Types of Clinical Trials
Clinical trials are generally conducted in steps, called Phase I, II, or III.
Phase I: Trials learn whether a drug or device is safe or not.
In these dose-finding or dose-escalation trials, patients receive very low doses of the drug being studied. The dose is gradually increased in several small groups of patients until patients begin to have side effects. Once the maximum tolerated dose (MTD) of the drug is identified, the study is finished. The dose found in the phase I study is then used in the next phase II trial. Patients are offered participation in Phase I trials only if they have already received standard treatments that are known to be effective for their particular cancer.
Phase II: Trials find out whether a new treatment works against the cancer that is being studied.
Generally, phase II trials study drugs that have not yet been approved by the FDA (investigational drug) or are approved for use in a different type of cancer.
Phase III: Trials compare new treatments to the current “standard” treatment to see if it gives a better result for patients.
Patients are randomly assigned to one of the treatments being studied. Often in phase III trials, the doctor and the patient do not know which treatment the patient is receiving (‘blinded’ study) and the treatment plan may include a placebo ("dummy" drug that has no effect). The purpose of randomization, blinding and placebo is to remove any bias from the trial so that comparisons can be made fairly.
Possible benefits of participating in a clinical trial include:
- Access to promising new drugs or approaches that may not be available outside the clinical trial.
- Better treatment results compared to "standard" treatment.
- Results from the study may help others in the future.
- Thorough medical attention from the doctor and the research team.
Possible risks of participating in a clinical trial include:
- New drugs under study may not be better than the standard care.
- New treatments may have side effects or risks that doctors do not expect.
- In randomized trials, patients are not able to choose the therapy that they receive.
- More visits to the doctor or tests may be required in a clinical trial.
Another useful website for learning about Clinical Trials is EmergingMed.
Last Updated on 11/15/2012 12:54:58 PM