A Multicenter, Phase II Trial of Schedule Modification for Nab-Paclitaxel in Combination with Ramucirumab for Patients with Previously Treated Advanced Gastric or Gastroesophageal Junction Cancer: The B-RAX Trial (JACCRO GC-09).

ABSTRACT

BACKGROUND: This study investigated whether schedule modification of bi-weekly nanoparticle albumin-bound paclitaxel (nab-PTX) plus ramucirumab (RAM) is efficacious against gastric cancer (GC) or gastroesophageal junction cancer (GJC). PATIENTS AND METHODS: Patients with unresectable GC or GJC who were previously treated with fluoropyrimidine-containing regimens received nab-PTX (100 mg/m2) on days 1, 8, and 15 and RAM (8 mg/kg) on days 1 and 15 of a 28-day cycle. Based on the incidence of severe adverse events (AEs) during the first cycle, patients were modified to bi-weekly therapy from the second cycle. The primary endpoint was progression-free survival (PFS) in the bi-weekly therapy population. Based on the hypothesis that bi-weekly nab-PTX plus RAM would improve PFS from 4.5 to 7.0 months, 40 patients were required for power of 0.8 with a one-sided α of 0.05. RESULTS: Of the 81 patients enrolled, 47 patients (58%) were assigned to bi-weekly therapy. Patient characteristics were Eastern Cooperative Oncology Group performance status of 1 (19%) and diffuse type (45%). Median PFS was 4.7 months (95% confidence interval [CI] 3.7-5.6 months) and overall response rate was 25% (95% CI 11-39%). Severe AEs of grade 3 or worse were mainly neutropenia (83%) and hypertension (23%). EQ-5D scores were maintained during the treatment. In patients who continued standard-schedule therapy, median PFS was 2.7 months (95% CI 1.8-4.0 months). CONCLUSIONS: The primary endpoint for PFS was statistically not met, but modification of nab-PTX plus RAM to a bi-weekly schedule might be a feasible treatment option as second-line treatment for advanced GC/GJC patients, especially elderly patients, with severe AEs during the first cycle.