This is a randomized, double-blind, placebo-controlled, stepwise study of escalating doses of Basis (NR/pterostilbene) in patients with AKI. The study will potentially comprise up to four Steps. The purpose of the stepwise approach is to identify the dose of Basis that achieves at least a 50% and up to 100% increase in white blood cell (WBC) content of nicotinamide adenine dinucleotide (NAD+) without side-effects.