Treatment of non-small-cell lung cancer after progression on nivolumab or pembrolizumab

Background Although PD-1 antibodies (PD1 Ab) are the standard of care for advanced non-small-cell lung cancer (aNSCLC), most patients will progress. We compared survival outcomes for patients with aNSCLC who received systemic therapy (ST) after progression and for those who did not. Additionally, clinical characteristics that predicted receipt of ST after PD1 Ab failure were evaluated. Methods All patients with aNSCLC in British Columbia initiated on nivolumab or pembrolizumab between June 2015 and November 2017, with subsequent progression, were identified. Eligibility criteria for additional ST included an Eastern Cooperative Oncology Group (ECOG) performance status (PS) of 3 or less and survival for more than 30 days from the last PD1 Ab treatment. Post-progression survival (PPS) was assessed by landmark analysis. Baseline characteristics associated with PPS were identified by multivariable analysis. Results Of 94 patients meeting the eligibility criteria, 33 received ST after progression. In 75.6%, a PD1 Ab was received as first- or second-line treatment. The most common STS were erlotinib (36.4%) and docetaxel (27.3%). No statistically significant difference in median PPS was observed between patients who did and did not receive ST within 30 days of their last PD1 Ab treatment (6.9 months vs. 3.6 months, log-rank p = 0.15.) In multivariable analysis, factors associated with increased PPS included an ECOG PS of 0 or 1 compared with 2 or 3 [hazard ratio (HR): 0.42; 95% confidence interval (CI): 0.24 to 0.73; p = 0.002] and any response compared with no response to PD1 Ab (HR: 0.54; 95% CI: 0.33 to 0.90; p = 0.02). Conclusions In this cohort, only 35.1% of patients eligible for post-PD1 Ab therapy received ST. Post-progression survival was not significantly affected by receipt of post-progression therapy. Prospective trials are needed to clarify the benefit of post-PD1 Ab treatments.