Mortality among EGFR-mutated advanced NSCLC patients after frontline osimertinib treatment: A real-world, US attrition analysis

The recommended frontline therapy for patients (pts) with epidermal growth factor receptor-mutated (EGFRm) advanced NSCLC is osimertinib (osi), a 3rd-generation (gen) EGFR tyrosine kinase inhibitor (TKI); however, most will develop resistance. Approximately 28% of frontline pts treated with a 1st/2nd-gen EGFR TKI die before receiving a 2nd line of therapy (LOT) (Nieva Drugs Real World Outcomes 2022; 9:333–345). This analysis estimated mortality in EGFRm NSCLC after starting frontline osi and before 2nd LOT to determine if there is an improvement to historical rates. Data from the ConcertAI (Cambridge, MA) Patient360 NSCLC database (>100 geographically dispersed community US oncology practices) were analyzed descriptively. Included pts were diagnosed with advanced NSCLC between 1 Jan 2018 and 16 Aug 2022, had confirmed EGFR exon 19 deletions (ex19del) or exon 21 L858R mutations, and received osi (primary analysis) or 1st/2nd-gen EGFR TKI (ie, afatinib, erlotinib, or gefitinib) as frontline monotherapy. In the ConcertAI Patient360 database, 1,135 pts had confirmed EGFR ex19del or L858R; of which 467 (41%) received osi as frontline monotherapy. Among this frontline osi population, 119 (25%) died before receiving a subsequent LOT. Documented start of a 2nd LOT was observed in 133 (28%) of frontline osi-treated pts. The remaining 215 (46%) did not have documented start of a 2nd LOT, which could be due to ongoing frontline use. A similar proportion of frontline 1st/2nd-gen EGFR TKI pts died prior to a 2nd LOT (20%; table). Survival outcomes will be presented at the meeting. These results are also being evaluated in a 2nd dataset, which may be available at time of presentation. Table 19PPatient attritionOf patients receiving frontline, n (%)Osimertinib (n = 467)1st or 2nd-gen EGFR TKI (n = 61)aCross-cohort analysis was not conducted, and therefore, confounding factors cannot be ruled out.Median follow-up2.1 years2.9 yearsDied during frontline119 (25)12 (20)No documented start of 2nd LOT215 (46)8 (13)Started 2 nd LOT133 (28)41 (67)a Cross-cohort analysis was not conducted, and therefore, confounding factors cannot be ruled out. Open table in a new tab The proportion of EGFRm NSCLC pts dying while on frontline osi (25%) remains high, demonstrating many never get to a 2nd LOT. Further optimization of frontline therapy is needed to improve patient outcomes.