Recent FDA warning letters to Ambix Laboratories, Finemost Corp., Liquid Health Inc. and Primarch Manufacturing Inc. demonstrate that some supplement manufacturers continue to fall down on ingredient identity testing, a fundamental tenet of the good manufacturing practices final rule. Those firms all “failed to conduct at least one appropriate test or examination to verify the identity of a component that is a dietary ingredient, prior to its use,” the agency said.
This has become the most violated provision of the regulation, according to FDA’s top dietary supplements official, Daniel Fabricant. He...