Clinical trials, also called clinical studies, test new methods to treat, diagnose and prevent cancer. Only treatments that provide promising results in laboratory tests advance to clinical trials.
Phase I trials are the first step at testing new treatments in people. They help researchers determine the best way to administer a new treatment and the appropriate dosage. These trials also establish whether a treatment has any potentially harmful side effects. Phase 1 trials involve a small number of people.
Phase II trials focus on learning whether a new treatment can shrink a tumor, improve blood test results or provide other desirable effects. There are usually involving fewer than 100 participants.
Phase III trials compare the new treatment to the best existing treatment for a particular type of cancer. Many patients — from the hundreds to even the thousands — receive either the new treatment or the best existing treatment. A Phase III trial may involve adding a new drug to an already-proven combination of drugs to see if the new combination is more effective.
For a more complete description of how clinical trials are structured, see our paper Participating in a Prostate Cancer Clinical Trial.
To Learn More About Clinical Trials
The National Cancer Institute provides a Clinical Studies Support Center in Bethesda, Maryland. You can talk with an Information Specialist by calling 1-888-NCI-1937 between 9:00am and 5:00pm Eastern Time, Monday – Friday. You may also contact the PCRI Helpline.
To Locate Clinical Trials
EmergingMed.com is a free and confidential cancer clinical trial matching and referral service.
- See if you match the enrollment criteria of the clinical trials in this database.
- Customer Service Specialists will link you at your request to the doctors and nurses conducting the clinical trials you match
Clinical Trials Help (Coalition of Cancer Cooperative Groups) – Access TrialCheck® to find trials that may be right for you.
Many cancer centers, especially members of National Comprehensive Cancer Network (NCCN), operate trials that are not listed on the databases above. To learn about these trials, access the individual centers via the NCCN Member Page or by calling a cancer center in your area.
To Search for Published Studies