Observational study of the efficacy and safety of first-line osimertinib and later treatments for uncommon epidermal growth factor receptor-activating mutation-positive advanced non-small cell lung cancer.
Osimertinib, a third-generation epidermal growth factor receptor (EGFR) tyrosine kinase inhibitor, is a first-line therapy for advanced or metastatic non-small cell lung cancer (NSCLC) with EGFR mutations, including both sensitizing and T790M resistance mutations. Its real-world efficacy against uncommon EGFR mutations remains under-researched.
The REIWA study, a multicentric, prospective, observational study conducted in Japan from September 2018 to August 2020, enrolled patients with advanced or recurrent EGFR mutation-positive NSCLC receiving osimertinib. Data on clinical outcomes, safety, disease progression, and subsequent treatments were collected for patients with uncommon EGFR mutations.
Of 583 patients receiving osimertinib, 39 (6.7%) had an uncommon EGFR mutation. The present study included 32 of these patients after excluding seven patients with an exon 20 insertion mutation. The overall objective response rate was 53.1% [95% confidence interval (CI): 36.4-69.1], and the disease control rate was 78.1% (95% CI: 61.0-89.3). The median progression-free survival was 9.4 months (95% CI: 5.0-20.0), and the median overall survival (OS) was 21.8 (95% CI: 14.4-NA) months. Notably, patients with an exon21 L861Q mutation had a significantly longer OS than those with an exon18 G719X mutation, the respective values being 37.8 and 9.7 months (hazard ratio: 0.29; 95% CI: 0.10-0.85; P = 0.02). The rate of grade 3 or worse adverse events was 10.3%. Seven out of 32 (21.9%) patients showed progression involving only the central nervous system.
Osimertinib demonstrated efficacy and tolerability in the clinical setting in patients with uncommon EGFR mutation-positive NSCLC.
Hirata T
,Watanabe K
,Hosomi Y
,Yoh K
,Usui K
,Kishi K
,Naka G
,Tamano S
,Uemura K
,Kunitoh H
... -
《-》
The efficacy of continuing osimertinib with platinum pemetrexed chemotherapy upon progression in patients with metastatic non-small cell lung cancer harboring sensitizing EGFR mutations.
For patients with EGFR mutant NSCLC who progress on osimertinib, the clinical benefit of continuing osimertinib with next line platinum pemetrexed chemotherapy remains unknown.
In this international, multi-center, retrospective cohort study, a total of 159 patients with EGFR mutant NSCLC who progressed on osimertinib and received platinum-pemetrexed therapy on progression from 2013 to 2023 were included. The data cutoff was December 31, 2023. Data analysis was conducted from January 2024 to June 2024. The primary endpoints were progression free survival (PFS) and overall survival (OS), analyzed using Kaplan-Meier methods. Multivariable Cox regression adjusting for patient-specific and cancer-specific factors was performed.
421 patients with EGFR mutant NSCLC with progression on osimertinib were identified, of which159 patients who met pre-specified inclusion criteria were divided into two groups: Cohort 1 (osimertinib + platinum-pemetrexed) included 50 patients (median [IQR] age, 59 [30 - 83] years; 36 [72.0 %] female; 11 [22.4 %] Asian) and Cohort 2 (platinum-pemetrexed alone) included 109 patients (median [IQR] age, 54 [25 - 80] years; 62 [56.9 %] female; 74 [64.9 %] Asian). Most patients were never smokers (Cohort 1, 37 [74.0 %]; Cohort 2, 66 [60.6 %]). One third of patients had baseline brain metastases (Cohort 1, 19 [38.0 %]; Cohort 2, 36 [38.3 %]). Both cohorts had a median of two prior lines of anti-cancer therapy. The addition of bevacizumab or immune checkpoint inhibitors (ICI) to next-line platinum-pemetrexed chemotherapy was more common in Cohort 2 (bevacizumab use, 30.3 % vs 8.0 %, p = 0.002; ICI use, 33.0 % vs 2.0 %, p = 0.001). With a median duration of follow up of 30 months, there was a significant PFS benefit to continuing osimertinib with next line platinum pemetrexed chemotherapy (9.0 vs 4.5 months; HR 0.49, 95 % CI 0.32 - 0.74, p = 0.0032), also seen in subset analyses of patients who received first line osimertinib (n = 55, 11.0 vs 6.2 months; HR 0.41, 95 % CI 0.25 - 0.73, p = 0.002). Among patients with EGFR mutant NSCLC without brain metastases after progression on osimertinib, we found that continuing osimertinib with next line platinum pemetrexed significantly reduced the median time to CNS progression (n = 38; 7.0 vs 4.1 months; HR 0.47, 95 % CI 0.48 - 0.98, p = 0.01). After adjusted analysis, there was no significant OS difference between Cohorts 1 and 2 (19 months vs 13 months; HR 0.92, 95 % CI 0.60 - 1.39, p = 0.68).
For patients with EGFR mutant NSCLC who progress on osimertinib, there is a significant PFS, but not OS, benefit to continuing osimertinib with next line platinum pemetrexed chemotherapy. The continuation of osimertinib with next line platinum pemetrexed chemotherapy appears to reduce the risk of CNS progression.
Patil T
,Gao D
,Watson A
,Sakamoto M
,Nie Y
,Gibson A
,Dean ML
,Yoder BA
,Miller E
,Stalker M
,Aisner DL
,Bunn PA
,Schenk EL
,Marmarelis ME
,Bennati C
,Navani V
,Zhang Y
,Camidge DR
... -
《-》