Abstract 81P
Background
Platinum-based chemotherapy is still the standard of care for Epidermal growth factor receptor (EGFR) mutated non-small cell lung cancer (NSCLC) patients after developing EGFR-TKI resistance. However, no study focusing on the role of PD-1 inhibitor based treatments for EGFR mutated NSCLC patients who carried PD-L1 TPS ≥ 50% progressed after EGFR-TKI therapy. Thus, we aimed to investigate the outcomes of PD-1 inhibitor based treatments for these patients and to explore the population that may benefited from PD-1 inhibitor based therapies.
Methods
We retrospectively collected data of EGFR mutated advanced NSCLC patients with PD-L1 TPS≥50% who have failed prior EGFR-TKI therapies without T790M mutation at Shanghai Chest Hospital between January 2018 and June 2021. Progression-free survival (PFS) and overall survival (OS) were utilized to evaluate the outcomes.
Results
A total of 146 patients were included. The median follow-up was 36.7 months (IQR, 12.5-44.2 months). Among the population, 66 patients (45.2%) received chemotherapy, the remaning (54.8%) received PD-1 inhibitor based therapies, including 56 patients(70.0%) received PD-1 inhibitor combined with chemotherapy (PC) and 24 patients (30.0%) received PD-1 inhibitor monotherapy (PM). Survival analysis shown that patients who received PD-1 inhibitor based therapies had better PFS and OS compared with those treated with other therapy (median PFS, 4.0 vs. 10.0 months, P＜0.001; median OS, 39.5 vs. 24.2 months, P＜0.001). What’s more, patients who treated with PC treatment had a superior survival time than those received PM treatment (median PFS, 10.3 vs. 7.0 months, P＜0.001; median OS, 32.4 vs. 41.6 months, P＜0.001). Subgroup analysis found that the PFS and OS benefit of PC was evident in all subgroups.
Conclusions
For advanced NSCLC patients with EGFR mutations and PD-L1 TPS≥50% who have failed prior EGFR-TKI therapies without T790M mutation, PD-1 inhibitor based treatment could provide a more favorable survival than classical chemotherapy. What's more, compared with PD-1 inhibitor monotherapy, PD-1 inhibitor combined with chemotherapy seems to be the preferred treatment.
Legal entity responsible for the study
The authors.
Funding
Shanghai Shenkang Organization.
Disclosure
All authors have declared no conflicts of interest.