Pemetrexed and platinum plus pembrolizumab in patients with metastatic non-squamous non-small cell lung cancer by tumor burden at baseline: A post-hoc efficacy analysis of KEYNOTE-189

Document Type

Conference Proceeding

Publication Date


Publication Title

Cancer Res


Background: Pemetrexed (pem) and platinum (plat) plus pembrolizumab (pembro) showed clinical improvement in metastatic nonsquamous (NSQ) non-small-cell lung cancer (NSCLC). The aim of this analysis was to assess the clinical benefit of pem+plat+pembro in patients by tumor burden at baseline. Methods: The intention-to-treat population was analysed. Patients were randomized pem+plat+pembro (n=410) or pem+plat+placebo (n=206). The data cut-off date was May 20, 2019. OS, PFS, PFS-2, and ORR were evaluated by Kaplan-Meier and univariate Cox methods within subgroups identified by extent of distant metastasis (M1a vs. M1b), median number (≤3 vs. >3) of organ systems with lesions, and severity score of patient-reported symptoms (below median vs. above median) at baseline. These subgroup analyses were also replicated within PD-L1 TPS subgroups (<1%, 1-49%, ≥50%). Results: A consistent benefit in OS, PFS, PFS-2 and ORR was observed in the pem+plat+pembro treatment arm, compared to the pem+plat+placebo arm, irrespective of staging (M1a vs. M1b), number (≤ 3 vs. 3) of organ systems with lesions and severity of patient-reported symptoms (Table 1). Results by PD-L1 expression in the subgroups were generally consistent regardless of the level of expression. Conclusions: Pem+plat+pembro demonstrated consistent clinical benefit across all subgroups analysed regardless of baseline tumor burden. These results continue to support pem+plat+pembro as a standard of care in metastatic NSQ-NSCLC.

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Not assigned.