Niacinamide for the Treatment of Patients with Chronic Lymphocytic Leukemia with History of Non-melanoma Skin Cancer

Inclusion Criteria

• Male or female subject aged >= 18 years
• Confirmed diagnosis of CLL or small lymphocytic leukemia (SLL) patients per International Workshop on Chronic Lymphocytic Leukemia (iwCLL) 2018 criteria
• History of >= 1 non-melanoma skin cancer (NMSC) diagnosed within the last 5 years
• Total Bilirubin =< 1.5 x institutional upper limit of normal (ULN) * Subjects with a known diagnosis of Gilbert’s syndrome: direct bilirubin =< 1.5 x ULN
• Aspartate aminotransferase (AST) (serum glutamic oxaloacetic transaminase [SGOT])/alanine aminotransferase (ALT) (Serum Glutamic Pyruvic Transaminase [SGPT]) =< 3 x institutional ULN
• For female subjects: Negative pregnancy test or evidence of post-menopausal status. The post-menopausal status will be defined as having been amenorrheic for 12 months without an alternative medical cause. The following age-specific requirements apply: * Women < 50 years of age: ** Amenorrheic for >= 12 months following cessation of exogenous hormonal treatments; and ** Luteinizing hormone and follicle-stimulating hormone levels in the post-menopausal range for the institution; or ** Underwent surgical sterilization (bilateral oophorectomy or hysterectomy). * Women >= 50 years of age: ** Amenorrheic for 12 months or more following cessation of all exogenous hormonal treatments; or ** Had radiation-induced menopause with last menses > 1 year ago; or ** Had chemotherapy-induced menopause with last menses > 1 year ago; or ** Underwent surgical sterilization (bilateral oophorectomy, bilateral salpingectomy, or hysterectomy)
• Female subjects of childbearing potential and male subjects with a sexual partner of childbearing potential must agree to use a highly effective method of contraception

Exclusion Criteria

• Received cytotoxic chemotherapy (including fludarabine, cyclophosphamide, bendamustine, or chlorambucil) within the last 6 months
• Received allogeneic stem cell transplant within the last 6 months
• Taking nicotinamide or niacin supplements within the last 4 weeks
• Taken acitretin or other oral retinoids within the past 6 months
• Received field treatment for actinic keratosis (AKs) (topical use of 5-fluorouracil, imiquimod, diclofenac, retinoids; topical photodynamic therapy for AKs; laser resurfacing or chemical peel treatments for AKs) within the previous 4 weeks
• Large areas of confluent skin cancer at baseline preventing accurate assessment and counting of individual new skin cancers
• Need for ongoing carbamazepine use (possible interaction with nicotinamide)
• Severe gastrointestinal (GI) malabsorption that may interfere with absorption of nicotinamide (per investigator’s discretion)
• Patients with an expected life expectancy < 2 years
• Current evidence of uncontrolled, diabetes
• Current evidence or history of peptic ulcer disease
• Known human immunodeficiency virus (HIV) infection with a detectable viral load within 6 months of the anticipated start of treatment * Note: Subjects on effective antiretroviral therapy with an undetectable viral load within 6 months of the anticipated start of treatment are eligible for this trial
• Known active uncontrolled infection.
• Medical, psychiatric, cognitive, or other conditions that may compromise the subject's ability to understand the subject information, give informed consent, comply with the study protocol or complete the study
• Known prior severe hypersensitivity to investigational product (IP) or any component in its formulations (National Cancer Institute [NCI] Common Terminology Criteria for Adverse Events [CTCAE] version [v]5.0 grade >= 3)
• Subjects taking prohibited medications. A washout period of prohibited medications for a period of at least five half-lives or as clinically indicated should occur before the start of treatment
• Have ever received a solid organ transplant and are currently taking immunosuppressive medications