The earliest point in the drug development process at which the weight of evidence suggests that it is ‘reasonably likely’ that the key attributes for success are present and the key causes of failure are absent (Cartwright et al 2010). The interpretation of this definition, however, is context dependent. For industry, POC almost always applies to clinical trials. POC studies are usually small and designed so as to provide early statistical evidence allowing drug developers to make the decision whether or not to proceed into larger, more expensive Phase 2b or 3 clinical trials. To the academic researcher however, POC often represents the results of mechanistic in vitro studies, or at best, studies in an animal model. While the scientific rationale may be proved, other questions that are important in the broader drug development pipeline are often not addressed, such as safety, efficacy, dosing regime, cost of goods, and commercial and regulatory issues that could threaten the ultimate success of a novel drug.
