4:24 p.m. - 2021-02-14
CLINICAL TRIAL PHASES
In developing a new drug or treatment for approval by the FDA, pharmaceutical companies typically spend several years in clinical trials to prove the new entity is safe and effective.

In the PRECLINICAL phase, the drug is tested in human cell cultures or perhaps animals in order to test for signs of toxicity.

In PHASE ZERO, about a dozen human volunteers are given small doses of the drug. Is the drug safe at those doses? Does it behave as expected?

In PHASE ONE clinical testing, less than a hundred healthy people are given the drug at ever-increasing doses. How high can the dose go without causing serious side effects? What is the best route of administration (oral, intravenous, topical)?

In PHASE TWO, several hundred people who have the medical condition which the drug is designed to treat are given the drug, again looking for safety and effectiveness. This phase of testing can go on for months or years.

In PHASE THREE, several thousand patients are given the drug in randomized and double-blind studies over several years. Is the drug as safe and effective as therapies already being used?

PHASE FOUR takes place AFTER the drug has been approved by the FDA and put on the market. Further developments that reflect on the drug's safety and effectiveness are reported to the FDA.

previous - next