A drug pipeline is the set of drug candidates that an individual pharmaceutical company or the entire pharmaceutical industry collectively has under discovery or development at any given point in time. The drug pipeline is also sometimes restricted to a particular drug class or extended to mean the process of discovering drugs. The R&D pipeline involves various phases that can broadly be grouped in 4 stages: discovery, pre-clinical, clinical trials and marketing. Pharmaceutical companies usually have a number of compounds in their pipelines at any given time.
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