Effects of acipimox on serum lipids, lipoproteins and lipolytic enzymes in hypertriglyceridemia

Two separate studies were carried out with acipimox, a new antilipolytic agent with long-lasting activity. First, in a randomized, double-blind, cross-over study a dose of 750 mg/day of acipimox versus placebo was employed for 60 days in 11 patients with type IV hyperlipoproteinemia. Mean plasma triglyceride levels were reduced after acipimox compared to placebo (434 +/- 60 vs 777 +/- 224 mg/dl, P less than 0.01). Serum total cholesterol fell also significantly after acipimox compared to placebo. No significant alteration was observed in the HDL2/HDL3 ratio or in the concentration or composition of the HDL subfractions. Six patients with severe hypertriglyceridemia (2 type IV and 4 type V) and low lipoprotein lipase (LPL) activity took part in a second, open study, lasting for 9 months. Acipimox was given at a dose of 750 mg/day for the first 6 months and 1200 mg/day for the last period. The response of serum total and VLDL triglycerides was inconsistent. HDL cholesterol was significantly raised (+33.3%) after 9 months of treatment due to changes of HDL2 and HDL3 cholesterol, phospholipid and protein concentrations. LPL activity was markedly reduced in adipose tissue at 9 months. No significant changes occurred in postheparin plasma LPL activity. In contrast, hepatic lipase activity showed a reduction of about 25% from 6 months of treatment onwards.