OSIRAM-1/TORG1833: Overall survival results of a randomized phase II study of osimertinib plus ramucirumab versus osimertinib alone as initial chemotherapy for EGFR mutation-positive non-squamous non-small cell lung cancer.

Abstract

8613 Background: Dual inhibition of the EGFR/VEGF pathways has demonstrated superior efficacy with 1st generation EGFR tyrosine kinase inhibitor (TKI) in patients with non-small cell lung cancer (NSCLC) harboring EGFR mutations. This study aims to evaluate the efficacy and safety of combining osimertinib (Osi), a 3rd generation TKI considered the standard of care, with ramucirumab (Ram). We have previously shown the result of progression free survival (PFS) as a primary endpoint, the median PFS was 20.0 months for Osi+Ram and 24.0 months for Osi, hazard ratio of 1.054 (95% CI 0.674-1.648). In further analyses, we aimed to examine the effects of this combination therapy on overall survival (OS). Methods: Previously untreated EGFR mutation-positive advanced non-squamous NSCLC patients with a performance status of 0 or 1 were eligible. Asymptomatic and/or treated brain metastases were included. Eligible patients were randomized at a 1:1 ratio to receive Osi (80mg) every day either without or with Ram (10mg/kg) every 2 weeks until disease progression or unacceptable toxicity, stratified according to gender and the type of EGFR mutation (exon 19 deletion, L858R). The primary endpoint was PFS assessed by the independent blinded radiologic reviewer. Secondary endpoints included PFS assessed locally, objective response rate (ORR), disease control rate (DCR), duration of response (DOR), OS and safety. Results: Between November 2018 and April 2020, 122 patients (Osi+Ram: 59, Osi: 63) were enrolled. The patients' characteristics were well balanced. 59% were females, and 61% had an exon 19 deletion. Median age was 70 years old (range, 29-86). With a median follow up of 36.0 months, the median OS was 43.4 months (95% CI 36.5-N.R.) for Osi+Ram and N.R. (95% CI 41.3-N.R.) for Osi, resulting in a hazard ratio of 1.159 (95% CI 0.645-2.083, p = 0.62). Median treatment duration for Ram was 140 (14-1239) days. Ram was discontinued in 45 patients (76%) by the treatment related adverse effects. Common reasons for Ram discontinuation were platelet count decreased (n=14), proteinuria (n=12), neutrophil count decreased (n=11), pneumonitis (n=3), bleeding (n=3) and infection (n=3). Pneumonitis was observed in 16% in Osi, 9% in Osi+Ram, with grade 3 observed in 2% of both arms. Conclusions: Both treatment arms demonstrated sustained OS over 43 months. However, this study did not show an advantage of biweekly Ram administration with Osi in terms of PFS and OS. Notably, there was surpassed increase of early discontinuation of Ram due to higher adverse events. Clinical trial information: 2080224085 .