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Your First Clinical Trial: What to Expect

Clinical trials have led to important medical breakthroughs, including vaccines and treatments for heart disease, diabetes, cancer, and other diseases. Here’s what you need to know before enrolling in a clinical trial.

1. Participation is voluntary

Participants can stop participating for any reason, at any time.

2. There may be some risks

The investigational treatment you receive may turn out to be no better, or worse, than the standard treatment. It may cause unpleasant, serious or even life-threatening side effects.

3. It’s a commitment

Participants may have more tests or treatments, or have to visit the place of treatment more often, than the standard treatment of care.

4. Ask questions

  • How long is the study going to last and what will I be asked to do as a participant?
  • How will treatment be given?
  • Does it involve a placebo or a treatment already on the market?
  • Do I have to pay for any part of the study? Does insurance cover these costs?
  • Will I be reimbursed for travel costs or childcare?

5. Who’s conducting the clinical trial

Who’s sponsoring the study, such as a drug company? Do the doctors or investigators have financial or special interests in the clinical study? What are the doctor’s credentials and research experiences?

6. There are different types of clinical trials

  • Treatment trials test new therapies such as new drug combinations or new surgical approaches.
  • Prevention trials research ways, including medicines, vitamins, vaccines or lifestyle changes, to prevent disease.
  • Diagnostic trials research better tests or procedures for diagnosing specific diseases or conditions.
  • Screening trials identify the best way to detect certain diseases or health conditions.
  • Quality of Life trials, also called Supportive Care trials, look at ways to improve comfort and the quality of life for people with chronic illness.

7. Clinical trials are conducted in phases

  • Phase I: researchers test a new drug/treatment in a small group of 20-80 people for the first time, looking at safety, safe dosing and side effects.
  • Phase II: the study drug/treatment is given 100-300 people to see if it’s safe and effective.
  • Phase III: the study/drug treatment is given to 1,000-3,000 people to confirm its effectiveness, monitor side effects and compare it to commonly used treatments.
  • Phase IV: post marketing studies on drug’s risks, benefits, and optimal use.

8. They’re monitored

All clinical trials in the U.S. must be approved and monitored by an Institutional Review Board (IRB), an independent committee of physicians and community advocates, ensuring risks are low and worth potential benefits.

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