Bio/pharmaceutical R&D is Drug Discovery and Drug Development

Drug Discovery encompasses all scientific exploration leading up to the discovery of a clinical candidate.  The clinical candidate is a chemical or biopharmaceutical substance which can be produced in large quantity and has been shown to impact a specific disease mechanism in cellular and animal disease models, suggesting therapeutic benefit to patients.

Drug Development encompasses all scientific exploration of a clinical candidate to prove its safety and efficacy in humans and its therapeutic benefit to patients.

Drug Discovery is considered to be less routine than Drug Development (but is it?)