Drug Trial Phases

Drug Trial Phases

Any new medication or treatment plan must pass through four levels of testing to decide if it will be helpful for patients:

  • Phase I: the treatment is given to a few healthy volunteers to see if it is safe and to learn how it works in the body.
  • Phase II: the treatment is given to 100-200 patients to see if it helps to treat the disease.
  • Phase III: usually a Randomized Controlled Trial to measure how well the new treatment works compared other to options.
  • Phase IV: long-term “surveillance” after doctors start prescribing the new treatment to see if there are any long-term side effects.
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