A Randomized, Open-Label, Multicenter, Phase 3 Study of High-Dose Vitamin C Plus FOLFOX ± Bevacizumab versus FOLFOX ± Bevacizumab in Unresectable Untreated Metastatic Colorectal Cancer (VITALITY Study).

PURPOSE: To compare the efficacy and safety of high-dose vitamin C plus FOLFOX ± bevacizumab versus FOLFOX ± bevacizumab as first-line treatment in patients with metastatic colorectal cancer (mCRC). PATIENTS AND METHODS: Between 2017 and 2019, histologically confirmed patients with mCRC (n = 442) with normal glucose-6-phosphate dehydrogenase status and no prior treatment for metastatic disease were randomized (1:1) into a control (FOLFOX ± bevacizumab) and an experimental [high-dose vitamin C (1.5 g/kg/d, intravenously for 3 hours from D1 to D3) plus FOLFOX ± bevacizumab] group. Randomization was based on the primary tumor location and bevacizumab prescription. RESULTS: The progression-free survival (PFS) of the experimental group was not superior to the control group [median PFS, 8.6 vs. 8.3 months; HR, 0.86; 95% confidence interval (CI), 0.70-1.05; P = 0.1]. The objective response rate (ORR) and overall survival (OS) of the experimental and control groups were similar (ORR, 44.3% vs. 42.1%; P = 0.9; median OS, 20.7 vs. 19.7 months; P = 0.7). Grade 3 or higher treatment-related adverse events occurred in 33.5% and 30.3% of patients in the experimental and control groups, respectively. In prespecified subgroup analyses, patients with RAS mutation had significantly longer PFS (median PFS, 9.2 vs. 7.8 months; HR, 0.67; 95% CI, 0.50-0.91; P = 0.01) with vitamin C added to chemotherapy than with chemotherapy only. CONCLUSIONS: High-dose vitamin C plus chemotherapy failed to show superior PFS compared with chemotherapy in patients with mCRC as first-line treatment but may be beneficial in patients with mCRC harboring RAS mutation.

Phase III randomized, placebo-controlled, double-blind study of monosialotetrahexosylganglioside for the prevention of oxaliplatin-induced peripheral neurotoxicity in stage II/III colorectal cancer.

BACKGROUND: Monosialotetrahexosylganglioside (GM1) is a neuroprotective glycosphingolipid that repairs nerves. Oxaliplatin-based chemotherapy is neurotoxic. This study assessed the efficacy of GM1 for preventing oxaliplatin-induced peripheral neurotoxicity (OIPN) in colorectal cancer (CRC) patients receiving oxaliplatin-based chemotherapy. METHODS: In total, 196 patients with stage II/III CRC undergoing adjuvant chemotherapy with mFOLFOX6 were randomly assigned to intravenous GM1 or a placebo. The primary endpoint was the rate of grade 2 or worse cumulative neurotoxicity (NCI-CTCAE). The secondary endpoints were chronic cumulative neurotoxicity (EORTC QLQ-CIPN20), time to grade 2 neurotoxicity (NCI-CTCAE or the oxaliplatin-specific neuropathy scale), acute neurotoxicity (analog scale), rates of dose reduction or withdrawal due to OIPN, 3-year disease-free survival (DFS) and adverse events. RESULTS: There were no significant differences between the arms in the rate of NCI-CTCAE grade 2 or worse neurotoxicity (GM1: 33.7% vs placebo: 31.6%; P = .76) or neuropathy measured by the EORTC QLQ-CIPN20 or time to grade 2 neurotoxicity using NCI-CTCAE and the oxaliplatin-specific neuropathy scale. GM1 substantially decreased participant-reported acute neurotoxicity (sensitivity to cold items [P < .01], discomfort swallowing cold liquids [P < .01], throat discomfort [P < .01], muscle cramps [P < .01]). The rates of dose reduction or withdrawal were not significantly different between the arms (P = .08). The 3-year DFS rates were 85% and 83% in the GM1 and placebo arms, respectively (P = .19). There were no differences in toxicity between the arms. CONCLUSION: Patients receiving GM1 were less troubled by the symptoms of acute neuropathy. However, we do not support the use of GM1 to prevent cumulative neurotoxicity. (ClinicalTrials.gov number, NCT02251977).

Phase I study of high-dose ascorbic acid with mFOLFOX6 or FOLFIRI in patients with metastatic colorectal cancer or gastric cancer.

BACKGROUND: Preclinical studies suggest synergistic effectiveness of ascorbic acid (AA, vitamin C) and cytotoxic agents in gastrointestinal malignancies. This phase 1 study aimed to establish the maximum tolerated dose (MTD) and recommended phase 2 dose (RP2D) of AA combined with mFOLFOX6 or FOLFIRI regimens in patients with metastatic colorectal cancer (mCRC) or gastric cancer (mGC). METHODS: In the dose-escalation phase, patients received AA (0.2-1.5 g/kg, 3-h infusion, once daily, days 1-3) with mFOLFOX6 or FOLFIRI in a 14-day cycle until the MTD was reached. In the speed-expansion phase, AA was administered at the MTD or at 1.5 g/kg if the MTD was not reached at a fixed rate of 0.6, 0.8 or 1 g/min. Pharmacokinetics and preliminary efficacy were also assessed. RESULTS: Thirty-six patients were enrolled. The MTD was not reached. The RP2D was established as AA at 1.5 g/kg/day, days 1-3, with mFOLFOX6 or FOLFIRI. No dose-limiting toxicity (DLT) was detected during dose escalation. The most common treatment-emergent adverse events (TRAEs) were sensory neuropathy (50%), nausea (38.9%), vomiting (36.1%) and neutropenia (27.8%). Grade 3-4 TRAEs were neutropenia (13.9%), sensory neuropathy (2.8%), vomiting (2.8%), diarrhea (2.8%) and leukopenia (2.8%). AA exposure was dose-proportional. The objective response rate was 58.3%, and the disease control rate was 95.8%. No difference in efficacy was found between mCRC patients with wild-type RAS/BRAF and mutant RAS or BRAF. CONCLUSIONS: The favorable safety profile and preliminary efficacy of AA plus mFOLFOX6/FOLFIRI support further evaluation of this combination in mCRC or mGC. TRIAL REGISTRATION: ClinicalTrial.gov Identifier: NCT02969681 .