What is a Clinical Trial?
A clinical trial is a type of research study that helps scientists and physicians understand whether a new drug, device, or approach to care is safe and effective.
Every medicine or medical device that becomes available in the United States must first go through a series of carefully designed clinical trials, overseen by the U.S. Food and Drug Administration (FDA). These studies are the bridge between scientific discovery and real-world medical practice.
Clinical trials take place in phases:
Clinical research includes different types of studies, depending on the question being asked.
Pre-clinical research occurs before studies involve people and includes laboratory and animal studies designed to better understand a disease or a potential treatment.
Clinical trials that involve people may take place in phases:
Phase 1 studies are the first time a new drug or treatment is tested in people. These studies focus on safety and how the body responds.
Phase 2 studies look more closely at whether the drug has the intended effect in people with a specific condition.
Phase 3 studies involve larger groups and compare the investigational treatment to existing standards or a placebo to confirm effectiveness and monitor side effects.
Phase 4 studies occur after FDA approval and continue to gather information about long-term safety and real-world use, or additional indications.
Observational and non-interventional studies may also be conducted. These studies do not involve investigational treatments and instead collect information—such as medical history, imaging, lab results, or patient-reported outcomes—to better understand a condition over time.
Each type of study plays an important role in advancing scientific knowledge and improving future care.
Clinical trials follow strict ethical and regulatory standards. Every study must be approved by an Institutional Review Board (IRB) — an independent committee that ensures participant rights and safety are protected.
Participating in a clinical trial does not mean receiving proven treatment. Instead, it means helping researchers gather the data needed to understand whether a new therapy might one day help others.
Clinical trials are the foundation of medical progress. The commitment of volunteers and researchers working together is what makes discovery possible — turning questions into knowledge and knowledge into hope for the future.