Clinical trials are a necessary part of the drug development process. They help to assure that a drug is safe and does what it is supposed to effectively. Before the clinical trial phases begin, a drug is first tested in a laboratory with human cells and animals. If these preliminary tests look promising the drug can then be researched using human subjects. There are four phases of human clinical trial phases:
- Phase I – determine a drug’s safety, can last several months and usually include 20 to 100 healthy volunteers
- Phase II – test the efficacy of a drug, can last several months to 2 years and include several hundred patients who may receive the experimental drug or a placebo
- Phase III – further test a drug’s efficacy, many involve randomized and blind testing in several hundred to thousands of patients and can last several years
- Phase IV – compare the test drug with others on the market, monitor long-term effectiveness, and determine a drug’s cost-effectiveness
Every clinical trial has its benefits and risks. Although attempts are made to control the risks in clinical trials, many are unavoidable. It is up to patients and their care providers to decide if participating in a clinical trial would be beneficial.
You can learn more about clinical trials from the following sources:
