Riluzole in Combination with mFOLFOX6 and Bevacizumab in Treating Patients with Metastatic Colorectal Cancer: A Phase 1 Clinical Trial

Abstract

BACKGROUND: Colorectal cancer (CRC) is the second leading cause of cancer-related mortality in the US. 5-fluorouracil (5-FU)-based chemotherapies in combination with targeted agents remain the standard of care in patients with metastatic or locally advanced disease. New treatment strategies are needed for metastatic CRC patients with microsatellite stable disease. Preclinical studies showed that riluzole, an oral medicine for amyotrophic lateral sclerosis, inhibits glutamate release and synergizes with 5-FU to reduce cell viability in CRC cell lines. METHODS: In this single-arm, phase 1 trial of riluzole in combination with mFOLFOX6/bevacizumab for patients with metastatic CRC, the riluzole dose started at 50 mg twice daily, escalating to 100 mg twice daily or de-escalating to 50 mg once daily. Patients received riluzole for 16 weeks in combination with mFOLOFX6/bevacizumab for 8 cycles. Patients then either continued mFOLFOX6/bevacizumab or switched therapy. RESULTS: Twelve of the 14 patients enrolled were evaluable. All patients previously received FOLFOX, and 5 patients (41.7%) showed disease resistance to it. Two patients obtained partial responses, 9 had stable disease, and 1 had progressive disease. The objective response rate was 16.7%, and the disease control rate was 91.7%. The median duration of response was 4.9 months (95% CI 1.6-9.8). Median progression-free survival and overall survival were 4.89 and 12.98 months, respectively. CONCLUSION: Our study showed that riluzole plus mFOLFOX6/bevacizumab is well tolerated in patients with metastatic CRC and may have clinical activity in patients whose disease is resistant to FOLFOX.