Impact of First-Line Maintenance Immunotherapy With or Without Pemetrexed for Non-Squamous Advanced/Metastatic Non-Small Cell Lung Cancer Lacking Targetable Mutations: A Real-World Analysis in England.

[OBJECTIVES] Real-world analyses of first-line maintenance (1LM) immuno-oncology (IO) treatment with or without pemetrexed for patients with non-squamous (NSQ) advanced/metastatic non-small cell cancer (a/mNSCLC), including the relative impact of 1LM pemetrexed, are lacking. This retrospective analysis describes 1LM treatment patterns and their outcomes in England.

[METHODS] Data from the National Disease Registration Service were collated to identify 2 cohorts of patients with NSQ a/mNSCLC completing ≥ 4 cycles of first-line (1L) platinum-based chemotherapy with IO plus pemetrexed, diagnosed from 1 March to 31 December 2019 (Cohort 1), or during a period where interim coronavirus disease 2019 (COVID-19) guidelines were in effect (1 March to 31 December 2020; Cohort 2). Baseline characteristics, 1LM treatment, overall survival (OS) and time to next treatment or death in both cohorts, and in a combined cohort of patients receiving 1LM stratified by the presence/absence of 1LM pemetrexed, were analyzed.

[RESULTS] Overall, 595 and 516 NSQ a/mNSCLC patients were included in Cohorts 1 and 2, respectively. Median OS (95% confidence interval [CI], months) from start of 1L was numerically longer in Cohort 1 (19.5 [17.6-22.2] months) versus Cohort 2 (15.7 [14.2-18.0] months). Combined (Cohort 1 and Cohort 2) median OS from 1L was broadly similar irrespective of pemetrexed presence (19.5 [17.5-21.6] months) or absence (18.6 [15.6-23.0] months) in 1LM.

[CONCLUSIONS] Survival was numerically shorter for patients diagnosed during the COVID-19 pandemic (Cohort 2; interim guidance) versus Cohort 1 (pre-COVID-19). In a combined cohort, survival was broadly similar regardless of 1LM pemetrexed use.