Are Eligibility Criteria in Clinical Trials Too Restrictive?


April 2018

Are Eligibility Criteria in Clinical Trials Too Restrictive?

It’s an issue that’s been hotly contested in the medical field for quite some time. And with good reason.

According to an article from Nature, nearly 20 percent of publicly funded clinical trials in the U.S. are delayed because they cannot register enough participants. These trials often stem from the extensive list of inclusion and exclusion criteria patients must pass to qualify and cannot.

Because these cancer clinical trials are meant to enhance our medical knowledge and to gain approval, however, there must be strict and controlled guidelines in place for participation. But some trials are so intensive that they cannot even accrue enough participants to conduct the study, and in turn are suspended. The issue to be brought forward, then, is whether drug makers can create a framework that’s controlled yet balanced. What level of rigor is needed to guarantee the value of the data, but does not unduly restrict enrollment?

To address the growing concerns over eligibility criteria, and worries that delays in data gathering may ultimately delay access to life saving drugs for cancer patients, the Food and Drug Administration convened in Washington D.C. for a public meeting titled “Evaluating Inclusion and Exclusion Criteria in Clinical Trials” on April 16.

The objectives of this meeting were to consider “eligibility criteria in clinical trials and their potential impact on patient access to investigational drugs, and how to facilitate the enrollment of a diverse patient population.”

While there are good and valid reasons to exclude a patient from a certain cancer clinical trial, there are other times where the process can be so exhaustive that by the time the patient receives the go-ahead it’s often too late for them to benefit from the therapy.

That’s not to say there shouldn’t be a framework for enrollment; there needs to be a balance of risk to benefit. For example, criteria designed to restrict a younger population because of the drug’s potentially harmful byproducts may seem reasonable, but in a case where there are no approved treatments and the prognosis looks grim, then perhaps eligibility criteria should be loosened.

The ongoing debate over balancing eligibility criteria against enrollment goals and benefit to patients is complicated, but it’s a debate worth having with the goals of better defining delicate balance.