Clinical Trial Phases


Developers of drugs, biologicals, and medical devices must ensure product safety, demonstrate medical benefit in people, and mass produce the product. Preclinical development starts before clinical trials and the main goals are to determine safety and effectiveness of the intervention. If preclinical studies show that the therapy is safe and effective, clinical trials are started. Clinical trial phases are steps in the research to determine if an intervention would be beneficial or detrimental to humans and include Phases 0, I, II, III, IV, and V clinical studies. Understanding the basis of clinical trial phases will help researchers plan and implement clinical study protocols and, by doing so, improve the number of therapies coming to market for patients.

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Mahan, V. (2014) Clinical Trial Phases. International Journal of Clinical Medicine, 5, 1374-1383. doi: 10.4236/ijcm.2014.521175.

Conflicts of Interest

The authors declare no conflicts of interest.


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