What is a Clinical Trial?

What Is a Clinical Trial?

In cancer research, a clinical trial is a study conducted with cancer patients, usually to evaluate a new treatment. Each study is designed to answer scientific questions and to find new and better ways to help cancer patients. The search for good cancer treatments begins with basic research in laboratory and animal studies.

The best results of that research are tried in patient studies, hopefully leading to findings that may help many people. Before a new treatment is tried with patients, it is carefully studied in the laboratory. This research points out the new methods most likely to succeed, and, as much as possible, shows how to use them safely and effectively.

But this early research cannot predict exactly how a new treatment will work with patients. With any new treatment there may be risks as well as possible benefits. There may also be some risks that are not yet known.

Clinical trials help us find out if a promising new treatment is safe and effective for patients. During a trial, more and more information is gained about a new treatment, its risks, and how well it may or may not work. Standard treatments, the ones now being used, are often the base for building new, hopefully better treatments.

Many new treatments are designed on the basis of what has worked in the past, in efforts to improve on this. Only patients who wish to, take part in a clinical trial. You may be interested in or asked to enter a trial. Learn as much as you can about the trial, before you make up your mind.

Why Are Clinical Trials Important?

Advances in medicine and science are the results of new ideas and approaches developed through research. New cancer treatments must prove to be safe and effective in scientific studies with a certain number of patients before they can be made widely available.

Through clinical trials, researchers learn which approaches are more effective than others. This is the best way to test a new treatment. A number of standard treatments were first shown to be effective in clinical trials. These trials helped to find new and better treatments.

Why Would a Patient Be Interested in a Clinical Trial?

Patients take part in clinical trials for many reasons. Usually, they hope for benefits for themselves. They may hope for a cure of disease, a longer time to live, a way to feel better. Often they want to contribute to a research effort that may help others.

Based on what researchers learn from laboratory studies, and sometimes earlier clinical studies and standard treatments as well, they design a trial to see if a new treatment will improve on current treatments. The hope is that it will. Often researchers use standard treatments as the building blocks to try to design better treatments.

Although there is always a chance that a new treatment will be disappointing, the researchers involved in a study have reason to believe that it will be as good as, or better than, current treatments. The patients in a clinical trial are among the first to receive new research treatments before they are widely available. How a treatment will work for a patient in a trial can't be known ahead of time.

Even standard treatments, although effective in many patients, do not carry sure benefits for everyone. But patients should choose if they want to take part in a study or not, only after they understand both the possible risks and benefits. The patients who take part in clinical trial procedures that do prove to be better treatments have the first chance to benefit from them.

All patients in clinical trials are carefully monitored during a trial and followed up afterwards. They become part of a network of clinical trials carried out around the country. In this network, doctors and researchers pool their ideas and experience to design and monitor clinical studies. They share their knowledge from many specialties about cancer treatment and care.

Patients in these studies receive the benefit of their expertise. At cancer centers, patients receive care from a special research team. Through new programs, community hospitals and doctors are also coming more and more into the research network.

Are There Risks or Side Effects in Clinical Trials?

Yes. The treatments used in clinical trials can cause side effects and other health risks depending on the type of treatment and the patient's condition. Side effects vary from patient to patient. Because clinical trials are research into new areas of treatment, the risks involved are not always known ahead of time, though efforts have been made to find out what they might be.

For this reason, trials can carry unknown dangers and side effects as well as hoped-for benefits. Patients need to know what is involved in a study-what side effects may be expected- and, as much as possible, what unknowns or uncertainties they may be facing. Your doctor or nurse will tell you about the treatments being tested and will give you a form to read that discusses the risks and hoped-for benefits.

If you agree to take part, you will be asked to sign a form, called the informed consent form. Before you sign, be sure you understand what risks you face. Ask the doctor or nurse to explain any parts of the form or the trial that are not clear. If you do not want to be in the trial, you may refuse. Even if you sign the form, you are free to leave the trial at any time and can receive other available medical care.

In clinical trials, most side effects are temporary and will gradually go away once treatment is stopped. For example, some anti-cancer drugs cause hair loss and nausea and some do not. They can also affect the bone marrow which produces blood cells. During treatment, the number of blood cells, called blood counts, may fall too low. Since this could lead to possible infection or other problems, patients have their blood counts checked often.

Luckily, bone marrow has a great ability to replace blood cells, so that blood counts can usually return to normal. Some side effects in clinical trials can be permanent and serious, even life-threatening. Also, certain side effects may not appear until later, after the treatment itself is over. (These "late" effects may include damage to a major organ like the heart, lungs, or kidneys; sterility; or a second cancer.)

Many cancer patients are now living longer, largely because of better treatments. Researchers are concerned and trying to prevent late complications of treatments. As a patient, it can be hard to decide about your treatment. There are a number of things to consider. Cancer is a life-threatening disease which causes symptoms of its own that are not related to treatment.

In each case, the unavoidable risks of the cancer itself, and your condition, should be weighed against the potential risks and benefits of a new research treatment. Standard treatments, as well as treatments in clinical trials, can also cause side effects and risks.

Why Does Cancer Treatment Have Side Effects?

Any medical treatment can carry the potential for side effects in some patients. Cancer treatment is particularly powerful, because it is designed to destroy constantly dividing cancer cells. It can also affect healthy dividing cells and this can cause side effects. The challenge to researchers has been to develop treatments that destroy cancer cells but do not harm healthy cells.

What Is Being Done To Lessen Side Effects of Treatment? Cancer researchers are trying to make cancer treatment more effective and lessen its side effects for the cancer patient. Results of such efforts include: new anticancer drugs with less side effects; better antinausea medicine; some shorter periods of time on anticancer drugs; special ways to protect normal tissues during radiation therapy; new methods of surgery that are less extensive and less damaging to the body; and psychological support programs and information on ways to cope during difficult times. How patients feel during and after treatment is important.

Source: National Institutes of Health and National Cancer Institute No implicit or explicit endorsement of any company is implied.