What is a clinical trial?
Clinical trials are health-related research studies in people that are closely supervised and carefully follow a pre-defined protocol. Each study answers scientific questions and tries to find better ways to prevent, screen for, diagnose, or treat a disease. Clinical trials may be done to see how a new treatment compares with the standard treatment or to see if a new treatment is safe and effective for a certain condition or disease.
Why are clinical trials important?
Clinical trials are the only way that new treatments are developed for prevention, diagnosis, control, and treatment of diseases. Examples of discoveries that have been developed as a result of clinical trials are:
How do clinical trials work?
Drugs and/or devices are tested first in a laboratory and in animals. After safety and effectiveness is ensured in animals, a drug or device can be tested in people. For most trials, the study plan or protocol must be approved by the U.S. Food and Drug Administration (FDA). The FDA makes sure that people who agree to be in a trial are treated as safely as possible. All results must be reviewed by the FDA to determine if the drug or device is safe and effective for people. Each trial has a protocol that describes the condition or disease being studied, number of people to be included, what tests they will receive, and how the treatment plan will work. Doctors, nurses, and other health care providers may be part of your clinical trial treatment team. They will closely monitor your progress before, during, and after the trial. You may have more tests and doctor visits than you would have if you were not in the trial. You may have responsibilities, such as following the treatment plan, keeping a diary, filling out forms about your health, keeping your appointments, being on time, and taking your study drug exactly as prescribed.
Why should I participate in a clinical trial?
The health of millions of people has been improved because of advances in science and technology, and the willingness of thousands of individuals to take part in clinical research. Volunteers are the most valuable and most respected component of the clinical trial process. Volunteering for a clinical trial is a personal decision that should be discussed with your family. People volunteer for a number of different reasons including:
Who should not participate in a clinical trial?
If a participant has a strong desire to be in one treatment group over another, they should consider not participating in the study. A study participant should be willing to be assigned to any treatment group.
Who can participate in a clinical trial?
All clinical trials have rules about who can participate. Using inclusion/exclusion criteria is an important principle of medical research that helps to produce reliable results. The factors that allow someone to participate in a clinical trial are called "inclusion criteria" and those that prevent someone from participating are called "exclusion criteria.” These criteria are based on such factors as age, gender, the type and stage of a disease, previous treatment history, and other medical conditions. Some research studies seek participants with illnesses or conditions to be studied in the clinical trial, while others need healthy participants. 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. Enrolling participants with similar characteristics helps to ensure that the results of the trial will be due to what is under study and not other factors. In this way, the criteria help researchers achieve accurate and meaningful results.
What is informed consent?
Informed consent is the process of learning the key facts about a clinical trial before deciding whether or not to participate. It is also a continuing process throughout the study to provide information for participants. To help someone decide whether or not to participate, the doctors and nurses involved in the trial explain the details of the study. Then the research team provides an informed consent document that includes details about the study, such as its purpose, duration, required procedures, and key contacts. Risks and potential benefits are explained in the informed consent document. The participant then decides whether or not to sign the document. Informed consent is not a contract, and the participant may withdraw from the trial at any time.
What are the benefits and risks of participating in a trial?
The benefits of participating in a clinical trial include:
Risks are involved in clinical trials. The specific risks associated with any research protocol are described in detail in the consent document, which you are asked to sign before taking part in research. Possible risks of participating in a clinical trial include:
How is the safety of the participant protected?
The ethical and legal codes that govern medical practice also apply to clinical trials. In addition, most clinical research is federally regulated with built in safeguards to protect the participants. The trial follows a carefully controlled protocol, a study plan which details what researchers will do in the study. As a clinical trial progresses, researchers report the results of the trial at scientific meetings, to medical journals, and to various government agencies. Individual participants' names will remain secret and will not be mentioned in these reports.
An addition, an Institutional Review Board (IRB) committee assures appropriate steps are taken to protect the rights and welfare of people participating in approved research studies. An IRB:
What should I consider before participating in a trial?
