NIAGEN and Persistent Chemotherapy-Induced Peripheral Neuropathy

Inclusion Criteria: * Be able to give written informed consent and HIPAA authorization * Be ≥ 18 and ≤ 85 years of age * Have received chemotherapy with taxane (e.g. paclitaxel, nab-paclitaxel, or docetaxol) or platinum-complex (e.g. oxaliplatin, carboplatin, or cisplatin) (alone or in combination) and completed therapy no sooner than 1 month and no later than 1 year earlier. * Have been treated with above compounds for head and neck cancer, small cell lung cancer, sarcoma, ovarian cancer, endometrial cancer, colorectal cancer, or breast cancer and been declared to have no visible evidence of disease. * Have an Eastern Cooperative Oncology Group (ECOG) Performance Status of 0-2 * Able to take medication orally - up to four capsules in the morning (am) and four capsules in the evening (pm). * Be determined to have a raw score of ≥ 12 on the sensory subscale or ≥ 11 on the motor subscale of the QLQ-CIPN20 questionnaire. * Females must be either postmenopausal for at least 1 year or surgically sterile for at least 6 weeks. Females of childbearing potential must have a negative pregnancy test at screening to be eligible for study participation and agree to take appropriate precautions to avoid pregnancy from screening through follow-up. * Males must agree to take appropriate precautions to avoid fathering a child from screening through follow-up. The following methods have been determined to be more than 99% effective (\<1% failure rate per year when used consistently and correc…