The Purpose of This Study is to Determine if Tetrodotoxin (TTX) is Effective in the Treatment of Pain Resulting From Chemotherapy Treatment

Inclusion Criteria: * If female, not of childbearing potential. * Patients with documented neuropathic pain * Cancer Patients who have completed a chemotherapy regimen which included taxanes or platinums (or both) and have no evidence actively progressive disease. Concurrent hormonal therapies are allowed * Patients with stable moderate to severe neuropathic pain * Patients with an Eastern Cooperative Oncology Group (ECOG) Performance Status score of 0 or 1. * Patients who are able to complete the study-related questionnaires independently in either English or Spanish. Exclusion Criteria: * History of peripheral neuropathy attributed to any cause other than chemotherapy. * Patients receiving any concurrent agents known to cause peripheral neuropathy within 30 days of Randomization. * Current use of other therapy (ies), including "alternative" therapies, for treatment of peripheral neuropathy within 30 days of Randomization (with the exception of protocol allowed concurrent medications). * Patients who used controlled release opioids within seven days of baseline period or who expect to use controlled release opioids at any time from baseline to end of study. * Patients with abnormal kidney function. * Patients with bone metastases. * Patients scheduled for treatment for their cancer with chemotherapy or radiotherapy between screening and the end of study visit. * Current use of lidocaine and other types of antiarrhythmic drugs within 30 days of Randomization. * Current use of scopolamine and acetylcholinesterase-inhibiting drugs such as physostigmine within 30 days of Randomization. * Current cause of Chemotherapy Induced Neuropathic Pain attributed to Velcade (Bortezomib) or vinca alkaloids or analogues such as vincristine, vinblasine, vinorelbine and vindesine. * Current use of tricyclic antidepressant medication, anticonvulsants and monoamine oxidase inhibitors. * Patients with current uncontrolled asthma or lung disease. * Patients with significant heart disease. * Use of an investigational agent within 30 days prior to screening or is scheduled to receive an investigational drug other than TTX during the course of the study. * Females who are pregnant or nursing