More than 25,000 cancer patients enroll in clinical trials each year through the National Cancer Institute. Many more patients are enrolled in clinical trials sponsored by other groups.
Clinical trials testing new treatments are carried out in phases.
Phase I — Is the Treatment Safe?
Doctors gather information about the side effects of the treatment and decide on the safe dose. Only a few patients in a few places take part in a Phase I trial.
Phase II — Does the Treatment Work?
In this step, doctors test the treatment to see how well it works. Most of the time, fewer than 100 patients are involved in Phase II trials.
Phase III — Is the Treatment Better?
Phase III trials compare the new treatment against the current standard therapy and randomly assign patients into one of the two groups. Many people from all over the country take part in these trials.
Phase IV — Are There Better Ways to Use the Treatment?
In this final step, treatments are tested to make sure they are safe and work well over a long period of time. This phase most often occurs once the new treatment has been approved for standard use. Anywhere from several hundred to several thousand people are enrolled in a Phase IV trial.
Each clinical trial calls for certain criteria that you must meet to be included in that trial, such as:
- Current health
- Medical history
- Stage of cancer
- Type of cancer
It's important to remember that clinical trials are completely voluntary. You can leave a trial at any time.
Before you enroll in a trial, you will need to know:
- What is the purpose of the study?
- What treatment will be given?
- What tests will be taken?
- What are the benefits and risk?
- Has the trial been approved by an Institutional Review Board?
Once you have the answers to these questions, you will be asked for informed consent. Informed consent is your written consent that you understand the answers to the above questions and agree to take part.
Join a Clinical Trial
If you are interested in joining a clinical trial, talk to your doctor. He or she can help you find out if a trial is right for you. Information on current trials can be found through the National Cancer Institute [Call 1-800-4-CANCER or visit to learn more.
Benefits to Participating?
- Access to promising new treatments that are not available outside of the clinical trial setting.
- The treatment being studied may be better than the standard approach.
- You are followed very closely by a research team made up of doctors and other health professionals.
- You may be the first to benefit from the new method.Results from the study may help others in the future.
Risks of Participating
- New drugs or treatments may not be any better than the standard care they are being compared to.
- New treatments may have side effects that are not expected.
- If you are in a randomized trial, you will not be able to choose if you are getting the new treatment or the standard approach.
- Health insurance may not cover all your costs.
- You may be required to make more frequent visits to the doctor.
Before joining a clinical trial, you may want to ask your doctor questions about the study and your treatment.
- What are you trying to learn from the study?
- What do doctors know already about the treatments being studied?
- What treatments and tests will I get during this trial?
- Who will be in charge of my care during the study?
- What are the differences between what I would get on this treatment and the standard treatment you would recommend?
- What are the benefits and risks?
- How will this affect my daily life?
- How long will the study last?
- What will I be asked to pay?
- How will I know if the study was successful?
Clinical trials fall into one of several categories, including:
These trials test new approaches that doctors believe may reduce your chance of developing cancer. Most involve healthy people who have not had cancer. Some studies are conducted with people who have had cancer in the past to try to find ways to prevent second cancers.
Since cancer is often easier to cure when it is found early, screening trials test methods to better detect cancer, especially in the early stages. These studies also help find out whether finding cancer before it causes symptoms will lessen a patient's chances of dying from the disease.
Diagnostic trials help answer whether or not there are new approaches that could be used to find certain types of cancer and at an earlier stage.
The purpose of these trials is to find out if a new treatment or technique is better than the standard treatment. This can include new approaches to radiation therapy, new drugs, vaccines, and different combinations of treatment.
Supportive Care/Quality of Life
These studies explore ways to improve the comfort and quality of life of people with cancer or survivors. These trials also study ways to better combat the side effects of some treatments.
These are generally done with another clinical trial and focus on how genetic makeup can affect detection, diagnosis, or response to cancer treatment.
Organizations or individuals looking for better treatments for cancer or new ways to prevent or detect cancer organize clinical trials. Each trial has a person in charge, usually a doctor, who is called the protocol chair or principal investigator.
Sponsors of clinical trials may include:
- Drug manufacturers
- Groups like the American Cancer Society
- Individual doctors at cancer centers or other medical institutions
- Technology companies National Cancer Institute
Most clinical trials are provided at no cost to you, however you will want to be sure of the details, including:
- Is the study completely covered by a sponsor, such as the government, drug manufacturer, or technology company?
- Will the sponsor pay for any special testing or extra doctor visits?
- Will the sponsor pay for any travel time or mileage expenses?
- If you have private insurance, it may pay for some or all of the costs of your treatment. Check with your provider.
- Medicare will pay for the routine costs for some government-sponsored clinical trials. Ask your doctor or call your local Medicare provider to find out what Medicare will pay for your treatment.