A clinical trial is a type of research study commonly designed to determine if a new drug or vaccine is safe and effective in humans. (Scientists first study the drug or vaccine in laboratory animals to be sure that it is safe enough to begin testing in humans.)

Anyone can volunteer for a clinical trial, but not everyone will be accepted. Every clinical trial has entry criteria, a set of rules that select exactly who can join.

Inclusion and exclusion criteria are the rules used to determine who can and cannot participate in a specific clinical trial:

Inclusion criteria are requirements that a person must meet to participate (such as CD4 cell count, viral load, age, or other laboratory values).

Exclusion criteria are factors that prevent a person from participating either for his or her safety or to make it easier to understand the study results. For example, people might be excluded for having liver problems, or if they’ve already used a drug that is being studied. Women who are pregnant or breast-feeding are usually not allowed into a study because the medication may not be safe for the baby. Often there are separate studies for pregnant women.

People are never excluded from studies because of race or income or the language they speak. In fact, HIV research programs try to enroll women and members of minority groups. 

An informed consent document must be given to every person considering joining a trial. The document includes complete information about the trial, written in easy-to-understand language. It also contains the names of people to contact if you have questions about your rights as a research participant or want to report a problem with the trial.

Make sure the following questions are answered in the consent form:

• What is the purpose of the study?
• What treatment is being studied?
• What is the schedule of required procedures?
• How long will the study last?
• What are the benefits and risks of participating?
• Will I be paid for volunteering?
• Who pays for my medical expenses while I am a participant in the study?
• Will my personal information remain confidential even after the study has ended?

A member of the research staff will explain the details of the trial to you and give you the informed consent to read. If you agree to participate in the trial, you will be asked to sign the informed consent. If any study procedures change while you are a participant, you will be asked to sign a new informed consent. Remember, you have the right to choose to drop out of the study at any time. This decision will not affect your medical care at the clinic or doctor’s office.

There is no cost to participate in a clinical trial. Trial medication is usually free and the study sponsors cover the cost of any lab tests related to the study. However, most trials expect your private insurance or Medicaid to pay for additional lab tests not required by the study and other medications you may be using.

It is important to consider that there may be a significant amount of time required to participate in a study. You may have to take time off from work or cover additional childcare expenses. Some clinical trials will pay you a set fee to compensate for your time and any additional expenses you incur in order to participate in the study, such as childcare or transportation expenses.

A placebo is commonly known as a sugar pill. It is a substance that looks identical to the trial medication (whether it is a pill, liquid, or shot) but does not contain any active drug. Placebos have no effect on the body. In a clinical trial the investigators sometimes compare an experimental drug with a placebo to determine if the experimental drug works.

If a trial you are considering uses a placebo, find out if you will eventually have a chance to get the experimental medication as part of your participation in the trial if the drug is shown to work.

No, not all studies are sponsored by the government. However, federal agencies, such as the National Institutes of Health (NIH) and the Centers for Disease Control and Prevention (CDC), sponsor clinical trials in collaboration with a variety of organizations, universities, and pharmaceutical companies. Clinical trial locations vary by study, but enrollment sites are generally a university, hospital, doctor’s office, or community clinic. 

Expanded access programs provide drugs that are not yet FDA approved, usually for free, once there is enough information to show safety and efficacy.  Expanded access programs allow the drug company an opportunity to collect information about how the drug works in very large groups of people who are not in a controlled clinical trial. In addition, expanded access programs allow people with HIV access to a new treatment before it’s available to the general public for purchase. There are usually a limited number of spots and certain requirements you must meet to be eligible for expanded access

If you feel you may benefit from an experimental treatment, but you do not meet the inclusion criteria for the clinical trial testing this treatment, you should talk to your doctor to find out if expanded access is available.

Participating in a clinical trial or an expanded access program are good ways to receive free experimental treatments for HIV, however once the drug is approved each drug company has a patient assistance program available for people who are uninsured and can not afford their medications. In addition, in the United States, every state has an AIDS Drug Assistance Program (ADAP) and a Medicaid program, which may provide you with FDA-approved medications if you qualify.