People should know as much as possible about the clinical trial and feel comfortable asking the members of the health care team questions about it, the care expected while in a trial, and the cost of the trial. The following questions might be helpful for the participant to discuss with the health care team. Some of the answers to these questions are found in the informed consent document.
Can I change my mind after the trial has begun?
Yes. Research is voluntary and a participant can leave a clinical trial, at any time without compromising their care. When withdrawing from the trial, the participant should let the research team know about it, and the reasons for leaving the study.
What is a protocol?
A protocol is a study plan on which all clinical trials are based. The plan is carefully designed to safeguard the health of the participants as well as answer specific research questions. A protocol describes what types of people may participate in the trial; the schedule of tests, procedures, medications, and dosages; and the length of the study. While in a clinical trial, participants following a protocol are seen regularly by the research staff to monitor their health and to determine the safety and effectiveness of their treatment.
What are the phases of clinical trials?
Clinical trials are conducted in phases. The trials at each phase have a different purpose and help scientists answer different questions.
Phase I Trials are initial studies to test a new drug or treatment in people for the first time. Because of this, these studies may have a higher risk level to you as a volunteer. Phase I trials usually enroll less than 100 healthy volunteers in each trial and provide information on the safety, dose range and side effects.
Phase II Trials test the safety and effectiveness of the treatment in up to several hundred people with the disease or condition being studied.
Phase III Trials test the treatment in several thousand people to define effectiveness, side effects, safety and comparison to other treatments. After Phase III trials are complete, the sponsor may request FDA approval to license the drug or device as a treatment for the disease or condition under study.
Phase IV Trials are conducted after the treatment has received FDA approval. These trials involve even larger numbers of people to further identify the drug’s risks, benefits and optimal use. In addition, a phase IV trial can be used to investigate a new clinical indication for a previously approved treatment.
What is a placebo?
Placebos are harmless, inactive substances with no treatment value made to look like the real medicine used in a clinical trial. In clinical trials, experimental treatments are often compared with placebos to assess the experimental treatment's effectiveness. In some studies, the participants in the control group will receive a placebo instead of an active drug or experimental treatment.
What is a placebo or control group?
A control is the standard by which experimental observations are evaluated. In many clinical trials, one group of patients will be given an experimental drug or treatment, while the control group is given either a standard treatment for the illness or a placebo.
What is the placebo effect?
Medical research is dogged by the placebo effect - a physical or emotional change, occurring after a substance is taken or administered, that is not the result of any special property of the substance. The change may be beneficial, reflecting the expectations of the participant and, often, the expectations of the person giving the substance. The placebo effect is very powerful. For example, a large red pill has a stronger placebo effect than a small white pill, and injections have a stronger placebo effect than pills. Presently, medical techniques use three ways to rid clinical trials of the placebo effect. These methods have helped discredit some previously accepted treatments and validate new ones. Methods used are the following: randomization, single-blind or double-blind studies, and the use of a placebo.
People with serious illnesses often question why scientists include a placebo when their illness is such a threat. Currently, the treatments being tested are hoped to slow down the progression of the disease. Science is looking for small changes in the course of the illness. Even in ALS, the placebo effect can occur and without a control group, we might not be able to tell if an agent is really working. In the future, when we find a treatment that will reverse the condition, a placebo group may not be needed.
What is randomization?
Randomization is when two or more alternative treatments are selected by chance, not by choice. The treatment chosen is given with the highest level of professional care and expertise, and the results of each treatment are compared. Analyses are done at intervals during a trial, which may last years. As soon as one treatment is found to be definitely superior, the trial is stopped. In this way, the fewest number of patients receive the less beneficial treatment.
What are single-blind and double-blind studies?
In single- or double-blind studies, the participants don't know which medicine is being used, and they can describe what happens without bias. Blind studies are designed to prevent anyone (doctors, nurses, or patients) from influencing the results. This allows scientifically accurate conclusions. In single-blind ("single-masked") studies, only the patient is not told what is being given. In a double-blind study, only the pharmacist knows; the doctors, nurses, patients, and other health care staff are not informed. If medically necessary, however, it is always possible to find out what the patient is taking.