Clinical Trial: Duration of Effect of Alipogene Tiparvovec Treatment, Which Was Administered in Other Studies

Study Status: Terminated
Recruit Status: Terminated
Study Type: Observational

Official Title: Prospective, Non-interventional, Non-randomised, Open-label, Adult Study to Assess the Long Term Biological Therapeutic Response to Alipogene Tiparvovec in Lipoprotein Lipase Def

Brief Summary:

LPL (Lipoprotein Lipase) is an enzyme which plays an important role in the elimination of triglycerides (fat) and the clearance of dietary fat particles known as chylomicrons (CM) in the blood. In patients who have an abnormal LPL gene, the enzyme does not work (total, hereditary LPL deficiency), which results in a large increase in the amount of triglycerides (fats) and chylomicrons in the blood. This increases the risk of inflammation in the pancreas and leads to long term negative effects for bloods vessels (atherosclerosis). Current medications and / or a strict and low fat diet do not sufficiently reduce the level of triglycerides in order to prevent these conditions. To solve this problem, the company, AMT is developing a gene therapy (AMT-011).

In normal healthy individuals, fat particles are rapidly cleared from the circulation following a standard meal. Within approximately 3 hours the highest levels of fat is reached and clearance is achieved within the subsequent 9 hours. In LPLD subjects, the clearance of fat is greatly reduced as a direct consequence of the lack of LPL. During this study, a standard meal with a tracer (3H-palmitate) is given. Since palmitate is incorporated in the dietary fat, this study enabled monitoring of appearance of newly formed dietary fat into- and clearance of these newly formed dietary fats from the circulation, over time.

The principal aim of the study is to verify if the gene therapy (AMT 011) is still effective in the treatment of this condition. Systemic appearance and clearance of new formed dietary fat particles after ingestion of the meal will be determined by measuring the level of tracer at different time points.


Detailed Summary:

Lipoprotein lipase deficiency (LPLD) is a rare autosomal recessive inherited disorder caused by loss-of-function mutations in the lipoprotein lipase (LPL) gene. It is the most common genetic cause of hyperchylomicronaemia, a condition which results in continuous and excessively high levels of plasma chylomicrons (CM) and severe hypertriglyceridaemia. Lipoprotein lipase normally mediates the hydrolysis of triglycerides (TG) in CMs and very low-density lipoproteins (VLDL) and thereby aids in the clearance of TG-rich lipoproteins and reduction of TGs in the circulation.

Alipogene tiparvovec (Glybera®) is in development for the therapy of LPLD. In summary, alipogene tiparvovec contains the human lipoprotein (LPL) gene variant LPLS447X in a non-replicating vector in solution administered in a one-time series of intramuscular injections in the arms/legs.The aim of alipogene tiparvovec (Glybera®) administration is to provide LPL activity and to stimulate CM metabolism in LPLD patients.

To test the activity of LPL in subjects previously treated with alipogene tiparvovec in this study LPLD subjects will be given a radiolabeled meal supplemented with a labeled tracer, 3H-palmitate. Since dietary palmitate is incorporated into CMs as they are formed in the enterocytes of the gut, this enables monitoring of the appearance and subsequent clearance of newly formed CMs from the circulation over time, the so-called "postprandial test". The radiolabeled meal will be provided in a liquid form similar to a milkshake. After ingestion of the radiolabeled meal, level of radiolabel in the CM fraction at different time points prior to and during the postprandial phase will be measured and thus determine the appearance and clearance of CMs within the circulation.

The principal a
Sponsor: Amsterdam Molecular Therapeutics

Current Primary Outcome: Composite of Pharmacodynamics [ Time Frame: pre dose, 0, 1, 2, 3, 4, 5, 6, 7, 8, 9, 12, 24 hours post dose ]

Peak level, time-to-peak, and area under the curve (AUC) for tracer in plasma and chylomicron (CM) fraction to assess metabolism of newly-formed CMs in LPLD subjects previously treated with alipogene tiparvovec and to compare with untreated LPLD subjects and healthy controls.


Original Primary Outcome: Same as current

Current Secondary Outcome:

  • Triglyceride (TG)-rich lipoproteins [ Time Frame: pre dose, 0, 1, 2, 3, 4, 4, 6, 7, 8, 9, 12, 24 hours post dose ]
    Surface and core components of TG-rich lipoproteins (TG, TChol, apoB100, and apoB48)in plasma and in the CM fraction will be measured.
  • Glucose [ Time Frame: pre dose, 0, 2, 3, 4, 5, 6, 7, 8, 9, 12, 24 hours post dose ]
    The levels of glucose in plasma.
  • Adverse Events (AE) [ Time Frame: Up to 21 days. Serious AEs will be followed to their resolution. ]
    Monitoring general state of health of subjects and to assess the safety of ingestion of a radiolabeled meal, containing the radiolabel 3H palmitate through review of the incidence and severity of adverse events (AEs).
  • Laboratory tests [ Time Frame: Up to 21 days ]
    Monitoring general state of health in LPLD subjects previously treated with alipogene tiparvovec compared to untreated LPLD subjects and healthy volunteers through review of laboratory findings (haematology, clinical chemistry, and urinalysis).
  • Vital signs [ Time Frame: Up to 21 days ]
    To monitor the general state of health in LPLD subjects previously treated with alipogene tiparvovec compared to untreated LPLD subjects and healthy volunteers through review of the vital signs.
  • Physical examination [ Time Frame: Up to 21 days ]
    To monitor the general state of health in LPLD subjects previously treated with alipogene tiparvovec compared to untreated LPLD subjects and healthy volunteers through review of physical examination findings.
  • ECG [ Time Frame: Up to 21 days ]
    To monitor the general state of health in LPLD subjects previously treated with alipogene tiparvovec compared to untreated LPLD subjects and healthy volunteers through review of 12-lead electrocardiograms (ECGs).
  • C-peptide [ Time Frame: pre dose, 0, 1, 2, 3, 4, 5, 6, 7, 8, 9, 12, 24 post dose ]
    Levels of C-peptide in plasma
  • Non Esterified Fatty Acids (NEFA) [ Time Frame: pre dose, 0, 1, 2, 3, 4, 5, 6, 7, 8, 9, 12, 24 post dose ]
    Levels of NEFA in plasma will be measured


Original Secondary Outcome: Same as current

Information By: Amsterdam Molecular Therapeutics

Dates:
Date Received: September 28, 2011
Date Started: September 2011
Date Completion:
Last Updated: March 27, 2015
Last Verified: March 2015