Hunter Syndrome Study

This observational study was evaluating the effect of anti-idursulfase immunoglobulin antibodies on idursulfase safety (measured by infusion-related adverse events), between patients who developed anti-idursulfase antibodies and those patients who do not, after long term idursulfase enzyme replacement therapy. The study was also evaluating the effect of anti-idursulfase antibodies on idursulfase efficacy, measured by urine glycosaminoglycan (GAG) levels between patients who develop anti-idusulfase antibodies and those patients who do not.

Hunter syndrome is an inherited disease, mostly affecting young males, in which long chains of sugar molecules are not broken down in the correct way, and therefore build up in the body and cause damage. The condition is caused by a lack of the enzyme iduronate sulfatase. Symptoms include aggressive behavior, hyperactivity, mental retardation and spasticity. Treatment usually includes intravenous idursulfase or bone marrow transplantation.

The study aimed to enroll 100 male patients across the UK, US and Brazil. Illingworth Research performed all UK monitoring activities for the study, with Research Nurses providing site-support and assisting with data entry activities.