The essential trace element zinc maintains liver functions. Liver diseases can alter overall zinc concentrations, and hypozincemia is associated with various hepatic pathologies. Modulating systemic zinc through dietary supplementation is potentially useful for liver diseases. We evaluated the usefulness of zinc (NPC-02; acetate formulation) supplementation. We conducted two NPC-02 studies on zinc-deficient patients (serum zinc < 70 μg/dL). Study 1: double-blind, randomized, placebo-controlled trial on 57 subjects with chronic liver diseases comparing serum zinc in patients given NPC-02 (NPC-02 group) versus placebo (Placebo group). Study 2: dose adjustment study on 43 subjects with/without liver diseases to determine proportions maintaining serum zinc target (≥ 80 μg/dL but < 200 μg/dL). In study 1, NPC-02 subjects had higher serum zinc concentrations at week 8 than Placebo subjects (83.2 ± 20.2 and 61.3 ± 12.0, respectively; P < 0.0001), and more NPC-02 than Placebo subjects achieved the serum zinc target (15/27 vs. 1/26). In study 2, the NPC-02-induced serum zinc increase was dose-dependent in subjects both with and without liver diseases (r = 0.5143, P = 0.0022 and r = 0.5753, P = 0.0005, respectively). Interestingly, there was a marginally positive correlation between serum zinc and albumin levels in subjects with but not in those without liver diseases (r = 0.4028, P = 0.0631 and r = 0.1360, P = 0.5567, respectively). NPC-02 dose-dependently increases serum zinc in hypozincemic patients, regardless of liver disease. NPC-02 is a potentially effective therapy for liver cirrhosis, in which zinc deficiency is common. Clinical trial registry number: NCT02337569, NCT02321865.
Keywords: Chronic liver disease; Dose adjustment; Hypozincemia; NPC-02; Serum zinc concentration; Zinc deficiency.