Clinical Trial: Extension Study of Protocol ENB-002-08 - Study of Asfotase Alfa in Infants and Young Children With Hypophosphatasia (HPP)

Study Status: Completed
Recruit Status: Completed
Study Type: Interventional

Official Title: Extension Study of ENB-0040 (Human Recombinant Tissue Nonspecific Alkaline Phosphatase Fusion Protein) in Severely Affected Infants and Young Children With Hypophosphatasia

Brief Summary:

This clinical trial studies the long term safety and efficacy of asfotase alfa in infants and young children with infantile onset HPP who completed the ENB-002-08 study.

Partial funding for this study was provided by the Office of Orphan Product Development (OOPD).


Detailed Summary:

Asfotase Alfa was formerly referred to as ENB-0040

Hypophosphatasia (HPP) is a life-threatening, genetic, and ultra-rare metabolic disease characterized by defective bone mineralization and impaired phosphate and calcium regulation that can lead to progressive damage to multiple vital organs, including destruction and deformity of bones, profound muscle weakness, seizures, impaired renal function, and respiratory failure. There are no approved disease-modifying treatments for patients with this disease. There is also limited data available on the natural course of this disease over time, particularly in patients with the juvenile-onset form.


Sponsor: Alexion Pharma GmbH

Current Primary Outcome:

  • To determine the long-term tolerability of subcutaneous (SC) asfotase alfa [ Time Frame: 84 months ]
    The time points will be pre-dose (Baseline from the ENB-002-08 study) to Month 84 of the ENB-003-08 study which represents 90 months.
  • To assess the long-term efficacy of asfotase alfa in treating rickets in infants and young children with HPP [ Time Frame: 84 Months ]
    The time points will be pre-dose (Baseline from ENB-002-08 study) to Month 84 of the ENB-003-08 study which represents 90 months.


Original Primary Outcome: Skeletal radiograph using a qualitative Radiographic Global Impression of Change (RGI-C) scale [ Time Frame: 24 months ]

The time points will be pre-treatment (Baseline from the 002 study) to Month 24 of the 003 study which represents 30 months of treatment.


Current Secondary Outcome:

  • To assess the long-term pharmacodynamics (PD) of SC asfotase alfa [ Time Frame: 84 Months ]
    The time points will be pre-dose (baseline from the ENB-002-08 study) to Month 84 of the ENB-003-08 study whih represents 90 months.
  • To assess the effect of SC asfotase alfa on growth and development [ Time Frame: 84 Months ]
    The time points will be pre-dose (Baseline from the ENB-002-08 study) to Month 84 in the ENB-003-08 study which represents 90 months.
  • To assess the effect of SC asfotase alfa on survival, respiratory function, and other clinical signs and symptoms of HPP in infants and young children [ Time Frame: 84 Months ]
    The time points will be pre-dose (Baseline from the ENB-002-08 study) to Month 84 of the ENB-003-08 study which represents 90 months.


Original Secondary Outcome: Pharmacokinetics (PK) using serum PK and trough levels and pharmacodynamics (PD) of plasma inorganic pyrophosphate (PPi), pyridoxal 5'-phosphate (PLP) and serum parathyroid hormone (PTH) as biomarkers for hypophosphatasia (HPP) [ Time Frame: 24 months ]

Information By: Alexion Pharma GmbH

Dates:
Date Received: September 17, 2010
Date Started: April 2009
Date Completion:
Last Updated: September 27, 2016
Last Verified: September 2016