Clinical Trials Basics

A clinical trial is the scientific term for a test or study of a drug, therapy, surgical procedure, medical device, or of nutrition or behavioral changes in people. The tests are done to find out if the drug, therapy, procedure, etc. is safe and effective for people to use. The overall purpose of a clinical trial is to learn, not to treat patients. Before you volunteer to participate in a clinical trial, ask about any risks associated with the treatment being tested. 

Safety of Clinical Trials

Before a prospective treatment is tested on humans, it is thoroughly tested through laboratory and model studies to determine if it's safe. 

Physicians and other medical professionals run trials according to strict rules set by the federal government. The U.S. Department of Health and Human Services has two offices that identify these rules: the Food and Drug Administration (FDA) and the Office for Human Research Protections (OHRP). These agencies have good clinical practice requirements that establish rules every clinical trial must follow, such as how to conduct a study and how to protect human subjects. 

The federal government also has a policy that protects human subjects. This policy is called the “Common Rule.” It applies to all research funded by the federal government. The Common Rule says an institutional review board, or IRB, must guarantee it will provide and enforce protection for people involved in its research. An IRB reviews and approves the trial protocol before the trial can even begin. It must look at the informed consent process, benefits and risks, and how volunteers will be selected. 

Clinical Trial Phases

After a treatment is tested in the laboratory, it can go to human testing. There are four phases of human testing.

  • Phase I: Researchers test a new drug or treatment in a small group of people (20-80) for the first time to test its safety, identify the maximum tolerated dose, find a safe dosage range and identify side effects. 
  • Phase II: The drug or treatment is given to a larger group of people (100-300) to see if it is effective, to further evaluate its safety and to gather additional information regarding safe dose range. 
  • Phase III: The drug or treatment is given to large groups of people (1,000-3,000) to confirm its effectiveness, monitor side effects, compare it to commonly used treatments and collect information that will allow the drug or treatment to be used safely. 
  • Phase IV: During this phase, investigators are looking for additional information, including the drug or treatment's risks, benefits, and optimal use. This trial may occur after the drug or treatment has been approved for use by the FDA. 
  • Phase IV: Trials may be conducted to determine better dosing guidelines, new formulations, effects on different populations or new indications. 

Participating in Clinical Trials

By taking part in clinical trials, you can try a potential new treatment that may (or may not) be better than standard treatments available. Your participation may also help people who may be suffering from the same disease or condition in the future. It is important to remember that if you participate, you will be part of a group that is testing a treatment that has not yet gone through complete testing showing it to be effective and safe.

You may volunteer for any trial appropriate to your condition. However, each clinical trial has strict eligibility requirements. The investigator (physician or other medical professional who runs the trial) will make sure you meet these requirements before accepting you in the trial. 

Deciding to Participate

You are the only one who can make the decision to participate. You will receive customary medical care whether or not you choose to participate in a clinical trial. It is unethical for anyone, including your physician, to pressure you to participate. You should be given complete, accurate and balanced information about the trial. Feel free to take plenty of time to review that information, so you fully understand the benefits and risks before you decide to volunteer. 

The study investigator should explain everything about the trial before you make a decision. That's called informed consent. However, there are a number of questions you might ask before deciding if a clinical trial is right for you. 

  • What is the study trying to find out? 
  • What "phase" is the trial testing? (See above for an explanation of phases.) 
  • What kinds of tests might I have to take? 
  • How much time is involved? 
  • Will I be hospitalized? 
  • What are the costs to me? 
  • Who will pay if clinical trial funds don’t cover these costs? 
  • What are my other treatment choices? 
  • How do they compare with the treatment being studied? 
  • What side effects, if any, can I expect? 
  • How long will the trial last?

Providing Informed Consent

Informed consent means you are given complete information about a study. Before you agree to volunteer, this information will be given to you in writing, and written clearly, so you can understand it. Before you can participate, you must sign the informed consent form showing you've been given this information and understand it. Informed consent is also an ongoing process. It includes ongoing discussions regarding the risks and benefits of participating in a clinical trial. If you decide to choose standard treatment, instead of participating in a clinical trial, you should still be given complete information about your treatment alternatives, and their benefits or risks.

Informed consent is NOT a contract. You can leave the study at any time you choose. Just tell the investigator. It's important to know your decision to leave a study will not involve a penalty. You will still be able to have standard treatment appropriate for your disease or condition. You always have the right to refuse treatment or choose among treatment options, whether they involve a clinical trial, or are part of standard treatment options. The investigator may also determine that it would be in your best interests to discontinue participation before completing the clinical trial. 

Sponsors and Costs

Clinical trials are sponsored or funded by a variety of organizations or individuals. They can be sponsored by doctors, medical institutions, foundations, voluntary groups, pharmaceutical companies, or federal agencies such as the National Institutes of Health, or NIH.

Most costs in a clinical trial are covered by grants or funds contributed by the trial sponsor. Routine procedures — such as blood tests or other lab work that you would need whether or not you were participating in a trial — are usually covered by your insurance. Each trial is different, so it's best to check with the study coordinator to find out about costs.

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