Phase I Study of the Liposomal Formulation of Eribulin (E7389-LF): Results from the Advanced Gastric Cancer Expansion Cohort

PURPOSE: In the dose-expansion part of this open-label, phase I study, we explored the efficacy and safety of E7389-LF (liposomal formulation of eribulin) in Japanese patients with advanced gastric cancer. PATIENTS AND METHODS: Patients with advanced gastric cancer who had been previously treated with ≥2 lines of chemotherapy received E7389-LF 2.0 mg/m(2) every 3 weeks (the previously determined maximum tolerated dose, the primary objective of Study 114). Secondary objectives included objective response rate (ORR), progression-free survival (PFS), and safety; exploratory objectives included disease control rate (DCR) and clinical benefit rate (CBR), as well as pharmacodynamic measurements of serum biomarkers. RESULTS: As of June 24, 2021, 34 patients were enrolled and treated (10 from the original dose-expansion cohort, expanded to include 24 additional patients). Six patients had partial responses, for an ORR of 17.6% [95% confidence interval (CI), 6.8–34.5], and the median PFS was 3.7 months (95% CI, 2.7–4.8). The DCR was 79.4% (95% CI, 62.1–91.3), and the CBR was 32.4% (95% CI, 17.4–50.5). Overall, 32 patients (94.1%) experienced treatment-related adverse events, and 26 patients (76.5%) experienced grade ≥3 events, most commonly neutropenia (41.2%) and leukopenia (29.4%). Of the 8 endothelial cell/vasculature markers tested in this study, 7 were significantly increased among patients treated with E7389-LF; these changes were generally consistent regardless of best overall response. CONCLUSIONS: E7389-LF 2.0 mg/m(2) every 3 weeks was tolerable and showed preliminary activity for the treatment of patients with gastric cancer.