- Clinical Trials: What You Need to Know
- Why do we need clinical trials?
- What happens before a clinical trial starts?
- Some facts about clinical trials to keep in mind
- What are the phases of clinical trials?
- Phase 0 clinical trials: Exploring if and how a new drug may work
- Phase I clinical trials: Is the treatment safe?
- Phase II clinical trials: Does the treatment work?
- Phase III clinical trials: Is it better than what’s already available?
- Submission for FDA approval: New drug application (NDA)
- Phase IV clinical trials: What else do we need to know?
- Who sponsors and runs clinical trials?
- Should I think about taking part in a clinical trial?
- Answers to some common questions about clinical trials
- Other questions you should ask your research team
- How are study participants protected?
- What’s out there? Finding clinical trials
- How do I figure out which study is for me?
- What about cost? Will my insurance cover it?
- Private insurers and the new health care law
- What would it be like to be in a clinical trial?
- What if I’m not eligible for a clinical trial?
- Summing it all up
- To learn more
Phase IV clinical trials: What else do we need to know?
Drugs approved in phase III trials are often watched over a long period of time in phase IV studies. Even after testing a new medicine on thousands of people, the full effects of the treatment may not be known. Some questions may still need to be answered. For example, a drug may get FDA approval because it was shown to reduce the risk of cancer recurrence. But does this mean that those who get it are more likely to live longer? Are there rare side effects that haven’t been seen yet, or side effects that only show up after a person has taken the drug for a long time? These types of questions may take many years to answer, and are often addressed in phase IV clinical trials.
Key points of phase IV clinical trials:
- Phase IV studies look at drugs that have already been approved by the FDA. The drugs are available for doctors to prescribe for patients, but phase IV studies are needed to answer important questions.
- May involve at most, a few tens of thousands of people.
- The safest type of clinical trial because the treatment has already been studied a lot and used in possibly millions of people. Phase IV is looking at safety over time.
- These studies may also look at other aspects of the treatment, such as quality of life or cost effectiveness.
You can get the drugs used in a phase IV trial without enrolling in a study. And the care you would get in a phase IV study is very much like the care you could expect if you were to get the treatment outside of a clinical trial. But in phase IV studies you are helping researchers learn more about the treatment and doing a service to future patients.
Last Medical Review: 09/25/2014
Last Revised: 10/31/2014