Significance levels for stability pooling test: a simulation study.
Shelf life of a drug product is defined as the length of time under specific conditions of storage that the product will remain within specifications established to ensure its identity, strength, quality, and purity. The objective of an new drug application (NDA) stability study is to collect and evaluate the evidence in support of the sponsor-proposed shelf life. The proposed shelf life is supported when each batch of the drug products in the study has shelf life no shorter than the proposed shelf life. When the value of the batch mean changes linearly, sometimes batches of the same product may share the same slope or regression line. In practice, batches are pooled to have a common estimate of slope or regression line when there is no significant difference in slope or regression line. Such practice is often applied in pooling across levels of a design factor such as package or strength in a stability study designed with multiple factors. However, falsely pooling different slopes or intercepts may increase false positive rates on the decision of approval for the proposed shelf life. The proposed algorithm used with the simulation technique tries to reduce false pooling rates for testing slope or intercept differences in order to bring down the false positive rates on the decision of approval for the proposed shelf life to the prespecified Type-I error rate of 5 or 10%.
Chen
Wen-Jen
WJ
Division of Biometrics II, HFD-715, Center for Drug Evaluation and Research, FDA, Rockville, Maryland 20857, USA. chenw@cder.fda.gov
Tsong
Yi
Y
D000465:Algorithms; D003198:Computer Simulation; D004355:Drug Stability; D004356:Drug Storage / Q000592:standards / Q000706:statistics & numerical data; D015233:Models, Statistical; D013997:Time Factors