How an Experimental Drug Becomes an Approved Therapy

Ever wondered what it takes for a potential cystic fibrosis drug to become approved by the U.S. Food and Drug Administration? Here's an explanation of the four phases of clinical research.

Oct. 12, 2015 | 2 min read
Christina Roman

This is an exciting time for cystic fibrosis research, with more than two dozen potential drugs being tested in clinical trials.

But in order for any new drug to become available to the public, it must pass through three phases of clinical trials to show that it is safe and effective in treating the disease, and receive approval by the U.S. Food and Drug Administration (FDA). If the FDA approves the drug, it will continue to be monitored for safety and effectiveness in what is known as a Phase 4 study.

Here's a breakdown of the questions that researchers try to answer, the number of participants needed and the time per participant for each phase of research.


Because there are so many promising new research opportunities, as many people with CF as possible are needed to participate in clinical trials.

Check out our Drug Development Pipeline to find out where new drugs are in the clinical trial process.

This site contains general information about cystic fibrosis, as well as personal insight from the CF community. Opinions and experiences shared by members of our community, including but not limited to people with CF and their families, belong solely to the blog post author and do not represent those of the Cystic Fibrosis Foundation, unless explicitly stated. In addition, the site is not intended as a substitute for treatment advice from a medical professional. Consult your doctor before making any changes to your treatment.

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Research | Drug Pipeline | Clinical Trials

As community engagement manager for the Cystic Fibrosis Foundation, Christina works to help embed the voice of the community into the work of the Foundation. Before joining the community partnerships team Christina worked on the clinical trials team for 3 years and at Colorado Children's Hospital for 2 years supporting the CF team. She holds a master's degree in public health from the University of Colorado. Originally from Estes Park, Colo., Christina now lives in Washington, D.C., with her husband.

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