What Are Clinical Trials?
A clinical trial is a drug study sponsored by a pharmaceutical
or biotechnology company. There are cases, however, where health-related
government agencies provide funding and other resources for
a clinical trial. The purpose of these studies is to find out
whether a medication is safe to use and effective against various
diseases or medical conditions. In order to study the medication,
several questions need to be answered first. For example, what
patient population or disease is the drug meant to treat? What
criteria should be used for accepting participants into the
study? What general and disease-specific information are the
study doctors going to obtain? Essentially, once these and other
important study questions are answered, the study doctors (investigators)
are chosen, the regulatory documents are approved, and the study
is ready to begin.
Why are clinical trials important?
There are a several reasons why clinical trials are important.
First, the participant may have a positive response to the study
medication, and their disease or condition may improve. In addition,
participants receive free laboratory and medical testing. More
often than not, the study medication is in development because
it works differently than other drugs on the market, and therefore,
it may present an alternative course of treatment for the patient.
Second, participation in a clinical trial helps manufacturers
make informed decisions about whether to pursue getting a particular
drug approved by the Food & Drug Administration (FDA). Finally,
data from one patient (who completes the entire study) can be
an important part of a drug development program. In the best
case scenarios, these data can help get an exciting new drug
approved by the FDA, and ultimately, continue the industry's
efforts in developing medications that are safer, more effective,
and work faster than any before them.
How are a participant's rights and safety protected?
The FDA is the governing agency that develops the policies
and guidelines for all medical research, regardless of manufacturer,
study phase, or drug type. There are also independent Institutional
Review Boards (IRB) that review and approve all study-related
documents, such as protocols, Informed Consent forms, physician
credentials and eligibility, and patient recruitment materials,
such as print advertisements and public service announcements.
What are the phases of the clinical trial process?
There are three primary phases an investigational drug has
to go through before it can be approved by the FDA, and a fourth
phase that an approved drug may enter.
Phase I
In this phase of a clinical trial, the manufacturer wants to
find out how the drug works in healthy study participants. Mode
of action (how the drug exerts its effects), safety, and side
effects -- these are some of the main issues that are of the
utmost concern to drug makers at this stage of the clinical
trial process. It is important to note that in Phase I studies,
the overall safety of the medication in patients has not been
established.
Phase II
A drug reaches Phase II only when the FDA has reviewed the
Phase I data and concludes that the drug is safe for patients,
and that its clinical activity may be beneficial against a particular
disease or condition. At this point, a larger group of patients
are enrolled and condition- or disease-specific rating scales
are used to record data.
Phase III
This is an important turning point for drug manufacturers.
The medication has already past the rigorous testing and review
process required by the FDA, and now it's ready to be studied
in an even larger patient population, with even more advanced
rating scales and clinical measures. In recent years, there
has been a growing industry trend to not only measure clinical
effectiveness at this phase, but also measure "real world"
results. For example, if a patient shows clinical improvement
after entering the study, how are their activities of daily
living improving (e.g., the patient can work in the garden more
often or attend their child's games on a regular basis)? Most
medications that reach Phase III will at least be considered
for approval by an FDA advisory board.
Phase IV
At this phase in development, the drug has already been granted
FDA approval. Phase IV studies are often performed to either
identify an additional use for an already approved drug, or
to gather additional safety information from a larger group
of patients. In some cases, Phase IV studies are implemented
to establish effectiveness in a subgroup of patients, for example,
patients over age 65.
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