CRO clinical research does not just involve drug development; it also includes preclinical studies of plant extracts, nutritional supplements and enzymes. These studies may focus on the role of these substances in a specific type of disease or the effect of these substances on the body. It may also include studies to test the safety and effectiveness of an ingredient as an antioxidant, antimicrobial or anti-mutagen. Some studies may seek to investigate the effect of a chemical compound or molecule on cellular functions.

CRO preclinical research has been helpful to a number of pharmaceutical companies, because such studies can help determine the potential effectiveness of a specific drug or chemical and can help determine the safety of a substance. A CRO study will also be able to assess the impact of a drug or chemical on the ability of an animal to develop healthy tumors. By understanding the molecular mechanisms by which a drug or chemical works, these studies can help in the development of drugs that can target the causes of the disease and not just its symptoms.

CRO preclinical research, like any other type of preclinical research, may sometimes require the participation of pharmaceutical companies in providing the necessary resources or equipment needed to conduct the studies. These companies may need to conduct the necessary experiments or provide samples and animals, or pay for the cost of having animals in the laboratory for the duration of the studies.