Clinical Trial: Extension of Study HGT-SAN-055 Evaluating Administration of rhHNS in Patients With Sanfilippo Syndrome Type A (MPS IIIA)

Study Status: Active, not recruiting
Recruit Status: Active, not recruiting
Study Type: Interventional

Official Title: An Open-Label Extension of Study HGT-SAN-055 Evaluating Long Term Safety and Clinical Outcomes of Intrathecal Administration of rhHNS in Patients With Sanfilippo Syndrome

Brief Summary:

Sanfilippo syndrome, or Mucopolysaccharidosis (MPS) III, is a rare lysosomal storage disease (LSD) caused by loss in activity of 1 of 9 enzymes necessary for degradation of the glycosaminoglycan (GAG) heparan sulfate (HS) in lysosomes. MPS IIIA results from deficiency of the enzyme heparan N-sulfatase (sulfamidase). In the absence of this enzyme, intermediates of the HS degradation process accumulate in the lysosomes of neurons and glial cells, with lesser accumulation outside the brain. MPS IIIA symptoms arise on average at 7 months of age, with the average age of diagnosis at 4.5 years for the majority of patients. Patients present a wide spectrum and severity of clinical symptoms. The central nervous system (CNS) is the most severely affected organ system in patients with MPS IIIA, evidenced by deficits in language development, motor skills, and intellectual development. In addition, there are abnormal behaviors including but not limited to aggression and excess motor activity/hyperactivity that contribute to disturbances in sleep.Overall, individuals with MPS IIIA have a marked developmental delay and significantly reduced lifespan to 15 years of age on average.

The purpose of this study is to collect long term safety and tolerability data in patients with MPS IIIA who previously received rhHNS in study HGT-SAN-055 (NCT01155778).


Detailed Summary:

No effective, disease-modifying therapies are currently approved as treatments for this devastating and disabling disease.

Shire Human Genetic Therapies (Shire HGT) is developing a sulfamidase enzyme replacement therapy (ERT)rhHNS for patients with MPS IIIA. rhHNS is being administered into the cerebrospinal fluid (CSF) via an surgically implanted intrathecal drug delivery device (IDDD), because when administered intravenously (IV) it does not cross the blood brain barrier (BBB).

This is a multicenter study designed to collect long-term safety and tolerability data in patients with Sanfilippo Syndrome Type A (MPS IIIA) who received rhHNS via a surgically implanted intrathecal drug delivery device (IDDD) in study HGT-SAN-055 and elected to continue therapy.Patients will continue in the treatment group as they participated in the HGT-SAN-055 study (rhHNS administered by IT injection 10 mg once per month, 45 mg once per month or 90 mg once per month.

The study duration will be a maximum duration of 8 years of rhHNS treatment or until rhHNS is commercially available, the patient discontinues from the study, the Sponsor stops the study, or the Sponsor discontinues the development of rhHNS.


Sponsor: Shire

Current Primary Outcome: Long-term safety [ Time Frame: 8 years ]

Safety will be measured by adverse events (by type and severity), changes in clinical laboratory testing (serum chemistry including liver function tests, hematology, and urinalysis), electrocardiograms (ECG), cerebrospinal fluid (CSF) chemistries (including cell counts and inflammatory markers), and anti-rhHNS antibodies (in CSF and serum).


Original Primary Outcome: Long-term safety [ Time Frame: Maximim of 4 years ]

Safety will be measured by adverse events (by type and severity), changes in clinical laboratory testing (serum chemistry including liver function tests, hematology, and urinalysis), electrocardiograms, cerebrospinal fluid (CSF) chemistries (including cell counts and inflammatory markers), and anti-rhHNS antibodies (in CSF and serum).


Current Secondary Outcome:

  • Standardized neurocognitive and behavioral assessments [ Time Frame: 8 years ]
    Sanfilippo-specific behavioral rating scales, gross and fine motor assessments, functional adaptive rating scales, quality of life questionnaires, and Children's Sleep Habits Rating Scale.
  • Concentration of rhHNS in cerebrospinal fluid (CSF) and serum [ Time Frame: 8 years ]
  • Concentration of inflammatory cytokines in serum and CSF [ Time Frame: 8 years ]
  • Concentration of safety and potential surrogate efficacy biomarkers in CSF, urine, and serum. [ Time Frame: 8 years ]
  • Concentration of heparan sulfate and heparan sulfate derivatives in urine, plasma and serum. [ Time Frame: 8 years ]
  • Brain magnetic resonance imaging (MRI) and auditory brainstem response (ABR), aka Brainstem Auditory Evoked Potentials. [ Time Frame: 8 years ]
    To assess patients regional brain volume and the extent of hearing loss.


Original Secondary Outcome:

  • Standardized neurocognitive and behavioral assessments [ Time Frame: Maximum of 4 years ]
    Sanfilippo-specific behavioral rating scales, gross and fine motor assessments, functional adaptive rating scales, quality of life questionnaires, and Children's Sleep Habits Rating Scale.
  • Concentration of rhHNS in cerebrospinal fluid (CSF) and serum [ Time Frame: Maximum of 4 years ]
  • Concentration of inflammatory cytokines in serum and CSF [ Time Frame: Maximim of 4 years ]
  • Concentration of safety and potential surrogate efficacy biomarkers in CSF, urine, and serum. [ Time Frame: Maximum of 4 years ]
  • Concentration of heparan sulfate and heparan sulfate derivatives in urine and CSF. [ Time Frame: Maximim of 4 years ]
  • Brain magnetic resonance imaging (MRI) and auditory brainstem response (ABR), aka Brainstem Auditory Evoked Potentials. [ Time Frame: Maximum of 4 years ]
    To assess patients regional brain volume and the extent of hearing loss.


Information By: Shire

Dates:
Date Received: February 16, 2011
Date Started: February 2011
Date Completion: October 2021
Last Updated: May 31, 2016
Last Verified: May 2016