the quality of the product throughout its shelf life. Setting specifications in this way requires a coordinated effort among the preclinical, clinical, and nonclinical development teams. The goal of identifying quality attributes that may be linked to fitness for use may be accomplished by using sound scientific judgment and by evaluating the historical performance of products with similar quality attributes.
Preclinical studies in animals or cell culture can help assess how changes in quality attributes may affect clinical outcome. These studies form the beginning of our understanding about which quality attributes may be clinically meaningful, and also can provide a basis for setting preliminary or final limits on those attributes. Clinical studies in target populations may be designed to explore or support ranges for meaningful quality attributes, which together with preclinical experiments form the basis of specifications. Nonclinical studies on final product should be designed to explore and define the properties of the product and analytical methods under conditions that are likely to occur during manufacture, testing, handling, and product shelf life.