Phytocannabinoids for the Treatment of Chronic Chemotherapy-Induced Peripheral Neuropathy in Breast and Colon Cancer Survivors

Inclusion Criteria: Documented informed consent of the participant and/or legally authorized representative Assent, when appropriate, will be obtained per institutional guidelines Agreement to allow the use of archival tissue from diagnostic tumor biopsies If unavailable, exceptions may be granted with study principal investigator (PI) approval Willingness to comply with all study interventions including the use of medical cannabis and follow-up assessments Age: >= 18 years Eastern Cooperative Oncology Group (ECOG) =< 2 Ability to read and understand English for questionnaires Patients must have either neuropathy >= 1 according to Common Terminology Criteria for Adverse Events (CTCAE) version (v) 5.0 scale or a neuropathy score of > 3 on a 0-10 scale plus a FACT/GOG-Ntx score of > 10 The patient's previous chemotherapy treatment must have included a taxane (paclitaxel, nab-paclitaxel, or docetaxel) or platinum (cisplatin, oxaliplatin, or carboplatin) and considered the primary cause of the neuropathy by the medical team Total bilirubin =< 1.5 x upper limit of normal (ULN) (unless has Gilbert's disease) Aspartate aminotransferase (AST) =< 3 x ULN Alanine aminotransferase (ALT) =< 3 x ULN Women of childbearing potential (WOCBP): negative urine or serum pregnancy test. If the urine test is positive or cannot be confirmed as negative, a serum pregnancy test will be required Agreement by females and males of childbearing potential to use an effective method of birth control or abstain from heterosexual activity for the course of the study through at least 1 months after the last dose of protocol therapy Childbearing potential defined as not being surgically sterilized (men and women) or have not been free from menses for > 1 year (women only) Current active treatment with chemotherapy, radiation or surgery in the past 3 months or planned treatment during this study protocol period. Note: Hormonal therapy is allowed Exclusion Criteria: Concurrent use of other alternative medicines such as medical cannabis, herbal agents and high dose vitamins and minerals Liver cirrhosis Child-Pugh B or C Mental incapacitation or significant emotional or psychological disorder that, in the opinion of the investigators, precludes study entry (These patients may not be able to cooperate with this slightly invasive procedure or with the data collection process) History of diabetic neuropathy, neuropathy related to human immunodeficiency virus (HIV), or other medical causes of chronic neuropathy in the baseline assessment including past medical history, any history of diabetes, alcoholism, and vitamin B deficiency Previous medical cannabis use for any indication within 30 days of enrollment Planned or actual changes in type of medications that could affect symptoms related to CIPN. New medications for the treatment of CIPN are not allowed during the study. Note: Subjects need to be on stable doses of CIPN medications for 4 weeks Strong inhibitors or inducers of CYP3A4 History of allergic reactions attributed to compounds of similar chemical or biologic composition to study agent Clinically significant uncontrolled illness Diagnosis of Gilbert's disease Females only: Pregnant or breastfeeding Any other condition that would, in the Investigator's judgment, contraindicate the patient's participation in the clinical study due to safety concerns with clinical study procedures Prospective participants who, in the opinion of the investigator, may not be able to comply with all study procedures (including compliance issues related to feasibility/logistics)