How Are Eligibility Criteria for Clinical Trials Changing to Help People With Cancer?

June 10, 2021
Patty Spears

Patty Spears is an over 20-year breast cancer survivor and cancer research patient advocate. She has concentrated her advocacy on clinical trials. She is currently an advocate for the Alliance for Clinical Trials in Oncology as Associate Group Chair for Advocacy and a member of several National Cancer Institute Steering Committees. Patty is currently working as a patient advocate at the University of North Carolina Lineberger Comprehensive Cancer Center in Chapel Hill, North Carolina, where she leads the Patient Advocates for Research Council (PARC) and the Breast Specialized Program of Research Excellence (SPORE) Advocates. You can follow her on Twitter. View Patty’s disclosures.

Choosing whether to participate in a clinical trial is a big decision for a person with cancer to make. However, even if someone chooses a clinical trial, they may encounter barriers to joining that they have no control over. One of these barriers is that people with cancer must meet specific conditions, or have specific characteristics, before they can participate in a certain clinical trial. These conditions and characteristics are called the “eligibility criteria” of that study.

What are eligibility criteria in cancer clinical trials?

Eligibility criteria help ensure that people participating in a clinical trial are similar in terms of factors like the type of cancer they have and their general health. This is set in place so that the results of the clinical trial are not due to chance.

There are 2 types of eligibility criteria in every cancer clinical trial, the specifics of which differ from 1 trial to the next:

  1. Inclusion criteria. These are conditions a person with cancer must meet before joining the clinical trial. For example, 1 inclusion criteria may be that the person has to have a specific cancer type and stage, like “stage IV colon cancer” or “stage I kidney cancer.”
  2. Exclusion criteria. These are conditions a person with cancer cannot have in order to join the clinical trial. For example, the exclusion criteria may say that someone who is pregnant may not participate in the study.

How do eligibility criteria in clinical trials help keep participants safe?

Keeping people with cancer safe when they join a clinical trial is extremely important. Safety information about a treatment comes from previous clinical trials and other previous scientific studies about the treatment. For example, the criteria may exclude people who are more likely to have severe or life-threatening side effects because they also have another, specific health condition. Meanwhile, some clinical trials only allow people who are most likely to benefit from what is being studied to join the trial. For instance, this is common in clinical trials looking at targeted treatments that only work when the person’s tumor has a known change (mutation) in a specific gene.

However, any clinical trial comes with its own risks. Be sure to discuss with your doctor any potential harms and benefits of joining a specific clinical trial you are interested in. Your doctor can help you understand the eligibility criteria used to quality for that study, how your disease and current health might affect your eligibility, and how you are likely to be affected by a treatment, especially if you have other health conditions like diabetes or high blood pressure. Understanding these different aspects of joining a clinical trial can help you decide whether participating is right for you.

How are eligibility criteria for clinical trials changing to help more people with cancer?

Sometimes, inclusion and exclusion criteria mean there are people who cannot join a clinical trial even though they may benefit from the new treatment and it may be safe for them. When people look for a clinical trial as a treatment option, it is frustrating when they find out they cannot qualify.

Because of this, several groups are working together to determine how to best adapt eligibility criteria to include more people with cancer. Namely, broadening eligibility criteria could allow more people with cancer to qualify for clinical trials. By allowing more types of people to join, this could make the results of the clinical trial more relevant to those who would eventually get the treatment. It could also increase early access to new treatments for more people who may benefit from such treatment.

A recent study looked at whether broadening eligibility criteria could allow more people with cancer to join a clinical trial. The study found that broadening 3 common criteria currently used (whether the cancer had spread to the brain, whether there was no spread to other parts of the body, and whether the kidneys were functioning properly) allowed more people to join the clinical trial. The number of people who could join the clinical trial doubled using the broader criteria. These changes also resulted in participants being more representative of people with that specific type of cancer. Overall, broadening the eligibility criteria led to a larger, more diverse group of patients.

The American Society of Clinical Oncology (ASCO), Friends of Cancer Research, and the U.S. Food and Drug Administration (FDA) are 1 example of a group working together to expand eligibility criteria. They have created working groups to look at specific conditions used to qualify patients for clinical trials and develop recommendations about how to broaden the conditions used to include or exclude patients.

Eligibility criteria that keep patients safe are essential for clinical trials. But adapting and broadening eligibility criteria are important steps toward allowing as many people as possible to safely participate in clinical trials.

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