Amsterdam Molecular Therapeutics, a company involved in the field of human gene therapy, has results from a long-term efficacy study of Glybera (alipogene tiparvovec) that showed improved chylomicron metabolism could be used as a biomarker for increased lipoprotein lipase (LPL) activity in those patients missing the gene that produces this protein. Glybera is a gene therapy product under development for the treatment of lipoprotein lipase deficiency (LPLD) that is currently under review for marketing approval with the EMA.

A total of 5 LPLD patients were administered Glybera (1x1012 genome copies/kg, IM). At weeks 14 and 52 post-administration, patients were given a test meal with a tracer molecule designed to monitor the breakdown of newly formed chylomicrons in the blood. Prior to therapy, all patients exhibited poor post-meal chylomicron handling as measured by amount seen in the plasma over 9 hours following meal ingestion. After treatment with Glybera, the amount of tracer found was greatly reduced and in each case was completely eliminated within nine hours. The effect was consistent in all patients and sustained as observed at both the 14 and 52 week time points.