Crizotinib in patients with advanced or metastatic ROS1-rearranged lung cancer (EUCROSS): A European phase II clinical trial–Updated report on progression-free and overall survival.

Abstract

9066 Background: ROS1 rearrangements are found in 1% of non-small cell lung cancer (NSCLC) patients. Early clinical trials in the US and East Asia have proven the therapeutic efficacy of crizotinib in this subset of patients. EUCROSS is the first prospective European trial to evaluate the acitivity of crizotinib in ROS1-positive lung cancer. Here we present an updated analysis of the investigator-assessed progression-free survival (PFS) and overall survival (OS). Methods: EUCROSS is a multi-centre, single arm phase 2 trial (NCT02183870). Key eligibility criteria: ≥18 years of age, advanced/metastatic lung cancer, centrally confirmed ROS1-rearranged (fluorescence-in situ hybridisation). Treatment with crizotinib was initiated at a dose of 250 mg twice daily. Primary endpoint of the trial: investigator-assessed objective response rate (ORR) in the response-evaluable population (Response Evaluation Criteria in Solid Tumors, version 1.1). Key endpoints of this report: updated PFS and OS and updated molecular characterization of tumour tissue. Results: Thirty-four patients received treatment with crizotinib and were included in the intention-to-treat analysis. Four patients were excluded from the primary endpoint analysis due to violation of eligibility criteria (response-evaluable set, N = 30). Median follow-up period was 44.9 months. At the time of data cut-off for this report 19 patients (63%) discontinued treatment due to progression or death. Investigator ORR was 70% (95% CI, 51–85; 21/30), disease control rate was 90% (95% CI, 73.5-97.9; 27/30) and median PFS was 19.4 months (95% CI, 10.1-31.2). Median OS was not reached, but 24-months-OS probability was 66% (95% CI, 48.3-82.9). Tissue of 18 patients was available for hybrid-capture-based sequencing. Co-occurring genetic aberrations were found in 61% (11/18). TP53 mutations were most frequent (28%; 5/18). PFS (24-months probability, TP53-mut. 0% vs. TP53 wild-type (wt) 61%; p = 0.0219) and OS (24-months, TP53-mut. 40% vs. TP53 wt 83%; p = 0.015) were significantly shorter in TP53-mutant patients. Differences in OS and PFS stratified by number of prior treatment lines (0-1 vs. > = 2), brain metastases (yes vs. no) or CD74-rearrangement ( CD74- ROS1 vs. other fusion type) status were not significant. Conclusions: Updated PFS and OS results show that crizotinib is highly effective in ROS1-rearranged lung cancer. Co-occurring TP53 mutations were associated with a significantly worse outcome. Clinical trial information: NCT02183870.