Many patients are automatically excluded from lung cancer clinical trials due to previous cancer, according to findings.
Additionally, this criterion appears to be used in trials with a variety of characteristics, including more than two-thirds of trials with non-survival endpoints, the researchers wrote.
“Our research demonstrates that a substantial proportion of potential subjects are reflexively excluded from lung cancer clinical trials due to prior cancer,” researcher David Gerber, MD, associate professor of internal medicine in the division of hematology and oncology at the UT Southwestern Medical Center, said in a press release.
Due to the assumption that a prior cancer diagnosis could hamper clinical trial outcomes, cancer survivors are frequently excluded. To assess the prevalence of this trend in lung cancer clinical trials and its influence on trial accrual, Gerber and colleagues reviewed lung cancer clinical trials, including 13,072 patients, sponsored or endorsed by the ECOG for exclusion criteria related to a prior cancer diagnosis.
The researchers also projected prevalence of prior primary cancer diagnoses among lung cancer patients using SEER-Medicare linked data. For each trial, the researchers recorded the year of initiation, target patient accrual, trial phase, stage of cancer, histology, primary endpoint and main treatment modality.
In addition, the researchers documented whether previous separate primary cancers were grounds for exclusion and noted the time frame of exclusion.
According to study results, 80% of the clinical trials applied some degree of exclusion criteria to patients with a prior diagnosis of cancer. The trials excluded these patients as follows: any prior cancer (14%); cancer within 5 years (43%); within 2 to 3 years (7%); and patients with active cancer (16%).
The SEER database analysis found that among 210,509 patients, 56% of prior cancers were diagnosed 5 years before lung cancer diagnosis.
“The resulting impact on study accrual is sobering,” Gerber said in the release. “The proportion of potential patients excluded due to prior cancer per trial ranged up to 18%, with the estimated absolute number of excluded patients per trial ranging up to 207.”
Researchers observed that trials with survival primary endpoints exhibited a 94% exclusion rate of patients with prior cancer, and trials with non-survival primary endpoints had a 73% exclusion rate of patients with previous cancer (P=.06).
“If future studies demonstrate that prior cancer does not limit lung cancer treatment options or adversely impact clinical outcomes, modifying or eliminating this longstanding and arbitrary exclusion policy in lung cancer clinical trials may result in more generalizable results, faster accrual, higher completion rates, and the delivery of better treatments to more patients sooner,” Gerber said. “Because clinical trial design is relatively centralized, we believe that implementation of such changes could occur rapidly.”
Disclosure: \The researchers report no relevant financial disclosures.