The Food and Drug Administration (FDA or Agency) is announcing the availability of a final guidance for industry entitled “Testicular Toxicity: Evaluation During Drug Development.” The guidance addresses nonclinical findings that may raise concerns of a drug-related adverse effect on the testes, clinical monitoring of adverse testicular effects early in clinical development, and the design and conduct of a safety clinical trial assessing drug-related testicular toxicity. The guidance is intended to assist sponsors developing drugs and therapeutic biologics regulated within the Center for Drug Evaluation and Research to identify nonclinical signals of testicular toxicity and to evaluate the potential for such toxicity in humans. This guidance finalizes the draft guidance of the same name issued on July 17, 2015.