Front-line use of FOLFOXIRI plus bevacizumab and subsequent therapies in metastatic colorectal cancer (mCRC).

Abstract

45 Background: Emerging data shows that the higher incidence of mCRC in younger patients (pts) is accompanied by more aggressive front-line treatment with chemotherapies, such as FOLFOXIRI+bevacizumab (triplet+bev). We explored the use of triplet+bev and subsequent therapies in a representative sample of community practices in the USA. Methods: This was a retrospective study using the nationwide de-identified Flatiron Health Electronic Health Record-derived database from January 1, 2013, to February 28, 2023. The use of triplet+bev and subsequent treatments were analyzed in pts with newly diagnosed mCRC (≥18 years [yrs] of age) by oncologist-defined, rule-based line of treatment (LOT) and age (18–49, 50–64, and ≥65 yrs). Results: Of 24,285 eligible pts, 14%, 37%, and 49% were 18–49, 50–64, and ≥65 yrs at treatment initiation, respectively (Table). Triplet+bev use in any LOT was the most prevalent in the youngest age group (18–49 yrs) at 7% (Table). Two-thirds (67%) received triplet+bev in first line (1L) and 23% in second line (2L), 57% were male, and 34% had a KRAS mutation (23% missing). From 2013 to 2022, triplet+bev use in newly treated pts increased; this trend was more pronounced in pts 18–49 yrs (Table). Among pts not censored before the end of the respective LOT, median duration of 1L and 2L triplet+bev was 25.1 and 21.6 weeks, respectively (Table). For non-censored pts with and without a KRAS mutation, respectively, median duration of triplet+bev was 26.1 vs 23.5 weeks in 1L and 21.6 vs 16.5 weeks in 2L. Most frequently used new agents after 1L triplet+bev included anti-EGFR (panitumumab or cetuximab; 19%), TAS-102 (12%), regorafenib (10%), and capecitabine (3%). Most frequently used new agents after 2L triplet+bev were TAS-102 (21%), anti-EGFR (17%), regorafenib (15%), and pembrolizumab (8%). Conclusions: Our study shows that the use of triplet+bev has increased in pts with mCRC over time, particularly in those <50 yrs. Most frequent subsequent therapies across all pts following 1L and 2L triplet+bev included TAS-102, anti-EGFR, and regorafenib. Future research is needed to identify the optimal treatment strategies after triplet+bev. [Table: see text]