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    Clinical Trials

    Clinical trials are research studies to test drugs, devices, or other treatments and are critical to improving treatment options, increasing survival rates, and improving quality of life.

    Clinical trials are part of a long and careful process that takes years. First, doctors study a new treatment in a lab. Then they study the treatment in animals. If the new treatment shows promise, doctors then test it in people through clinical trials. All new treatments must go through the clinical trial process before being approved by the Food and Drug Administration (FDA).


    Clinical trials are typically conducted in three to four steps or phases. Knowing the clinical trial phase can tell you how much is known about the treatment and the potential benefits and risks.

    • Phase I trials: Doctors are testing if a new treatment is safe in people. They are looking to identify the highest dose that can be given without causing severe side effects. Phase I trials carry the most potential risk but can benefit patients with high-risk or treatment-resistant cancer.
    • Phase II trials: At this phase, doctors test many patients with a specific type of cancer to see if they respond to the new treatment. Usually, less common side effects are uncovered during this phase due to the larger group of patients receiving the new treatment.
    • Phase III trials: This phase is used to compare the safety and effectiveness of the new treatment against the current approved treatments.
    • Phase IV trials: After the FDA approves the new treatment, it may be watched over a long period of time in a phase IV trial. The purpose of this phase is to find more information about long-term benefits and side effects. This step is often the safest for patients since the treatment has already been studied during previous phases.
    leukemia clinical trial phases

    Deciding to join a clinical trial

    Visit our Deciding to Join a Clinical Trial webpage to learn more about the things to consider when determining if a clinical trial is a good option for you.

    Find a clinical trial

    Visit our Find a Clinical Trial webpage for more information about how to find a trial, how to know if you are eligible, and questions to ask to determine if it's right for you.

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