Abstract 682: Lapaqistat Acetate Monotherapy: Effects of a Novel Squalene Synthase Inhibitor on LDL-C Levels and Other Lipid Parameters in Patients with Primary Hypercholesterolemia
Background: Lapaquistat acetate (LAPA) inhibits squalene synthase, an important enzyme in the cholesterol biosynthetic pathway. Early studies showed that LAPA reduced LDL-C and improved lipid profiles in animals and humans.
Methods: This multicenter, phase III, randomized, double-blind, parallel-group, placebo-controlled study assessed LAPA monotherapy in nondiabetic patients ≥ 18 yrs old with primary hypercholesterolemia (mean LDL-C > 130 mg/dL and < 220 mg/dL; mean triglyceride [TG] ≤400 mg/dL). Treatment-naïve patients or patients discontinuing previous lipid-lowering therapy underwent a 6-wk dietary stabilization period, then were randomized to 100 mg LAPA (n = 241) or Placebo (n = 120) once daily for 12 wks. The primary endpoint was percent (%) change from baseline compared with Placebo in direct LDL-C at Wk 12 or last on-treatment value. Secondary endpoints included: % change in calculated LDL-C, non-HDL-C, total cholesterol (TC), Apo B, HDL-C, VLDL-C, Apo A1, TG, and hs-CRP. Safety was monitored using clinical and laboratory examinations.
Results: LAPA significantly reduced LDL-C levels (see Table⇓) within 2– 4 wks of treatment initiation that were maintained throughout the study. LDL-C remained relatively unchanged in the Placebo group. Compared with Placebo, LAPA lowered LDL-C levels 20.09% by end of study (p < 0.001). Non-HDL-C, TC, Apo B, VLDL-C, Apo A1, TG, and hs-CRP were also significantly reduced vs Placebo. Both the overall adverse event (AE) profile and the rate of AEs considered potentially related to study drug (~24%), were similar between treatment groups. Two serious AEs occurred in each group; the 2 SAEs in lapaquistat-treated patients were considered not related to study drug.
Conclusion: LAPA (100 mg/day) monotherapy provided significant improvements in LDL-C, non-HDL-C, TC, Apo B, VLDL-C, TG, and hs-CRP levels, was generally safe and well tolerated, and potentially represents a novel treatment for hypercholesterolemic patients.