Safety, Tolerability, Ascending Dose and Dose Frequency Study of rhHNS Via an IDDD in MPS IIIA Patients

Summary

Sanfilippo syndrome, or Mucopolysaccharidosis (MPS) III, is a rare lysosomal storage disease (LSD) caused by loss in activity of 1 of 4 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). 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. 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 of 15 years of age on average. The purpose of this study is to determine the safety and tolerability of rhHNS via ascending doses administered via an a surgically implanted intrathecal drug delivery device (IDDD) intrathecal (IT) route once monthly (or every two weeks) for 6 months in patients with MPS IIIA.

Timeline

Start

2010-06-01

Primary completion

2012-09-01

Completion

2012-09-01

Publications

• Jones SA, Breen C, Heap F, Rust S, de Ruijter J, Tump E, Marchal JP, Pan L, Qiu Y, Chung JK, Nair N, Haslett PAJ, Barbier AJ, Wijburg FA. A phase 1/2 study of intrathecal heparan-N-sulfatase in patients with mucopolysaccharidosis IIIA. Mol Genet Metab. 2016 Jul;118(3):198-205. doi: 10.1016/j.ymgme.2016.05.006. Epub 2016 May 10.
• King B, Marshall N, Beard H, Hassiotis S, Trim PJ, Snel MF, Rozaklis T, Jolly RD, Hopwood JJ, Hemsley KM. Evaluation of enzyme dose and dose-frequency in ameliorating substrate accumulation in MPS IIIA Huntaway dog brain. J Inherit Metab Dis. 2015 Mar;38(2):341-50. doi: 10.1007/s10545-014-9790-8. Epub 2014 Nov 25.
• Langford-Smith A, Wilkinson FL, Langford-Smith KJ, Holley RJ, Sergijenko A, Howe SJ, Bennett WR, Jones SA, Wraith J, Merry CL, Wynn RF, Bigger BW. Hematopoietic stem cell and gene therapy corrects primary neuropathology and behavior in mucopolysaccharidosis IIIA mice. Mol Ther. 2012 Aug;20(8):1610-21. doi: 10.1038/mt.2012.82. Epub 2012 May 1.

Drugs

Indications