Effect of alipogene tiparvovec (aav1-lpls447x) on postprandial chylomicron metabolism in Lipoprotein lipase-deficient patients

Abstract

Background: Lipoprotein lipase-deficient (LPLD) individuals display marked chylomicronemia and hypertriglyceridemia associated with increased pancreatitis risk. The aim of this study was to determine the effect of im administration of an adeno-associated viral vector (AAV1) for expression of LPLS447X in muscle (alipogene tiparvovec, AAV1-LPLS447X) on postprandial chylomicron metabolism and on nonesterified fatty acid (NEFA) and glycerol metabolism in LPLD individuals. Methodology: In an open-label clinical trial (CT-AMT-011-02), LPLD subjects were administered alipogene tiparvovec at a dose of 1 × 1012 genome copies per kilogram. Two weeks before and 14 wk after administration, chylomicron metabolism and plasma palmitate and glycerol appearance rates were determined after ingestion of a low-fat meal containing 3H-palmitate, combined with (continuous) iv infusion of [U- 13C]palmitate and [1,1,2,3,3-2H]glycerol. Principal Findings: After administration of alipogene tiparvovec, the triglyceride (TG) content of the chylomicron fraction and the chylomicron-TG/total plasma TG ratio were reduced throughout the postprandial period. The postprandial peak chylomicron 3H level and chylomicron 3H area under the curve were greatly reduced (by 79 and 93%, 6 and 24 h after the test meal, respectively). There were no significant changes in plasma NEFA and glycerol appearance rates. Plasma glucose, insulin, and C-peptide also did not change. Conclusions/ Significance: Intramuscular administration of alipogene tiparvovec resulted in a significant improvement of postprandial chylomicron metabolism in LPLD patients, without inducing large postprandial NEFA spillover. Copyright © 2012 by The Endocrine Society.