What is hunter syndrome or MPS-II?
Hunter syndrome is one of several related lysosomal storage diseases or otherwise known as MPS conditions. In Hunter syndrome, GAG builds up in cells throughout the body due to a deficiency or absence of the vital enzyme iduronate-2-sulfatase (I2S) due to genetic malfunction. For people without this condition they have the vital enzyme which is used to take waste away from the body. However in hunter syndrome patients this enzyme is missing which then leads to several horrible symptoms. These symptoms include but not limited to severe deafness, joint stiffness, organ failure and sleep apnea which ultimately leads to an early death, normally in the second decade of life. In addition to this some patients also experience brain impairments.
Is there a cure for hunter syndrome or MPS-II?
There is presently no cure for hunter syndrome but there is a treatment called Elaprase.
Elaprase provides the body with the vital enzyme which it is missing.
How does Elaprase helps someone with MPS-II?
Elaprase is a life saver; it stabilizes the body and provides the body with this vital enzyme. Patients accessing Elaprase have the opportunity to live a life free of unnecessary pain and suffering
How is Elaprase administered?
Elaprase is a weekly infusion and is administered intravenously. Most MPS-II patients have a port-a-cath and this avoids trying to find a vein each week. Each week the “port” is accessed via a needle which then allows the medicine to be transferred intravenously.
Is Elaprase available to patients in all countries?
Elaprase is available in approximately 25 countries around the world. Unfortunately not all patients can access Elaprase treatment. Countries such as Australia has discriminatory criteria that refuses access to patients if they central nervous system (CNS) involvement.
Is there any way to treat the brain effects of MPS-II?
Elaprase is an given intravenously therefore it does not cross the blood brain barrier. GAG's are built up and stored in the brain which leads to severe brain impairment for some sufferers. However, currently there are devloping medical breakthroughs i.e. Intrathecal clinical trials been conducted in the United Sates and the United Kingdom with very positive results
What are Intrathecal clinical trials?
Elaprase administered Intrathecally is being clinically trialed in the USA and the UK to treat patients with CNS involvement. Elaprase is being administered in the spinal cord so that it reaches the brain. Trials have been ongoing for the last two-three years and so far no patients have been reported to be adversely affected by this clinical trial. Studies are still ongoing so there is very little published data but early results are very positive from parents of patients. Intrathecal enzyme replacement is proving to be an effective way to treat the effects of MPS-II in the brain.
How safe is Intrathecal clinical trials?
Phase I/II clinical had expected to enroll 16 patients with MPS II between the ages of 3 to 8 years with evidence of early neurocognitive decline using an open-label, three-dose trial design. The monthly intrathecal administration of idursulfase-IT was given using a Port-A-Cath® II Low Profile™ intrathecal implantable access system manufactured by Smiths Medical MD, Inc. (St. Paul, MN) that requires surgical Ref: implantation.https://www.mpssociety.org/clinical-trials/
Trials were conducted in the United States and later extended to the UK. These studies were ongoing but from speaking with moms that have had children participating in phase I/II of the clinical trials there had been no major medical issues. During stages of the trials there were some issues with some of the Port-A-Cath devices that was been used to deliver ERT through the spinal cord. I believe those issues was been rectified.
As these are clinical studies there are going to be a few minor and sometimes major hiccups along the way. But Shire has been working to finetune their devices and protocols.
I personally believe the benefits out weight the challenges because there is no going back with hunter syndrome once a child’s brain began to deteriorate it will only get worse. (Personal experience, three brothers with MPS-II)
As I have been informed by Shire, phase II/III is expected to commence fairly soon and they are committed to offering every patient the best care possible.