Reproductive toxicity studies for biologics are built around risk questions, not a preset list of tests, with species and endpoints chosen for each drug. The FDA evaluates biologic reproductive risk by first confirming a pharmacologically relevant species, then assigning each unanswered reproductive question to the study and endpoints most able to answer it. Evolocumab shows how a hamster mating study and a monkey repeat-dose study each covered different parts of the same risk chain, instead of repeating one fixed design. Why reproductive toxicity studies for biologics start with species relevance For small molecules, reproductive toxicity testing follows a fairly standard sequence. Fertility and early embryonic development come first, then embryo-fetal…