INFORMATION ON CLINICAL TRIALS FOR RESEARCH VOLUNTEERS
Clinical research trials are used to test and
evaluate investigational drugs and treatments.
Monitoring and ethical procedures
Everyone in a clinical trial is carefully monitored. Frequent
study-related medical exams and tests are performed to ensure
safety. Researchers follow strict ethical and scientific
principles to make sure that patients are protected and
valid results are produced.
A plan of how the study will be run, which is called a
protocol, is written to ensure that every researcher involved
in the study follows the same ethical and scientific principles.
The protocol is written by the study's sponsor. All researchers
taking part in the study will use the same protocol. It
describes how the study will be conducted in great detail
including the number of participants to be enrolled, the
amount of drug to be used and the types of medical tests
to be provided, etc.
To ensure patient safety, the protocol is reviewed and
approved by the organization that sponsors the study as
well as by an Institutional Review Board. In the review
of the protocol, the board seeks to ensure that participants
in the study will not be exposed to unreasonable or unethical
The process of evaluating new treatments does involve some
risk. Investigational drugs are first tested for safety
in Phase I trials. These studies use a small group of volunteers
to determine the best dose of the study drug. If the drug
is shown to be safe and well tolerated, it moves to Phase
II and III trials, where larger numbers of patients with
a specific disease receive the treatment. Side effects can
vary from patient to patient. It is important to remember
that clinical trials can result in unexpected, sometimes
dangerous, complications as well as potential therapeutic
benefits. However, the progress of patients in clinical
trials is carefully monitored.
Before the trial
Before enrolling anyone in a clinical trial, study site
staff will explain the possible risks and benefits to potential
study participants, as well as the procedures to be used
in the study and a participant's right to leave a study
at any time. These issues are summarized in a document called
an informed consent form. All clinical trial participants
are asked to read, understand, and sign the consent form
before beginning study treatment. It is important to ask
the study site staff to explain any part of the form that
Participants in a study must meet the eligibility criteria
(inclusion and exclusion criteria) that are outlined in
the protocol. These criteria, which differ from trial to
trial, include such characteristics as gender, age, health
problems, and previous or current treatments. These criteria
help exclude those who might be harmed by the study drugs
(such as pregnant women) or other treatments involved in
the research. These criteria also help to produce scientifically
reliable results by making sure that the study only enrols
certain types of patients. (For example, patients with certain
disease characteristics.) Thus researchers can determine
the benefits and disadvantages of the study drug more accurately.
For example, the study treatment may be effective for one
type of a disease but not another, or may be more effective
in women than men.
Leaving a trial
Trial participants may leave the trial at any time for
any reason. If you choose to leave the study, you will have
the chance to discuss other treatments with your own doctor
or a doctor from the study.
Not all clinical trials involve the use of a placebo (a
substance that looks like the study drug, but contains no
active drug). Some Phase III trials may compare investigational
therapies to the standard therapy used to treat the disease
of question. However, in some cases, there is no standard
treatment. When this is the case, the investigational treatment
may be compared to a placebo. When a placebo is used, study
participants are informed before they agree to take part
in the study that there is a chance that they will not receive
the study medication but may instead receive placebo
Most clinical trials have a "treatment group"
(which receives the study drug) and a "control group"
(which may receive standard treatment or placebo). In a
blinded or masked study, participants are not told which
group they are in. The reason for a blinded or masked study
is to avoid study bias. If people expect to do better on
a study drug, they may report hopeful signs to researchers
simply because they want to believe they are doing better.
Similarly, physicians may also be blinded to the treatment
a patient is receiving because, if they believe an experimental
treatment may work better, it may influence their report
of how the patient is doing. In either case, the study drug
may appear to work better than it really does. To prevent
this from happening, a study may be blinded or masked.
In trials where there is both a treatment and a control
group, participants are assigned to either group by chance.
This process is called "randomisation." Patients
are randomised to avoid study bias. Randomisation is used
to help ensure that study results are influenced only by
the treatment being tested.
Discussing your participation with your GP
You do not need a referral from your GP to participate
in a trial. It is up to you to decide if you wish to participate
or not. However, patients are usually encouraged to discuss
participation in the study with their own GP and their family.
You can continue to see your regular physician. Clinical
trials do not replace normal health care. In fact, trial
coordinators should provide regular updates about the study
to your regular physician.