Genomic Testing and Targeted Therapies May be Underused in Community Practice, Study Shows

A review of patients with advanced non—small cell lung cancer (NSCLC) treated in a community practice setting demonstrated that not all patients recommended for receiving genomic testing are being appropriately tested for potential genetic drivers of disease.

Further, less than 50% of patients eligible to receive a targeted therapy due to a corresponding genetic driver had evidence of receiving the targeted treatment in any line of treatment, study authors noted in a poster presented at the 2019 ASCO Annual Meeting.

“Previous work has suggested that tissue insufficiency, cost/reimbursement challenges, poor performance status, and turnaround time may act as barriers to the uptake of comprehensive molecular testing, and given the continued low rates of testing seen in our study, we suggest that these barriers continue to present challenges to the widespread incorporation of comprehensive molecular testing into advanced NSCLC patient care,” the study authors, led by Hinco J. Gierman, PhD, of Integra Connect, wrote in their poster.

Prior research has demonstrated that most patients with advanced NSCLC were not receiving testing for all guideline-recommended genes. The study authors aimed to determine if testing rates were improved between 2017 and 2018 and to review the impact the findings had on patient care.

The investigators reviewed electronic medical records of 5 community practices through the Integra Connect database, which contains electronic medical records and claims data for approximately 600,000 patients with cancer. They identified 1203 patients with stage IIIb or IV NSCLC treated since January 1, 2017. The records were manually reviewed to find evidence of genetic testing and targeted treatment.

Of the 1203 patients, 52% were male, the majority (71%) were 65 years old or older, and three-quarters of the group were Caucasian. More than 80% of patients were current or former smokers, 14.4% were non-smokers.

Between 11% and 54% of the identified patients had any evidence of testing for at least 1 of the 7 genes recommended for testing by the National Comprehensive Cancer Network (NCCN) guidelines at the time:EGFR, ALK, ROS1, BRAF, RET, MET,andERBB2 (HER2).The first 4 genes all have FDA-approved targeted treatment options and the other 3 had related agents in development that were included in NCCN guidelines. Only 7% of patients received testing for all 7 of the mutations.

Overall, 54% received testing for alterations in theEGFRgene and the rates decreased for subsequent genes. Twenty-two percent of patients received testing for all 4 of the genes with on-label treatment options. Additionally, 48% underwent testing for PD-L1 expression.

When tested with tissue-based genotyping, these tests had a median time to results (TTR) of 14 days compared with a TTR of 4 days with blood-based tests.

Of the patients with a discovered targetable alteration inEGFR, ALK, ROS1,orBRAF,only 45% of these patients’ records demonstrated evidence of receiving a corresponding targeted therapy.

AnEGFRorALKalteration was found in 84 patients who had no evidence in their clinical records of receiving a targeted therapy prior to the start of immunotherapy. Thirty-seven percent of these patients went on to receive an immune checkpoint inhibitor. Among these patients, the genomic testing results were available prior to immunotherapy initiation for only 65%.

“Interestingly, counter to immune checkpoint inhibitor drug labels, we found that over one-third of patients with a targetable alteration inEGFRorALKand no evidence of progression on the corresponding tyrosine kinase inhibitor received an immune checkpoint inhibitor, with the majority of these patients known to have the targetable alteration at the time of immune checkpoint inhibitor initiation,” the study authors commented in the poster.

“Further research is needed to identify strategies to increase comprehensive testing of [patients with] advanced NSCLC and to better understand the obstacles that currently prevent these results from consistently being used to inform first-line treatment,” they added.

Reference:

Gierman HJ, Goldfarb S, Labrador M, et al. Genomic testing and treatment landscape in patients with advanced non-small cell lung cancer (aNSCLC) using real-world data from community oncology practices.J Clin Oncol. 2019;37(suppl; abstr 1585).