Foreign Adversary Gain-of-Function Research Prevention Act of 2023 This bill prohibits the use of federal funds by foreign adversaries for gain-of-function research involving pathogens that could cause a pandemic. ( Gain-of-function research is defined as research that enhances the pathogenicity or transmissibility of a pathogen in mammals.) Specifically, the bill prohibits federal funds from being used to support gain-of-function research involving potential pandemic pathogens by China, Russia, Iran, North Korea, or any other designated foreign adversary. Entities that violate the bill's requirements may not receive any funds from the Department of Health and Human Services (HHS) for three years and, for the following three years, may not receive any additional HHS funds unless they agree to give advance notice about how they intend to use the funds.