phase IV trial
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Related to phase IV trial: phase 2 clinical trial
phase IV trial, phase 4 trial
A clinical trial to examine long-term effectiveness and adverse effects that might occur from a treatment after the Food and Drug Administration has approved its use by the public. Such trials, involving thousands or tens of thousands of enrollee patients, are either mandated by regulatory authorities or undertaken voluntarily by a pharmaceutical manufacturer once the drug has gone to market. Often it is only in Phase IV trials that especially rare adverse effects emerge. Enrollee patients in a clinical trial should have the approval of their personal oncologist, and they should seek a second opinion (which is covered by insurance) to obtain more input on what trials to consider.
See also: trial