About Breast Cancer>Treatments > Clinical trials

Clinical trials


Clinical trials are research studies carried out in people. They evaluate new therapies and compare the new treatments to current ones.

Thanks to clinical trials, breast cancer treatment no longer uses a one-size-fits-all approach. In many cases, we can now use more specific therapies based on the type of cancer. All these therapies were proved effective in clinical trials.


Clinical trials provide treatment

Breast cancer clinical trials are designed to find out the effects of

  • a new medicine, surgery or radiation treatment
  • a new combination of existing medicines or therapies
  • the order in which medicines are given, called treatment sequence
  • different amounts of medicine given, called its dosing schedule
  • the way that the dose is given, such as by mouth or injected into a vein

Other clinical trials look at ways to

  • screen for breast cancer
  • manage symptoms
  • keep the cancer from coming back
  • find genetic links to cancer
  • evaluate complementary and integrative therapies
  • improve quality of life

Getting breast cancer treatment through a clinical trial may give you access to a new medicine or approach, or to the best standard therapy in use today.

If a standard treatment exists, you would not receive just a placebo, an inactive pill. In large clinical trials where there are standard treatments, you would get either:

  • the standard treatment alone
  • the standard treatment plus the treatment under study
  • the standard treatment plus a placebo

Sometimes in smaller clinical trials, you may just receive the treatment under study. The goal is to see whether the study treatment is effective or, in some cases, just to see whether it’s safe.

As you talk with your doctors, ask about the clinical trial goals and why your doctors feel you’re a good candidate for it.


Taking part in clinical trials

Breast cancer clinical trials are for women or men with early-stage or metastatic disease of all subtypes. Studies are essential to improve treatment for people with all breast cancer stages.

Clinical trials are a treatment option to consider when you are first diagnosed. Many trials are only open to people who haven’t had any treatment yet. Other studies are designed for people who had cancer treatment in the past, or are living with metastatic breast cancer and have had many different treatments.

Taking part in a clinical trial is often similar to receiving treatment outside a trial. You will have a medical team, with a doctor-researcher responsible for your care. You’ll also be assigned a clinical trial coordinator to answer your questions and address your concerns. In some cases, your trial medicine can be given at your own treatment center, so you can continue to see the care team you already have.


What are the benefits and risks of clinical trials?

If you’re interested in joining a clinical trial, consider your options and what’s important to you. A clinical trial may help you get a new treatment, but it could impact your life in other ways, too.

Participating in a clinical trial is voluntary, but not everyone can join every trial. If you are eligible for a specific study, talk about the pros and cons with the study team, your care team and people close to you. Consider these benefits and risks:

Benefits of Clinical Trials

  • You may receive new medicines, combinations of medicines or try treatment methods that are not available outside of the clinical trial. These may be more effective or have fewer side effects than the current standard treatment.
  • If a new treatment works, you may benefit from it before it is available to the public.
  • You will always receive at least the current standard treatment recommended for you.
  • Doctors and nurses on the study team will closely monitor your treatment, often more closely than in standard breast cancer care. An independent safety committee charged with keeping the trial participants safe from harm also watches over your care.
  • The costs of some trials and trial medicines are covered by insurance or other programs, or are free to participants.

You may feel good knowing your participation could help others affected by breast cancer in the future.

Risks or concerns of clinical trials

  • The new treatment being tested might not be more effective than the standard therapy.
    • Remember, in a randomized trial you will always get at least the standard of care.
    • If you are in a trial where you could receive the standard treatment plus the treatment under study, even if the new treatment isn’t effective, you may still benefit from the standard treatment you are taking.
  • You may have side effects that are worse than those caused by the standard treatment or that researchers did not know about.
  • In a randomized trial, you won’t be able to choose your treatment.
    • Remember that although you might not get the new therapy, you will still get the standard treatment appropriate for your care.
  • You may have to pay costs for medicines, tests and doctor visits related to the trial that your health insurance might not cover.
    • Ask the study team and your insurer what will be covered.
    • Check your informed consent document to see what costs you could have.
  • You may need to take extra time away from work or your personal life, or have more travel or childcare costs, because of the study.
    • In some cases, the study may help with expenses.
    • If you meet certain criteria, the federal Family and Medical Leave Act of 1993 protects you and your caregiver from losing your jobs because of time missed for medical reasons.

