Preclinical research involves testing a drug before sending it to clinical trials. In vitro (test tube or cell culture) and in vivo(animal)investigations are used to assess a wide range of drug dosages, and Insilco profiling using computer models of drug–target interactions are also available.
Clinical research aims to improve disease knowledge, diagnostic methods, and innovative medicines or medical equipment to provide improved patient care. Before clinical phase to begin the researcher must go through the Investigational New Drug Process. Phase I trials are the initial evaluations of a medicine in a small group of healthy human volunteers. Phase II trials are aimed to investigate the efficacy of a medicine and to continue the Phase I safety assessments on larger groups of patients. These assessments are done to check the efficacy, toxicity, pharmacokinetic and safety.