Clinical Trials

Drugs and treatments are developed from laboratory experiments. Clinical research is usually conducted in a series of trials that become progressively larger. Carefully conducted clinical trials are the fastest and safest way to find treatments that work.

Once researchers test new therapies or procedures in the laboratory and get promising results, they begin planning Phase I clinical trials. New therapies are tested on people only after laboratory and animal studies show promising results.

A Phase I clinical trial is directly built upon basic and animal research and is primarily used to test the safety of a therapy for a particular disease or condition and to estimate possible usefulness in a few human subjects.

A Phase II clinical trial usually involves many subjects at several different centers and is used to test safety and efficacy on a broader scale, to test different dosing for medications or to perfect techniques for surgery, and to determine the best methodology for the bigger Phase III clinical trial to come.

A Phase III clinical trial often involves many centers and sometimes several hundred subjects. The trial usually has two patient groups who receive different treatments, but all other standard care is the same. The trial may compare two treatments, or, if there is only one treatment to test, patients who do not receive the test therapy receive instead a placebo (dummy drug).

Many Phase III trials are called double-blind, randomized clinical trials. Double-blind means that neither the subjects nor the doctors treating the subjects and determining the response to the therapy know which treatment a subject receives. Randomization refers to the placing of subjects into one of the treatment groups in a way that can't be predicted by the patients or investigators. These clinical trials usually involve many investigators and take many years to complete.

Most treatments for general use come out of Phase III clinical trials. After one or more phase III trials are finished, and if the results are positive for the treatment, the investigators can petition the FDA for government approval to use the drug or procedure to treat patients. Once the FDA approves the treatment, doctors throughout the country can prescribe it.

Protections for people in clinical trials

The government has strict safeguards to protect people who participate in clinical trials. Every clinical trial in the U.S. must be approved and monitored by an Institutional Review Board (IRB) to make sure the risks are as low as possible and are worth any potential benefits. An IRB is an independent committee of physicians, statisticians, community advocates, and others that ensures that a clinical trial is ethical and the rights of study participants are protected.

Informed consent

Informed consent is the process of learning the key facts about a clinical trial before you decide whether or not to participate. These facts include:

    * Why the research is being done.       
    * What the researchers want to accomplish.       
    * What will be done during the trial and for how long.       
    * What risks are involved in the trial.       
    * What benefits can be expected from the trial.       
    * What other treatments are available.       
    * The fact that you have the right to leave the trial at any time.

If you are considering joining a clinical trial, the research staff will give you informed consent documents that include the details about the study. Since joining a clinical trial is an important decision, you should ask the research team any questions you may have about the study and the consent forms before you make a decision.

Remember informed consent is more than signing a form. It is a process that continues through the study. You should feel free to ask the research team questions before, during, and after the study. Informed consent continues as long as you are in the study.

Who can participate in a clinical trial?

All clinical trials have guidelines about who can get into the program. Guidelines are based on such factors as age, type of disease, medical history, and current medical condition. Before you join a clinical trial, you must qualify for the study. Some research studies seek volunteers with illnesses or conditions to be studied in the clinical trial, while others need healthy volunteers. Healthy volunteers participate in Phase I trials, vaccine studies, and trials on research on preventive care for children or adults.

It is important to note that inclusion and exclusion criteria are not used to reject people personally. Instead, the criteria are used to identify appropriate participants and keep them safe. The criteria help ensure that researchers will be able to answer the questions they plan to study.

If you plan to participate, some questions you might ask about the research include:

    * Why is this research being done and who is sponsoring it?       
    * How do the possible risks and benefits of the study compare with approved treatments for me?       
    * What are the possible immediate and long-term side effects?       
    * What other treatment options do I have?       
    * Will I have to pay anything to participate in the study?

Source: National Institutes of Health