Effects of NK-104, a new hydroxymethylglutaryl-coenzyme reductase inhibitor, on low-density lipoprotein cholesterol in heterozygous familial hypercholesterolemia

The clinical efficacy of NK-104, a novel and totally synthetic hydroxymethylglutaryl-coenzyme A reductase inhibitor, was assessed in 30 patients (men/women = 15/15, mean age 51 years) with heterozygous familial hypercholesterolemia. After a placebo phase of >4 weeks, NK-104 was given at an initial dose of 2 mg/day for 8 weeks, which was increased to 4 mg/day for a further 8 weeks. As a result of 2 mg/day of NK-104 treatment, mean ± SD of total and low-density lipoprotein cholesterol levels decreased significantly (p <0.0001) from baseline, namely from 8.80 ± 1.38 to 6.11 ± 1.09 mmol/L (−31%) and from 6.81 ± 1.52 to 4.09 ± 1.03 mmol/L (−40%), respectively. They decreased further (p <0.0001) as a result of 4-mg/day administration, to 5.52 ± 0.81 mmol/L (−37%) and 3.55 ± 0.85 mmol/L (−48%), respectively. Changes in high-density lipoprotein cholesterol levels failed to reach statistical significance. Serum triglyceride levels decreased significantly (p <0.0001) from baseline as a result of 4 mg/day of NK-104, from 1.99 ± 1.72 to 1.35 ± 0.90 mmol/L (−23%). Serum apolipoprotein B, CII, CIII, and E levels significantly decreased: mean changes from baseline at the end of the study were −41% (p <0.0001), −27% (p <0.0001), −19% (p = 0.002), and −37% (p <0.0001), respectively. On the other hand, apolipoprotein AI and AII levels significantly increased as a result of the treatment: +10% (p = 0.002) and +6% (p = 0.008), respectively. There were no adverse events observed in either clinical or laboratory findings that could be attributed to the treatment. These results suggest that the potency of NK-104 appears to be dose-dependent, and that NK-104 is safe and well tolerated in the treatment of patients with heterozygous familial hypercholesterolemia, and thus also provides a new therapeutic choice for subjects requiring lipid-modifying therapy.