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Drug Regulation

Discovery, Preclinical Testing, Phase I, Phase Ii, Phase Iii, Review By The U.s. Food And Drug AdministrationPhase IV, Time and cost

The road to drug development is a long and demanding process that can take up to 15 years. Before a substance is deemed "safe" it must go through the series of phases shown in Figure 1. These phases are called: discovery; preclinical testing (in animals); phase I; phase II; phase III; review by the U.S. Food and Drug Administration (FDA); and phase IV.

During Phase IV the drug becomes available for physicians to prescribe, but the manufacturer must continue to submit reports to the FDA that evaluate the effectiveness of the drug, monitor drug interactions, provide data that compare the drug with other drugs that are used for the same purpose, evaluate the cost-effectiveness of the drug, and provide long-term safety and efficacy data. This ongoing monitoring is called post-marketing surveillance.

From discovery to FDA approval of a drug takes about fifteen years and costs about $500 million. From the 5,000 to 10,000 new chemicals that are screened, about two hundred and fifty enter preclinical testing. Of this 250, only five enter clinical testing, and only one is approved and marketed.



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