How Long Does Each Clinical Trial Last?

How long a clinical trial lasts depends on several factors, like how long it takes to find people to take part in the trial and the main questions the trial is trying to answer. For example, clinical trials in cancer can take years to see if the treatment does what it is meant to do. The length of the trial also varies by trial phase.

Phase 1 clinical trials study the safety and dosage of an investigational treatment. This is the first time the investigational treatment is studied in people. Most phase 1 trials take less than a year. If the trial is studying the effects of only a single dose, it may take just a few months.

Phase 2 clinical trials look at how well an investigational treatment works (efficacy) for a specific condition or disease in a larger group of people. They also keep checking for safety and side effects. Phase 2 trials can last up to 2 years.

Phase 3 clinical trials study the longer-term effects of an investigational treatment in a larger group of people who have the condition or disease. These trials continue to check the safety of the investigational treatment. Phase 3 trials may last up to 4 or 5 years.

Phase 4 clinical trials happen after a treatment has been approved by a government regulatory agency for use by the public. These trials may last for several years to learn about the risks and benefits of the treatment over time, as well as the best way to use it.

A participant’s time in a clinical trial is often shorter than the full trial. For example, someone may complete a clinical trial in 2 years, but the entire trial might take 4 years to complete. This is because participants join the clinical trial at different times.

Find an Astellas Clinical Trial Near You

Search Astellas Clinical Trials to see if any might be a match for you or for someone you care about.