Understanding Clinical Trial Phases: How Drugs Go From Dreams to Reality

Often in the news you will hear that a new treatment for breast cancer has entered a clinical trial phase. Do you know what that means? Here is some helpful information for understanding how new drugs and devices progress through trials to approved treatments.

Clinical trial phase one

This is the first time new treatments are used on humans. A small group of patients, often who have exhausted all other options, are administered the new method. They are closely monitored to see if there are any adverse side effects. The dosage is then changed based on how they react. This phase tests not if a drug works, but if it is safe for human consumption.

Photo: AdobeStock/Darren Baker
Photo: AdobeStock/Darren Baker

Clinical trial phase two

This phase often includes 25-100 people. The new treatment is given to more participants than in phase one in order to identify any side effects that might occur across a broader range of people.

Clinical trial phase three

During phase three, a large group of individuals, typically several hundred, take part in a randomized, double-blind study. Patients are given the new drug or device or current standards of care for the disease. This phase focuses on determining if the new treatment is better than what is currently available. Participants are often spread throughout the country or even the globe and neither they or their doctors know which treatment they have been given. This allows for unbiased reporting of the treatment’s effects.

Photo: AdobeStock/monticellllo
Photo: AdobeStock/monticellllo

Once these phases have been completed and the new method has been deemed safe, it is submitted for approval to the Food and Drug Administration. If the FDA approves it, the drug or device will become available to the public. That does not mean all trials are complete, often the pharmaceutical company or agency sponsoring the clinical trial will complete several more phases in order to test the treatment’s long-term effects. If you are interested in partaking in a clinical trial your doctor may have suggestions for potential options.

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