What is meant by a clinical trial?
Clinical trials are a method designed to scientifically determine the effectiveness of various treatment regimens. Clinical trials for brain tumors most often evaluate chemotherapy, radiation therapy, or biologic therapy. These studies consist of four phases used in the evaluation of investigational drugs that may have therapeutic indications for patients.
What are the "phases"?
When determining whether you want to participate in a clinical trial,
it is important to understand what is meant by the "phase" of the study.
Researchers group treatments into "phases" based on the known
information about the treatment and what information they are seeking.
The search for brain tumor therapy begins with treatments first being
evaluated in research laboratories and on animals. This initial research
lays a groundwork, but can’t predict exactly how a treatment will work with
brain tumor patients.
The "phases" group treatments into what question the researcher is trying to answer. The following describes the
primary goal of the various phases of clinical trials.
Phase I:Who conducts clinical trials?
Determination of safe drug doses and/or schedules of a new drug when given to people. The treatment has not been evaluated in people with brain tumors before. The main goal is to determine what is the safe dose of medication and what side effects the person experiences. The treatment is considered promising for treating brain tumors, but evaluating response is not the primary goal of the study. Patients get a specific dose of drug(s) and are carefully observed for side effects.
Phase II:
Determination of therapeutic efficacy. The safe dose of medication has already been determined, and the researcher wants to determine whether the treatment shrinks the tumor and extends the person’s survival.
Phase III:
Comparison of the drug to an existing, effective standard therapy. In this "phase," the person can receive either the experimental treatment or the standard treatment. A computer randomly assigns the person to a treatment. This process is called randomization. The researcher does not know which treatment is best, therefore preventing bias in determining which treatment the person will receive. In this way, the treatment can be compared directly to a standard treatment to determine which is a better approach to therapy.
Clinical trials are conducted by various institutions and groups. Each clinical trial follows a treatment plan or "protocol." These protocols are defined by the researchers initiating the clinical trial, and undergo close scrutiny at each institution or hospital by an Institutional Review Board (IRB). The IRB reviews a clinical trial to be sure it is designed with safeguards to protect people who participate and to prevent significant risks. The following lists the various groups that may initiate a clinical trial.
How do I choose a clinical trial?
- Institutions:Individual institutions or hospitals conduct studies of various drugs. The individual or group of researchers at that institution may first try a treatment in the research laboratory and then proceed to testing with people with brain tumors. Institutional trials may be Phase I, II, or III.
- NCI Sponsored CNS Consortia: These are groups of specialized brain tumor centers from around the United States that receive funding to test innovative new treatments for brain tumors. There are currently two consortia that are made up of multiple medical centers; one consortia is based at Johns Hopkins University Hospital and the other is based at the University of California at San Francisco Medical Center. These groups test new treatments in Phase I and II testing.
- National Cooperative Groups: These groups consist of both university and community hospitals throughout the United States. The goal is to test new treatments for both efficacy and the ability to be done in a community setting. These groups include The Eastern Cooperative Oncology Group (ECOG); The Southwestern Oncology Group (SWOG); The Radiation Therapy Oncology Group (RTOG); and the North Central Cancer Treatment Group (NCCTG). Pediatric Groups include the Pediatric Oncology Group (POG) and the Children’s Cancer Group (CCG). These groups test treatments in Phase II and III testing.
- Pharmaceutical Sponsored Multi-Institutional Trials: Individual pharmaceutical companies often form consortia of hospitals to investigate a drug which they have developed. These trials can be Phase I, II, or III depending on the level of knowledge of that drug for brain tumors.
People chose to take part in clinical trials for various reasons, whether to try an innovative treatment, hope for a cure, to attempt to
feel better, or to assist in helping others in the future. If you are thinking about participating in a
clinical trial, there are multiple trials to choose.
Which trial is best for you is dependent on several factors, including:
Which is the best clinical trial available?
Being diagnosed with a brain tumor often thrusts you and your family into
an unfamiliar world. There has been an explosion of new treatments for brain tumors, and it is difficult to find the information quickly and choose the treatment which is right for you. As new clinical trials are opening
frequently, it is impossible to be sure which is the "best"
treatment available.
There have been recent trends in brain tumor treatment which
focus on a whole new approach to treatment. While it is impossible to say which
treatment is the best, the following lists the most current trends in brain tumor
treatment. Some of these treatments are very new, and only in Phase I testing.
While promising, the actual effect they will have on tumors is unknown.
Antiangiogenesis This approach allows the researcher to focus on certain characteristics which allow tumors to grow. This group of agents work by preventing new blood vessel formation, thereby preventing tumor growth. Most agents are currently in Phase I testing, and toxicities (side effects) as well as effect on tumor growth are not yet known.What is it like to take part in a clinical trial?
Gene Therapy: Current clinical trials utilizing gene therapy are aimed at modifying tumor behavior. For example, trials are being organized that inject genes directly into the tumor bed. The gene is designed to stimulate programmed cell death. These studies are in early Phase I testing and results are not known.
Differentiation Agents: This treatment (e.g. retinoids) affect the tumor by causing tumor cells to behave more like the nonmalignant form of the cell. Hopefully, this will slow the rate of growth of the tumor. These agents are undergoing early Phase I and Phase II trials.
Novel Routes of Chemotherapy: Several different methods of delivering chemotherapy (i.e. by disrupting the blood brain barrier, by continuous infusion, or direct instillation of chemotherapy into the tumor) are currently being tested with brain tumors. These trials are in Phase I, II, and III testing.
If you participate, the first step is called informed consent.
Informed consent means that if you elect to participate in the trial,
you fully understand the risks and benefits of the treatment and freely elect
to take part. You will then be asked to sign a consent form. This does not
mean that you cannot leave the trial, but only that you understand the
protocol.
You may elect to leave a clinical trial at any point in the process.
During the course of the clinical trial, you will be evaluated closely and required
to report symptoms that you experience. This may require extra physical
examinations, tests, or filling out forms. The informed consent form will
outline this for you.