United States Department of Veterans Affairs
VA National HIV/AIDS Website

What is a Clinical Trial?

for Veterans and the Public

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What is a clinical trial?

A clinical trial is a research study that tests a new medicine to see if it is safe and works well. When a new medicine (or drug) is first developed, you cannot get it by prescription. Researchers must first test it in a laboratory with animals. Then, they must do a clinical trial in a hospital or clinic to test it in people. They test it to see if it is safe and to see how much of the medicine (or what dose) is enough to work.

The Food and Drug Administration (FDA)Link will take you outside the VA website. is a government agency that decides if a new drug is safe enough to give to patients by prescription. It looks at the results of the clinical trials to make this decision. Testing drugs for HIV is very important, and clinical trials are a way to find new and better medicines. All medicines that you can now get to treat HIV were first tested in clinical trials.

Clinical trials follow a set of rules called a protocol. The protocol says who can participate, how long the study is, and which tests need to be done.

Clinical trials are managed by doctors and are usually run by nurses or other health care professionals. The clinical trial staff will follow your progress closely and can help tell your regular doctor what is happening with your treatment.

Trials are also checked by an institutional review board (IRB). This is a group of people who reviews the clinical trial regularly to protect your rights, safety, and well-being.

When you are in a clinical trial, you may need to see the doctor more often and sometimes stay overnight in the hospital. This is because they want to check the effects of the medicine carefully. Because clinical trials are research, they will often test the real drug against a placebo (or sugar pill). You may not know if you are taking the medicine or the placebo until the clinical trial is over.