The plant–based enzyme Elelyso (taliglucerase alfa), developed by Protalix and Pfizer as an intravenous enzyme replacement therapy (ERT), is seen as effective and safe for the treatment of children with Type 1 Gaucher disease (GD), a literature review from 1995 to 2016 found.
Elelyso therapy in pediatric patients showed positive effects in growth, hemoglobin concentration, platelet counts, spleen and liver volumes, and levels of GD plasma biomarkers, according to the study.
The review, “Spotlight on taliglucerase alfa in the treatment of pediatric patients with type 1 Gaucher disease,” was published in the journal Pediatric Health, Medicine and Therapeutics.
GD is caused by a mutation in the gene that codes for the enzyme glucocerebrosidase, which results in the buildup of a type of fat called glucocerebroside in the liver, spleen, bone marrow, and nervous system. There are three types of GD. Patients with type 1 generally develop symptoms such as anemia, hepatosplenomegaly (an abnormally large liver and spleen), bone disease, delayed puberty, and growth retardation before the age of 20.
ERT is the recommended therapy for the treatment of GD for patients whose symptoms worsen. Early intervention with ERT, particularly in children, may help thwart the development of irreversible damage. Three types of ERTs are available for treatment of type 1 GD: Cerezyme (imiglucerase), produced in animal cells; VPRIV (velaglucerase alfa), produced in human cells; and Elelyso (taliglucerase alfa), which is plant–based.
Elelyso is the first FDA–approved plant–cell expressed recombinant therapeutic protein and is used in many countries for the treatment of adults with type 1 GD. It also is approved for pediatric patients in the U.S., Canada, and Australia.
This enzyme’s advantage is that it is produced with the appropriate modifications to allow the enzyme to enter macrophages, or immune system cells, to rectify fat accumulation. It also cannot be contaminated with mammalian pathogens because it doesn’t contain mammalian components.
Several clinical studies have been conducted on the use of Elelyso in children with type 1 GD. And three major clinical trials studied Elelyso’s safety and efficacy in pediatric patients. This review analyzes published data on the topic.
PB-06-002 (NCT00712348), a Phase 3, multicenter, switchover clinical trial, was conducted for nine months in patients who previously received Cerezyme. The patients were switched to Elelyso at a dose equivalent to their Cerezyme dose administered every two weeks.
PB-06-005 (NCT01132690), a Phase 3b, double-blind clinical trial, was conducted for 12 months in patients who had never been treated for the disease. The patients were administered either 30 or 60 U/kg of Elelyso every other week.
Finally, the multicenter extension study PB-06-006 (NCT01411228) was conducted to follow patients who previously were enrolled in and completed either the PB-06-002 or the PB-06-005 trials. In this study, patients received the same dose as in their original studies, but this time they were followed for a maximum of an additional 24 months.
In the PB-06-002/PB-06-006 study over 33 months, patients experienced a mean hemoglobin increase of 3.3%, a mean platelet count increase of 2.3%, a mean decrease in spleen volume of 5.3%, a mean decrease in liver volume of 8.8%, a decrease in chitotriosidase activity (a biomarker for GD) of 97.1%, and an increase in mean growth velocity of 2.5 cm per year.
In the PB-06-005/PB-06-006 study over 36 months, the 30 and 60 U/kg group showed an increase in mean hemoglobin concentration of 19.7% and 23.3%, respectively, an increase in mean platelet counts of 23.9% and 156.6%, a decrease in mean spleen volume of 67.8% and 68.9%, a decrease in liver volume of 37% and 34.3%, a decrease in chitotriosidase activity of 72.2% and 84.4%, and an increase in mean growth velocity of 5.5 and 6.7 cm per year.
Infusions of taliglucerase alfa were shown to have a positive safety profile with no severe adverse effects reported. While the number of patients may limit the findings, overall results conclude that taliglucerase alfa is both safe and effective in treating children with GD.