About 20% of newly diagnosed adult cancer patients in the US are eligible for clinical trials, studies for which people volunteer to test new drugs or other treatments. Yet only about 3% to 5% actually participate.

Why? Most people assume that clinical studies are an option for only the sickest patients for whom there are no effective treatments. Not true! The only requirement for many studies is having a specific type of cancer or being in a certain age group or other demographic category. Also, many people assume that one group in a study receives a placebo. The fact is that a placebo is not used in the vast majority of studies. In treatment studies, some patients are given the drug/procedure under investigation…others are given the best available standard treatment.

Here’s what else you need to know about clinical trials…

What’s Available?

At any given time, thousands of clinical trials are under way. The National Cancer Institute website alone lists more than 12,000 trials that are looking for participants. The studies that get the most attention are those that look at breakthrough cancer treatments, but that’s just the tip of the iceberg. Other trials compare single drugs with combination treatments…find new uses for old drugs…study new surgical techniques or radiation treatments, etc.

For some studies, all you have to do is give researchers permission to review your medical records. Example: Researchers at the Mayo Clinic Cancer Center learned from chart review studies that patients with chronic lymphocytic leukemia responded better to treatments when they had normal blood levels of vitamin D.


Typically, a computer will assign a participant to a group in a clinical trial. One group will be given the new drug/treatment. The control group will be given a standard treatment.

If you’re randomly assigned to the control group, you’ll still get the same treatment that you likely would have gotten if you hadn’t joined the study. Those in the “active” group will get something that’s expected to be at least as good—and possibly better.

The Risks

New drugs/procedures can have side effects or other complications that ­the researchers didn’t anticipate. Should you take the risk?

It’s a valid concern, particularly if it’s an early-phase study, with a lot of unknowns. But most treatment studies already have a long history. Cancer drugs typically have been studied for at least six years in the laboratory before they make it to clinical trials with humans. It may take another eight years before drugs are approved—or not—by the FDA.

Researchers may not know everything about the drug/treatment, but they know a lot by the time these studies begin. It’s always possible that the therapy being researched in the clinical trial is going to be less effective than the standard treatment. But typically study data is reviewed while the study is under way—and a study could be stopped because of side effects or because a treatment is not showing effectiveness.

My advice: If you are considering joining a particular study, ask the researchers how familiar they are with the treatment being researched. Some treatments have been used for other purposes for decades—they’re unlikely to bring too many surprises. The diabetes drug metformin, for example, now is being studied as a treatment for breast and ovarian ­cancers. Doctors are knowledgeable about the drug and the probable side effects.

How to Participate

Talk to your oncologist. In one poll, patients reported that 70% of their ­doctors never mentioned a clinical trial as an option. So ask. Even if your doctor isn’t personally involved in a clinical trial, he/she can talk you through the issues—the pros and cons of participating…where to look for studies that involve your type of cancer…and what the studies are likely to involve.

Helpful: For a list of cancer clinical trials, go to Cancer.gov/clinicaltrials.

Make the decision early. One of the first things you should ask your oncologist is how quickly you must make a decision about treatment options. Some studies accept only patients who haven’t started other treatments.

Important: If you decide to participate in a study, you can change your mind later. Patients can quit a study at any time.

Is it practical? Even if you would like to participate, you may find that it’s not a good fit. Example: A study might require weekly tests at a medical center hundreds of miles away. That’s not practical for most people. But other studies may involve monthly visits at a site closer to home. Or there may be times when routine blood work or imaging may be done at your local doctor’s office and results sent to the study team.

Study participants typically get more face time with doctors—along with additional checkups, tests, etc.—than patients who don’t participate in studies. One study found that 95% of those who participated in one clinical study said that they would consider doing so again.

Check the costs. Many tests and treatments will be paid for by the study sponsor—but that doesn’t mean all of your care is free. In most cases, you (or your insurer) still will be responsible for “routine” care costs—for example, routine blood work or scans. Travel expenses are rarely covered.

Under the Affordable Care Act, some health plans are required to cover the routine costs of study participants. Check with your insurance company, or contact your state’s Health Insurance Commission.

The 4 Phases of a Study

Before joining a clinical trial, ask about the study phase. This will give you some idea of how much is known about the treatment.

Phase 0 is the earliest stage. Small doses of a drug are tested in just a few people to find out if it reaches the tumor, how it’s metabolized, etc. A participant won’t benefit from a phase 0 study, but future patients might.

Phase 1 studies are used to determine the highest drug dose that can be given safely and identify possible side effects. Sometimes, these are referred to as “dosing” studies. Researchers also may make sure that the treatment has some benefit, such as slowing tumor growth.

Phase 2 trials involve slightly larger numbers of patients. The goal is to see if the treatment actually works—for example, if it causes a tumor to shrink. If enough patients benefit and side effects aren’t too much of a problem, the drug then may go on to the final stage.

Phase 3 studies look at anywhere from hundreds to thousands of patients. These are the treatment studies that most cancer patients join. If the drug is clearly effective, an application for approval is submitted to the FDA.