Older Adults Remain Underrepresented in Cancer Clinical Trials

Older adults were underrepresented in a large sample of cancer clinical trials, according to a recent study.

The researchers looked at data from more than 1,200 individual studies conducted by the Alliance for Clinical Trials on Oncology group. They included 237 suitable studies for this analysis, including 66,708 patients; the median age of trial participants was 60 years.

Each trial’s expected percent of participants aged 65 or older was calculated using data from the SEER (Surveillance, Epidemiology, and End Results) database. On average, the expected percentage of participants aged 65 or older was higher than the actual percentage enrolled (58% vs. 39%; P<0.0001). For hematology trials the average expected rate would be 53%, whereas the actual enrollment percentage was 37%.

Multivariable analyses showed that non-genitourinary cancer types (P<0.001), trimodality or more trials (P=0.009), and phase 2 trials (P=0.05) trials were all associated with larger enrollment disparity differences.

The researchers acknowledged that several perceived and actual barriers exist to enrolling older patients into clinical trials. However, it is hoped that education of researchers and patients on these barriers will “soon improve older adult enrollment to trials in the US.”

“The results of this study and others can be used to help design future trials to improve older adult enrollment onto standard-setting trials,” study authors wrote. “Improvement in trial design combined with educational efforts and continued data collection on older adult enrollment should lead to improved enrollment and ultimately improved care for a growing population of older adults with cancer.”