FAQ - Frequently Asked Questions
What is a clinical
trial?
A clinical trial refers to any experiment in which one or
more human subjects receive a drug or device for the purpose
of determining the safety and/or efficacy of a diagnostic, therapeutic,
or preventive use in human subjects.
What
are the phases of a clinical trial?
Phase I - Phase I trials include the initial introduction
on an investigational new drug into humans. These studies are
typically conducted with healthy volunteers, sometimes where
the drug is intended for use in patients with a particular disease,
however such patients may participate as subjects. Phase I trials
are designed to determine the metabolic and pharmacological actions
of the drug in humans, the side-effects associated with increasing
doses, (to establish a safe dose range) and if possible, to gain
early evidence of effectiveness; they are typically closely monitored.
The ultimate goal of Phase I trials is to obtain sufficient information
about the drug's pharmokinetics and pharmacological effects to
permit the design of well-controlled, sufficiently valid Phase
II studies. Other examples of Phase I studies include studies
of drug metabolism, structure-activity relationships, and mechanisms
of actions in humans, as well as studies in which investigational
drugs are used as research tools to explore biological phenomena
or disease processes. The total number of subjects involved in
Phase I investigations is generally in the range of 20-80.
Phase II - Phase II trials include
controlled clinical studies conducted to evaluate the drug's
effectiveness for a particular indication in patients with the
disease or condition under study, and to determine the common
short-term side effects and risks associated with the drug. These
studies are typically well-controlled, closely monitored, and
conducted with a relatively small number of patients, usually
involving no more than several hundred subjects.
Phase III - Phase III trials involve
the administration of a new drug to a larger number of patients
in different clinical settings to determine the safety, effectiveness,
and appropriate dosage. They are performed after preliminary
evidence of effectiveness has been obtained and are intended
to gather necessary additional information about effectiveness
and safety for evaluating the overall benefit-risk relationship
of the drug, and to provide an adequate basis for physician labeling.
In Phase III studies, the drug is used the way it would be administered
when marketed. When these studies are completed and the sponsor
believes that the drug is safe and effective under specific conditions,
the sponsor applies to FDA for approval to market the drug. Phase
III trials usually involve several hundred to several thousand
patients.
Phase IV - Concurrent with marketing
approval, FDA may seek agreement from the sponsor to conduct
certain postmarketing (Phase IV) studies to delineate additional
information about the drug's risks, benefits and optimal use.
These studies could include, but would not be limited to, studying
different dosages or schedules or administration than were used
in Phase II studies, use of the drug in other patient populations
or other stages of the disease, or use of the drug over a longer
period of time.
What
is an Investigational New Drug?
A drug or device permitted by FDA to be tested in humans, but not yet determined
to be safe and effective for a particular use in the general population, and
not yet licensed for marketing.1
Who
is the Principal Investigator and how is that person different
from an Investigator?
The Principal Investigators is the individual with primary responsibility for
the conduct of a research project. In a clinical trial, the Investigator is
an individual who actually conducts an investigation. Any interventions (e.g.
drugs) involved in the study are administered to subjects under the immediate
direction of the Investigator. A Principal Investigator and an Investigator
may be the same individual.*
You should be able to answer the following questions once you
have met and discussed a clinical trial with the physician:
- What is the purpose of the study?
- What is required of me?
- Will I receive treatment when participating
in a study?
- What are the direct benefits to me?
- Will my participation benefit others?
- Will my privacy be protected?
- Will anyone know I am participating in a study?
- Are there risks? If so, what?
- Who is sponsoring the study?
- Will I have to pay for anything? If so, what?
- What if I am hurt as a result of the study?
- Will I be paid for participating?
- Who can I call if I have questions?
*The OPRR 1993 Protecting Human Research
Subjects Institutional Review Board Guidelines, pp5-6, 5-7
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