Effect of oral zinc regimens on human hepatic copper content: a randomized intervention study.

Zinc inhibits intestinal copper uptake, an effect utilized for treating Wilson's disease (WD). We used copper-64 (64Cu) PET/CT to examine how much four weeks of treatment with different zinc regimens reduced the hepatic 64Cu content after oral 64Cu administration and test if alternative regimens were noninferior to the standard regimen of zinc acetate 50 mg × 3 daily. Forty healthy persons were randomized to four different zinc protocols. The WD standard treatment zinc acetate 50 mg × 3 reduced the hepatic 64Cu content from 26.9 ± 7.5% to 13.3 ± 5.6% of the administered 64Cu. Zinc gluconate 50 mg × 3 was noninferior (P = 0.02) (35.8 ± 9.0% to 17.4 ± 7.5%). Zinc acetate 150 mg × 1 (33.1 ± 9.9% to 17.4 ± 7.5%) and zinc gluconate 150 mg × 1 (28.1 ± 6.7% to 22.0 ± 6.7%) were less effective. These effects were intra- and inter-individually highly variable, and 14% had no effect of any zinc regimen, which may explain disparities in zinc treatment efficacy in WD patients.