Pilot Trial of Supplemental Vitamin A and Nicotinamide

The goal of this clinical trial is to assess the feasibility and safety of oral nicotinamide (NAM; a derivative of vitamin B3 [niacin]) and vitamin A in a high-risk population of kidney transplant recipients with a history of skin cancer to generate preliminary data for future cancer prevention clinical trials.

Inclusion Criteria:18 years old or greater;Either History of 2 or more histologically confirmed invasive cutaneous SCCs in the past 2 years orAt least one previously billed Healthcare Common Procedure Coding System code 17004 (destruction of 15 or more benign or premalignant lesions of the integumentary system);Understands, reads, and writes English proficiently.Exclusion Criteria:Liver disease;Active peptic ulcer disease;Recent myocardial infarction;Hypotension;Internal malignancy within past 5 years;Renal impairment with eGFR<15 mL/min/1.73 m2;Being unable for follow up due to social reasons;Gorlin's syndrome or other genetic skin cancer syndrome;Huge number of current skin cancers;Metastatic SCC or invasive melanoma within the past 5 years;Pregnancy or lactation;Need for ongoing carbamazepine use (which could have a possible interaction with NAM);Use of acitretin or other oral retinoids within the past 6 months;Use of supplemental NAM, niacin, vitamin A, or beta carotene within the past 6 months;Field treatment for actinic keratoses (AKs) within the previous 4 weeks;Use of topical steroids.