Combining oral Zavesca (miglustat) with intravenous enzyme replacement therapy (ERT) may prevent neurological problems in patients with neuronopathic Gaucher disease, a case study suggests.
The research, “Combination Therapy In A Patient With Chronic Neuronopathic Gaucher Disease: A Case Report,” was published in the Journal of Medical Case Reports.
At the moment there are two ways to treat Gaucher. One is intravenous ERT, which involves patients receiving copies of the functional acid β-glucosidase. The other is oral substrate reduction therapy, which involves them receiving a substance that prevents the accumulation of the toxin glucosylceramide.
Patients with type 2 and 3 Gaucher experience neurological problems. These types, collectively known as neuronopathic Gaucher, fail to respond to intravenous ERT. That’s because glucocerebrosidase is unable to cross the blood-brain barrier, which protects the brain by determining which molecules can reach it and which can’t.
Substrate-reduction-therapy agents can cross the membrane. That suggests that a combination of the therapies could be a good way to treat the neurological symptoms of Gaucher.
Researchers took a close look at the case of a 7-year-old boy with neuronopathic Gaucher who had L444P mutations in his GBA gene.
He had been treated with ERT since he was 18 months old. When he was 2 1/2, his doctors combined the ERT with the substrate-reduction-therapy Zavesca. They first decided on a dose of Zavesca they believed was appropriate for his size.
Doctors gave the boy a third of the dose each day during the first two weeks of treatment, and two-thirds of a dose a day in the next two weeks. After that, they changed the dose to 100 mg three times a day.
To ensure the boy’s gastrointestinal system could tolerate Zavesca, his doctors prescribed a diet that limited his consumption of enriched carbohydrates, such as sucrose and maltose. The patient had mild diarrhea after starting Zavesca, but it became less frequent over time.
The combined treatment improved the size of the patient’s spleen, an organ important to blood and immune-system functioning. It also normalized his blood values and the activity of his plasma angiotensin-converting enzyme (ACE), which helps to control blood pressure.
Five years after receiving the combination therapy, he showed no signs of neurological problems.
“This case supports the concept that the addition of oral [Zavesca] to ongoing intravenous ERT may help prevent neurological deterioration in patients with chronic [neuropathic Gaucher disease]”, researchers concluded. “The importance of dietary modifications has also been confirmed. Further follow-up studies are needed to better define the therapeutic effect of combined treatment in this [Gaucher-disease] subtype.”