A number of government public health and emergency response stakeholders2 maintain stockpiles of doxycycline3 tablets or capsules for post-exposure prophylaxis (PEP) or treatment of inhalational anthrax in the event of an anthrax emergency. States have asked FDA what would be necessary to provide confidence that stockpiled doxycycline tablets and capsules have retained their original quality (i.e., purity and potency) beyond the manufacturer’s labeled expiration date so the replacement of stockpiled product could be deferred.⁴

This document provides guidance to government stakeholders on testing to extend the expiration date—under section 564A(b) of the Federal Food, Drug, and Cosmetic (FD&C) Act⁵—of stockpiled doxycycline tablets and capsules for public health emergency preparedness and response purposes for an anthrax emergency.