A United States-Based Real-World Study on Biomarker Testing and Rebiopsy Rates Among Patients With Non-Small Cell Lung Cancer Across Lines of Therapy.

[BACKGROUND] Comprehensive biomarker testing for patients with advanced/metastatic non-small cell lung cancer (a/mNSCLC) is essential for treatment decision-making. However, there is limited understanding of testing adoption across lines of therapy (LoT).

[MATERIALS AND METHODS] This retrospective real-world study used the ConcertAI Patient360™ NSCLC database in the US to assess biomarker testing patterns among adults with nonsquamous a/mNSCLC (2017-2022) who received ≥ 1 LoT with ≥ 90-day follow-up. Testing and rebiopsy rates for actionable biomarkers were analyzed by LoT (1L, 2L, 3L), test modality, and sample type.

[RESULTS] Of 4528 patients, 51% were female, 76% were White; the mean (SD) age at diagnosis was 67.2 (10.2) years. Testing rates for ≥ 1 biomarker were 85% (1L), 31% (2L), and 26% (3L). 1L IHC and 1L NGS testing rates were 52% and 57%, respectively (2017-2022). Tissue was tested most often in 1L; liquid biopsy was prioritized in 2L. Among patients who received corresponding LoT and any biomarker test for the prior line, Black patients had lower crude rates of 2L rebiopsy and male patients had significantly lower rates of 2L rebiopsy/testing. Adjusted odds ratio (95% CI) for rebiopsy was lower for patients with EGFR WT versus EGFR mutation at 2L (0.40 [0.28-0.59]; P < .001) and 3L (0.46 [0.24-0.89]; P = .020).

[CONCLUSIONS] While tissue was most frequently used in 1L testing, rebiopsy was less frequent in 2L + . Racial and sex differences in rebiopsy/testing rates were observed. Standardization for 2L + biomarker testing is needed to optimize later-line treatment decisions for patients with a/mNSCLC.