Clinical Trials 101
Clinical research is medical research that involves people like you. When you volunteer to take part in clinical research, you help doctors and researchers learn more about diseases and improve health care for people in the future. Clinical research includes all research that involves people.
Types of clinical research include:
- Epidemiology, which improves the understanding of a disease by studying patterns, causes, and effects of health and disease in specific groups.
- Behavioral, which improves the understanding of human behavior and how it relates to health and disease.
- Health services, which looks at how people access health care providers and health care services, how much care costs, and what happens to patients as a result of this care.
- Clinical trials, which evaluate the effects of an intervention on health outcomes.
Video: Why Participate in Clinical Trials?
- What is informed consent?
- What are the phases of clinical trials?
- What is inclusion and exclusion criteria?
- How does a study drug come to fruition?
Informed consent is the process of providing you with key information about a research study before you decide whether to accept the offer to take part. The process of informed consent continues throughout the study. To help you decide whether to take part, members of the research team explain the details of the study. If you do not understand English, a translator or interpreter may be provided.
The research team provides an informed consent document that includes details about the study, such as its purpose, how long it’s expected to last, tests or procedures that will be done as part of the research, and who to contact for further information. The informed consent document also explains risks and potential benefits. You can then decide whether to sign the document. Taking part in a clinical trial is voluntary and you can leave the study at any time.
Clinical trials are conducted in a series of steps called “phases.” Each phase has a different purpose and helps researchers answer different questions.
Phase I trials:
- Researchers test a drug or treatment in a small group of healthy volunteers (20–80) for the first time.
- The purpose of Phase I is to study the drug or treatment to learn about safety and identify side effects.
- Investigators tend to look for the best way to administer the drug/therapy such as orally, intravenously, or topically.
Phase II trials:
- The new drug or treatment is given to a larger group of people (100–300) to determine its effectiveness and to further study its safety.
- Volunteers receiving the drug/therapy may be compared to similar volunteers receiving a different treatment, usually a placebo or other treatment.
- The drug is also given to volunteers with a certain condition/disease to determine its effectiveness.
Phase III trials:
- The experimental drug or treatment is administered to large groups of people (1,000–3,000) to confirm its effectiveness.
- Monitor side effects; compare it with standard or equivalent treatments.
- Clinical trials gather more information about a drug’s safety and effectiveness by studying different populations, and dosages by using the drug in combination with other drugs.
Phase IV trials:
- A phase of research to describe clinical trials occurring after the FDA has approved a drug for marketing.
- Phase IV studies include post-market requirements and commitment studies that are required or agreed to by the study sponsor.
- These trials gather additional information about a drug’s safety, efficacy, or optimal use.
- The reasons that a person can/cannot participate in a clinical trial.
- The sponsor usually are the ones who create these guidelines for safety reasons.
- These criteria are usually age, gender, health status, no abnormal findings of clinical relevance at screening.
- The sponsor develops a new therapy in their laboratory.
- They test the new therapy on animals for toxicities.
- Apply for an Investigational New Drug Application to the FDA.
- The therapy will 1st go through Phase I and Phase II of a clinical trial for testing.
- At the end of Phase II, the FDA and sponsor discuss how large-scale the study will be in Phase III.
- Phase III of a clinical study will typically have thousands of participants to gather more robust data.
FDA New Drug Application
- The sponsor submits a New Drug Application to the FDA for approval.
- Once approved, the FDA inspects all the facilities where the new therapy will be manufactured.
- This occurs in Phase IV of a clinical trial.
- The sponsor continues to monitor all serious unexpected adverse events.
- Once the FDA approves a therapy, the post-marketing monitoring begins. Typically includes a requirement for the sponsor to submit a safety report to the FDA periodically.
Click here for a complete glossary of terms.
Visit the National Institutes of Health (NIH) for more information.
Click here to view the Alpha-1 Clinical Trial Search Engine.
Click here for more information about financial assistance for clinical trials.