Clinical Trial Basics
Clinical Trials
are in-depth medical research studies conducted to understand
whether promising approaches to
cancer
prevention, diagnosis and treatment
are safe and effective.
Cancer research, in general, includes four types of trials:
- Treatment: research to test new approaches
to treatment including new drugs, drug combinations, radiation and
surgery
- Prevention: research to investigate
methods to prevent the disease from occurring in people who have previously
not had cancer; or prevent the cancer from recurring in patients who
previously have been diagnosed with the disease
- Screening: research to find the optimum
approach in detecting cancer before symptoms occur; includes
imaging
,
laboratory and
genetic testing
- Quality of Life: research to investigate
means of improving cancer patients' and survivors' quality of life;
areas explored include the management of fatigue, nausea, pain, weight
loss and depression associated with cancer treatments
Clinical trials progress through a series of stages meant to ensure
safety of patient and effectiveness of treatment:
- Phase I: a drug or treatment is initially
evaluated with a limited group (approximately 20-30) to determine its
safety, optimal dose or treatment levels and identify side effects
- Phase II: the
experiemental
study's
drug or treatment is tested for safety and effectiveness and usually
involves a larger number of participants (approximately 100-300) compared
to Phase I
- Phase III: the experimental study's
drug or treatment is given (administered) to confirm findings of Phase
II and to compare it to existing treatments. A greater amount of information
is collected in order to determine the safety of the drug or treatment
(typically involves 1,000-3,000 participants)
- Phase IV: after the drug or treatment
gains FDA approval, the study enters the marketing stage. This study
observes the drug or treatment over a lengthy time period and involves
a significantly larger number of participants (thousands). The purpose
is to evaluate side effects, risks and benefits of a drug; and is typically
conducted by the drug maker