9059 Background: Several tests measuring programmed cell death ligand 1 (PD-L1) expression are available to select patients with advanced non-small cell lung cancer (aNSCLC) for PD-1 axis therapy including FDA approved companion diagnostics (CoDx), as well as complementary (CyDx) and laboratory developed tests (LDTs). However, it is unknown how rapidly PD-L1 expression testing has become adopted, which type of tests are used, or whether testing affects first-line therapy. Methods: We retrospectively reviewed the Flatiron Health electronic health record-derived database, reflecting real-world care at community oncology practices in the U.S. We evaluated trends in the use of PD-L1 expression testing within 12 months of diagnosis. Among patients diagnosed after FDA approval of PD-L1 testing prior to first-line therapy (Oct 2016), and without other identifiable driver mutations, we used multivariable logistic regression to examine the association between PD-L1 testing and receipt of first-line PD-1 axis therapy. We further examined the association between PD-L1 expression result (using overall reported status or % staining) and choice of first-line therapy. Results: We identified 49,546 patients with aNSCLC from 2011 through the third quarter of 2018. The use of PD-L1 expression testing increased from 7.0% in 2015 to 70.6% in 2017 (p < 0.01). Among those receiving testing, the proportion of patients receiving CoDx increased from 29.9% in 2015 to 73.0% in 2017 with corresponding reductions in CyDx and LDTs. PD-L1 expression testing was associated with use of PD1-axis therapy in the first-line (OR = 2.92, 95% CI 2.59-3.30). Among 4,942 treated patients diagnosed after Oct 2016, those with ≥50% staining more frequently received first line PD-1 axis therapy (82.9%) than those with intermediate (35.5%) or low (25.8%) positive staining; conversely, patients with ≥50% were less likely to receive chemotherapy alone or combination with PD-1 axis therapy. Conclusions: PD-L1 expression testing was rapidly adopted following FDA approval of companion diagnostic testing for aNSCLC. Although the results of PD-L1 expression testing inform the choice of first-line therapy, a substantial proportion of patients are not tested prior to first line treatment.
Randomized phase II trial of two different schedules of docetaxel plus cisplatin as first-line therapy in advanced nonsmall cell lung cancer