Biopsy Requirement for Enrollment in Clinical Trials Examined

Clinical trials are now requiring biopsy or archival tumor tissue submissions before enrollment.

Many trials are studying targeted therapies, which were created to specifically alter a certain alteration inside the tumor. This helps determine which patients are enrolled based on whether or not they have the specific alteration or biomarker.

From 2007 to 2015, investigators reviewed and tracked non-small cell lung cancer (NSCLC) patients with metastatic disease.

The study included 636 patients in 950 unique study encounters, along with some patients who enrolled in multiple trial studies. There were a total of 55 clinical trials, with 54 that were linked to therapy and 1 for biomarker analysis only.

There were 32 patients that allowed archival samples, while 6 mandated repeat biopsies. It was required that there be either a presence or a confirmation of a specific biomarker in 24 trials.

In the 54 trials that were linked to therapy, there were 549 potential study candidates who were screened. Sixty percent of the patients went on to receive treatment in the study.

There were more patients who received treatment in the trials with the mandatory tissue, versus those who did not (83% vs. 55%, p<0.0001). The study treatment was also started earlier (median 9 vs. 16 days, p=0.002).

In trials that allowed archival tissue, there were 59% who received therapy, while only 38% received therapy when a repeat biopsy was required (p=0.0007) and the amount of time from consent to therapy was shorter (median 14 days vs 54 days, p<0.001).

Investigators found the most common barriers to trial enrollment was absence of a required biomarker (34%), consent withdrawal (20%), deterioration/death (17%), other exclusion criteria (15%), and insufficient biopsy tissue (10%).

"The consequences of mandatory tumor tissue requirements in advanced NSCLC clinical trials with respect to accrual rates, potential time delays and patient attrition are sobering for investigators and patients,” said senior author of the study Natasha Leighl, MD. “Our study identifies a need to re-evaluate the role of research biopsies in clinical trials and to implement solutions that will improve patient access to investigational treatment by addressing mandatory tumor tissue requirements."