ABSTRACT
As indicated earlier, a stability analysis is usually performed to characterize the degradation pattern or curve of a drug product by testing a limited number of batches under appropriate storage coniditions. Since different batches of a drug product may have different degradation patterns for various reasons (e.g., different stranghts, different package types, different storage conditions), both the FDA and ICH require that at least three batches, and preferably more, be tested to allow for some estimates of batch-to-batch variability and to test the hypothesis that a single expiration dating period period (shelf-life) is justifiable for all (future) batches. The expiration dating period is determined based on a statistical confidence (or prediction) interval analysis.
