Cancer Clinical Trial Phases

Phases of cancer clinical trials

Treatments trials are a type of cancer clinical study that test new treatments, new combinations of treatments, and new combinations of drugs or new approaches to surgery or radiation therapy.

There are four phases of treatment studies including:

Phase I
Researchers test a new drug or treatment in a small group of patients (usually 20 to 80) for the first time to determine safety, the safe dosage range for the treatment and to identify any side effects.

Phase II
The studied drug or treatment is given to a larger group of patients (usually 100 to 300) to see if it is effective and to further determine its safety.

Phase III
The studied drug or treatment is given to large numbers of patients (usually 1,000 to 3,000 or more) to confirm its effectiveness, monitor side effects, compare it to commonly used treatments, and to collect data that will allow the treatment to be used safely.

Phase IV
After a drug or treatment is on the market, this phase is used to gather additional information about it, including risks, benefits and the best way to use it.

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