Preclinical stage biopharmaceuticals are drugs that have been developed and tested in laboratory and animal studies, but have not yet been tested in humans. This stage of development is critical for determining the safety and efficacy of a drug before it can be tested in humans. During preclinical studies, researchers evaluate the drug’s pharmacokinetics, pharmacodynamics, toxicity, and other properties. The results of these studies are used to determine whether the drug is safe and effective enough to move on to clinical trials.