Authors:
Background:FDA approved N for previously treated squamous mNSCLC in 3/2015 and non-squamous mNSCLC in 10/2015 regardless of PD-L1 expression. P was approved for previously treated mNSCLC in 10/2015 for patients whose tumors express PD-L1 as determined by an FDA-approved companion diagnostic (CoDx). Post-FDA approval treatment patterns of N and P, including PD-L1 testing patterns, remain unclear.Methods:We conducted a retrospective analysis using de-identified patient-level electronic health record (EHR) data aggregated from USCPs by Flatiron Health in accordance to an institutional review board approved protocol. Data was abstracted using both structured and unstructured EHR content with 10% duplicate abstraction to confirm data quality. All patients in the database with clinically-confirmed mNSCLC diagnosed from 1/1/11 to 3/31/16 and documented order or administration of N or P were included in the analyses. PD-L1 expression testing results were abstracted from unstructured data in EHR documents.Results:Within the first year of FDA approval, 1,362 mNSCLC patients received N or P (96.2% N; 3.3% P, 0.5% N+P). The median duration of treatment was 113 days. Overall, 11.3% of patients were tested for PD-L1 expression, 42.2% of whom tested positive. PD-L1 expression testing increased quarterly (Q) from 3.0% in Q2 2015 to 12.8% in Q1 2016. An FDA-approved CoDx was used 30.5% of the time. Among patients who received N, 90.5% were not tested for PD-L1 expression, 3.2% tested positive, and 4.7% tested negative for PD-L1. Among patients who received P, 32.7% were not tested for PD-L1 expression, 50.0% tested positive, and 1.9% tested negative.Conclusions:We observed low rates of PD-L1 expression testing in USCPs for patients with mNSCLC receiving N or P. Testing rates increased quarterly following FDA-approval. The majority of patients were not tested using FDA-approved CoDx. Most patients who were not tested for PD-L1 expression or tested negative received N. Clinician education will be important as data on optimal PD-L1 testing strategies guiding immunotherapy treatment decisions accumulates.
Sources:
ASCO Annual Meeting