What is a clinical trial?
A clinical trial is a research study involving human subjects to answer specific questions about vaccines or new therapies, or new ways of using known treatments. Clinical trials (also called medical research and research studies) are used to determine whether new drugs or treatments are both safe and effective. Carefully conducted clinical trials are the fastest and safest way to find treatments that work.
Ideas for clinical trials usually come from researchers. Pre-clinical trials typically study the actions of potential treatments in laboratory culture dishes or test tubes - called in vitro studies - or in laboratory animals such as mice, rats or monkeys. 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.
What is a protocol?
All clinical trials are based on a set of rules called a protocol. 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 are seen regularly by the research staff to monitor
their health and to determine the safety and effectiveness of their treatment.
^ Back to Top
What are clinical trial phases?
Clinical trials of experimental drugs proceed through four phases:
- In Phase I clinical trials, researchers test a new drug or treatment in
a small group of people (20 to 80) for the first time to evaluate its safety,
determine a safe dosage range and identify side effects.
- In Phase II clinical trials, the study drug or treatment is given to a
larger group of people (100 to 300) to see if it is effective and to further
evaluate its safety.
- In Phase III studies, the study drug or treatment is given to large groups
of people (1,000 to 3,000) to confirm its effectiveness, monitor side effects,
compare it to commonly used treatments and collect information that will
allow the drug or treatment to be used safely.
- Phase IV studies are done after the drug or treatment has been marketed.
These studies continue testing the study drug or treatment to collect information
about their effect in various populations and any side effects associated
with long-term use.
^ Back to Top
What protections are there for people who participate in clinical trials?
The government has strict guidelines and safeguards to protect people who choose
to 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. The "institution"
in IRB is usually a university or a hospital.
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. By federal regulation, all institutions
that conduct or support biomedical research involving people must have an IRB
that initially approves and periodically reviews the research.
^ Back to Top
What is 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. If
English is not your native language, you can ask for the consent documents in
languages other than English. 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.
It is also a good idea to take the consent documents home and discuss them
with family members or friends. Talking about your options can help you to feel
comfortable with your decision. If you decide to join the clinical trial, be
sure to ask for a copy of the informed consent documents so you can review them
at any time.
Remember, informed consent is more than signing a form. It is a process that
continues throughout 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.
People suffering from Alzheimer's disease may not be mentally capable of giving
consent, in which case the consent process must be conducted by next-of-kin
or a person granted power of attorney.
^ Back to Top
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.
The factors that allow you to participate in a clinical trial are called inclusion
criteria and the factors that keep you from participating are called exclusion
criteria. 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.
^ Back to Top
Who sponsors clinical trials?
Clinical trials are sponsored by government agencies: such as the National Institutes
of Health (NIH); pharmaceutical companies; individual physician- investigators;
health care institutions such as health maintenance organizations (HMOs); and
organizations that develop medical devices or equipment. Trials can take place
in a variety of locations, such as hospitals, universities, doctors' offices,
or community clinics.
^ Back to Top
What happens during a clinical trial?
The clinical trial process depends on the kind of trial you participate in. The
team will include doctors and nurses as well as social workers and other health
care professionals. They will check your health at the beginning of the trial,
give you specific instructions for participating in the trial, monitor you carefully
during the trial, and stay in touch with you after the study. It is important
to realize that in some cases, depending on the trial, there may be NO feedback
or NO individual feedback directly to the participant.
Some clinical trials involve more tests and doctor visits than you would normally
have for your illness or condition. For all types of trials, you will work with
a research team. Your participation will be most successful if you follow the
protocol carefully and stay in contact with the research staff. Some
terms that will help you understand what happens in a trial are defined
below.
^ Back to Top
What is a placebo?
A placebo (sometimes called a "sugar pill") is an inactive pill, liquid,
or powder that has no treatment value. In clinical trials, experimental treatments
are often compared with placebos to assess the treatment's effectiveness. In some
studies, the participants in the control group will receive a placebo instead
of an active drug or treatment.
^ Back to Top
What is a control 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.
^ Back to Top
What is a blinded or masked study?