Keep in mind that you may leave a clinical trial at any point. Be sure to talk with the clinical trial team before making a decision to stop your participation. They can help you with a problem.


What are the phases of clinical trials?

Before clinical trials can take place in people, new treatments must be researched in animals in a lab. This ensures new therapies meet safety requirements set by the federal Food and Drug Administration, or FDA. When safety research is completed and a therapy is approved, testing in people may begin.

New treatments go through four phases, or steps, of clinical trials. Each phase is considered a single clinical trial.

The FDA reviews the findings from each completed phase. If the results meet certain criteria and the FDA approves, the next phase can begin.

The first three phases of clinical trials are the most important in researching new treatments. They are:

Phase I

  • purpose: measures safety and dose, effective dose, or the safety of a combination of two medicines that have been used separately but never together. Phase I doesn’t test how well a medicine works to treat cancer
  • trial structure: not randomized, meaning everyone in the trial receives the medicine under study
  • people recruited: fewer than 50 who are healthy or have cancer. If they have cancer, it is likely other treatments no longer work to treat it.
  • length of phase: up to 1 year
  • how many treatments move on to phase II: 70 percent

Phase II

  • purpose: measures how well the treatment works and watches for side effects
  • trial structure: often not randomized but sometimes randomized, meaning whether you get the new therapy is decided by chance
  • people recruited: may involve fewer than 50 to up to several hundred people who have cancer; the size depends on the trial structure
  • length of phase: up to 2 years
  • how many treatments move on to phase III: 33 percent

Phase III

  • purpose: compares new, safe treatment to the current standard treatment and measures side effects
  • trial structure: usually randomized, meaning whether you get the new therapy is decided by chance
  • people recruited: several hundred to several thousand who are healthy or have cancer
  • length of phase: several years or more

FDA approval

After phase III is complete, the new treatment may receive FDA approval based on its findings. If it's approved, the medicine can be made and sold. It can take another year and a half to get FDA approval after phase III ends. In total, a new treatment can take between 8 and 10 years to move from phase I to FDA approval.

Phase IV

There also is a phase IV, which occurs after FDA approval.

  • purpose: monitor long-term side effects of new medicines; collect information on the benefits of medicines in a variety of people who may not have taken part in the clinical trial, such as older people or pregnant women
    • many trials have no phase IV

How can I find clinical trials?

There are several good ways to find breast cancer clinical trials you may be eligible for:

When you find trials that seem right for you, bring the details, including study number and sponsor, to your doctor and talk about your options.


Where do clinical trials take place?

Clinical trials vary greatly in size and scope. A clinical trial may be held at just one location or might be available in hundreds of places throughout the country or around the world.

Breast cancer clinical trials take place in:

Not every trial is available at every site. Researchers may run clinical trials in only one, or very few, places. Cancer researchers and healthcare providers have cooperative groups that offer certain studies in multiple locations in the U.S., North America or other regions, or internationally.

Where can I go?

You may be able to participate in a clinical trial at the hospital or treatment center where you currently get care. Or your doctor may belong to a cooperative oncology research group that conducts studies. If you can’t get the study treatment at your care center but are interested, you may want to seek a second opinion from a doctor who participates in clinical trials.

If you find a clinical trial at another location and enroll, the clinical trial doctor will communicate about your treatment with your current provider, if you wish. Sometimes it’s possible to go to the clinical trial site just for enrollment and testing and then receive treatment closer to home.

More doctors are holding clinical trials in local settings than in years past. You may find these at your local hospital or doctor’s office. This helps make clinical trials available to more people.


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Reviewed and updated: August 31, 2015

Reviewed by: Pallav K. Mehta, MD


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