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Clinical Research Basics

Clinical trials are research studies performed that aim to evaluate a medical, surgical, or behavioral intervention. They help researchers evaluate a new drug or medical device to determine if it is:

  • Safe
  • Effective
  • Better than the standard or current treatment

Clinical trials also test methods of early detection of diseases, prevention of health conditions, and may also look at ways to improve the quality of life for people living with a life-threatening disease or a chronic health condition. Clinical trials may also study the role of caregivers or support groups.

There are two main types of clinical research studies:

  • Observational studies observe people in normal settings. Patients are treated based on normal clinical decisions if needed. Participants are monitored over a period of time and the study team collects and reviews the data gathered. For example, for a set period of time, researchers may collect data of older adults through medical exams, tests, or questionnaires to learn more about the effects of different lifestyles on cognitive health.
  • Interventional clinical trials take action to prevent, better understand, or treat a disease. Researchers test the safety and effectiveness of a new drug or other treatment. Interventional clinical trials follow strict rules to protect patients.

How do Clinical Trials Work?

The idea for a clinical trial often starts in the laboratory. After researchers test new treatments or procedures in the lab, the most promising treatments are moved into clinical trials. As new treatments move through a series of steps called phases, more information is gained about the treatment, its risks, and its effectiveness.

Clinical trials are done in four phases to test a treatment or, in the case of a new drug, find the appropriate dosage, and look for side effects. The FDA typically requires Phase I, II, and III trials to be conducted to determine if the drug can be approved for clinical use and continue to monitor its effects.

Phases of Clinical Trials

Phase I: Is it safe?

The main goal is to see if the treatment is safe.

People in Phase I studies can be healthy or have a disease.

Phase II: Does it work?

Once a treatment is safe, then a Phase II study is done to see if the treatment works.

Phase II studies usually have more participants than Phase I studies.

Phase III: Is it better than what we currently have?

A Phase III study compares a new treatment with a current treatment to see which is safer and works better.

Phase III studies have a large number of participants, sometimes thousands.

After a Phase III study shows that a treatment works and is safe, then the Food and Drug Administration (FDA) reviews it for approval.

Phase IV: What else can happen?

After FDA approval and the treatment is being used, researchers may do a Phase IV study.

Phase IV studies look at whether the treatment is useful for other conditions or if it has any long-term side effects.

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