A blinded or masked study is one in which participants do not know whether they are in the experimental or control group in a research study. Those in the experimental group get the medications or treatments being tested, while those in the control group get a standard treatment or no treatment.
^ Back to Top
What is a double-blind or double-masked study?
A double-blind or double-masked study is one in which neither the participants nor the study staff know which participants are receiving the experimental treatment and which ones are getting either a standard treatment or a placebo. These studies are performed so neither the patients' nor the doctors' expectations about the experimental drug can influence the outcome.
^ Back to Top
What are side effects and adverse reactions?
Side effects are any undesired actions or effects of drug or treatment. Negative
or adverse effects may include headache, nausea, hair loss, skin irritation or
other physical problems. Experimental treatments must be evaluated for both immediate
and long-term side effects.
In many Alzheimer's trials, the person with the disease is essentially a passive
bystander. The processing of information about the trial and decision-making
are the responsibility of the caregiver, spouse, next-of-kin or person designated
with power-of-attorney.
^ Back to Top
What are the benefits and risks associated with clinical trials?
There are both benefits and risks associated with clinical trials. By participating
in a clinical trial, you can:
- Take an active role in your own health care.
- Gain access to new treatments that are not available to the public.
- Obtain expert medical care at leading health care facilities during the
trial.
- Help others by contributing to medical research.
Clinical trials have risks:
- There may be side effects or adverse reactions to medications or treatments.
- The treatment may not be effective for you.
- The protocol may require a lot of your time for trips to the study
site, treatments, hospital stays, or complex dosage requirements.
^ Back to Top
What should I know before I join a clinical trial?
You should know as much as possible about the research study. It is important for you to feel very comfortable asking questions and the staff should answer them in a way you can understand. A list of sample questions appears below.
^ Back to Top
How should I prepare for the meeting with the research coordinator or doctor?
- Plan ahead and write down the questions you want to ask.
- Ask a friend or relative to come with you for support and to hear the responses
to your questions.
- Bring a tape recorder so you can replay the discussion after you get home.
^ Back to Top
What questions should I ask?
Some questions you might ask about the research include:
- Why is this research being done?
- What is the purpose of the study?
- Who is sponsoring the study?
- Who has reviewed and approved this study?
- Why does the research team think the treatment, drug or medical device
will work?
Some questions about your participation in the study include:
- Where is the study site?
- What kinds of therapies, procedures, and/or tests will I have during the
trial?
- Will they hurt? If so, for how long?
- How will the tests in the study compare to tests I would have outside the
study?
- How long will the study last?
- How often will I have to go to the study site?
- Who will provide my medical care after the study ends?
- Will I be able to take my regular medications during the trial?
- What medications, procedures or treatments must I avoid while in
the study?
- What are my responsibilities during the study?
- Will I have to be in the hospital during the study?
- Will the study researchers work with my doctor while I am in the
study?
- Can anyone find out that I am participating in a study?
- Can I talk to other people in the study?
- Will I be able to find out the results of the trial?
Questions about risks and benefits include:
- 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?
- Can my DNA test results be used to deny me insurance benefits or
employment?
Other questions include:
- What other treatment options do I have?
- Will I have to pay anything to participate in the study?
- What are the charges likely to be?
- Is my insurance likely to cover those expenses?
^ Back to Top
Should I continue working with my primary health care provider if I participate in a trial?
Yes. Most clinical trials provide short-term treatments related to a designated illness or condition, but not extended or complete primary health care. In addition, by having your health care provider work with the research team, you can ensure that your other medications or treatments will not conflict with the clinical trial protocol.
^ Back to Top
Can I leave a clinical trial after it has begun?
Yes. You can leave a clinical trial at any time. If you plan to stop participating, let the research team know why you are leaving the study.
^ Back to Top
Will I be paid for participating in a clinical trial?
Some clinical trials will pay you for joining the trial, while others will not. In some programs, researchers will reimburse you for expenses associated with participating in the research. Such expenses may include transportation costs, child care, meals and accommodations.
Courtesy of: National Institute for Allergy and Infectious Diseases
^ Back to Top
|