Beyond the clinical trial: Real-world treatment patterns and drivers of PD-(L)1 therapy use in first-line metastatic NSCLC.

BACKGROUND: Immunotherapies have improved survival in patients with metastatic non-small cell lung cancer (mNSCLC), yet a substantial fraction of eligible patients remain untreated with immunotherapy in routine clinical practice. This study examined treatment patterns and factors associated with receipt of non-immunotherapy-containing first-line (1L) regimens among patients with mNSCLC not eligible for targeted therapies. METHODS: This retrospective, observational study used the Flatiron Health Research Database and included patients diagnosed with mNSCLC not eligible for targeted therapy who initiated 1L treatment on or after July 1, 2019 (data cutoff: September 30, 2023). Treatment patterns, classified by inclusion of an FDA-approved immunotherapy, and patient and disease characteristics were summarized. Logistic regression was used to identify factors that were associated with receipt of a non-immunotherapy-containing 1L regimen. RESULTS: In total, 13,223 patients were included in the study. Overall, 25% received a non-immunotherapy-containing 1L regimen, which was similar across study years. Platinum-based chemotherapy was the most common non-immunotherapy-containing 1L regimen. In a multivariable model, a wide range of factors were associated with use of non-immunotherapy-containing 1L regimens, including age, ethnicity, year of diagnosis, programmed death-ligand 1 (PD-L1) expression status, prior treatment with immunotherapy, practice type, geographical region, smoking status, and stage at initial diagnosis. CONCLUSIONS: A sizeable proportion of patients with mNSCLC continue to receive non-immunotherapy-containing 1L regimens, despite widespread availability and guideline recommendations as the preferred 1L therapy. These findings suggest that non-use of immunotherapy is influenced by clinical and structural factors, highlighting persistent gaps in equitable access to 1L immunotherapy.