 The efficacy and safety of TRK-820 are to be evaluated in the treatment of intractable pruritus in patients with Chronic Liver Disease by administering 2.5, 5 and 10 microg of this drug or placebo for 28 days in four groups with a design of randomized, double-blind, parallel-group comparison. In addition, the plasma concentrations of TRK-820 and its primary metabolites are to be determined. 