Background: Monosialotetrahexosylganglioside (GM1) is a glycosphingolipid, which has antioxidant and neuroprotective properties. Cumulative neurotoxicity is a prominent toxicity of oxaliplatin-based therapy. This study was designed to assess the efficacy of GM1 for preventing oxaliplatin-induced neurotoxicity in colorectal cancer (CRC) patients. Methods: A total of 186 patients with stage II/III CRC undergoing adjuvant chemotherapy with modified FOLFOX6 (fluorouracil, leucovorin, and oxaliplatin) were randomly assigned to intravenous GM1 80mg per day or placebo from day 0 to day 4 during chemotherapy. The primary end point was the rate of grade 2 or worse cumulative neurotoxicity, measured by investigator using the National Cancer Institute Common Terminology Criteria for Adverse Events (NCI-CTCAE) version 4.0. The secondary end point were the chronic cumulative neurotoxicity measured by the European Organization for Research and Treatment of Cancer Quality of Life Questionnaire-Chemotherapy-Induced Peripheral Neuropathy 20 (EORTC QLQ-CIPN20), time to grade 2 neurotoxicity by using the NCI-CTCAE or the oxaliplatin-specific neuropathy scale, the rates of acute neurotoxicity measured by a numerical analog scale ranging from 0 to 10, and the rates of dose reduction or withdrawal of both arms. Results: There were no statistically significant differences in the rate of NCI-CTCAE grade 2 or worse neurotoxicity between the study arms (GM1: 33.7% vs. placebo: 31.6%; P= 0.76). Similarly, there were no significant differences measured by EORTC QLQ-CIPN20 neuropathy scale (P= 0.89) or additional measures of neuropathy, including measurement of the time to grade 2 neurotoxicity by using the NCI-CTCAE (P= 0.99) or an oxaliplatin-specific neuropathy scale (P= 0.98). In addition, GM1 did not substantially decrease oxaliplatin-induced acute neuropathy. The rates of dose reduction or withdrawal of both arms were not significantly different (GM1: 64.6% vs. placebo: 54.6%, P= 0.15). Conclusions: This study does not support using GM1 to prevent oxaliplatin-induced neurotoxicity. (NCT02251977) Clinical trial information: NCT02251977