Extension Study of Protocol ENB-006-09 - Study of Asfotase Alfa in Children With Hypophosphatasia (HPP)

Phase 2

Completed

Brief Summary: This clinical trial studies the long term safety and efficacy of asfotase alfa in children with HPP who completed Study ENB-006-09 (NCT00952484).

Detailed Description: 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 limited data available on the natural course of this disease over time, particularly in patients with the juvenile-onset form.

Recruitment & Eligibility

Inclusion Criteria

Compliant and satisfactory completion of Enobia-sponsored clinical trial ENB-006-09
Written informed consent by parent or other legal guardian prior to any study procedures being performed
Parent or other legal guardian willing to comply with study requirements

Exclusion Criteria

Clinically significant disease that precludes study participation, in the Investigator's opinion
Treatment with an investigational drug other than asfotase alfa
Enrollment in any study (other than ENB-006-09) involving an investigational drug, device, or treatment for HPP
Prior treatment with bisphosphonates

Primary Outcome Measures

Name	Time	Method
Skeletal Radiograph Evaluation Using a Qualitative Radiographic Global Impression of Change (RGI-C) Scale Compared to Baseline (Pre-treatment) in Study ENB-006-09.	At least 72 months of treatment with asfotase alfa	Evaluation of radiographic change in rickets severity (as assessed by skeletal radiographs of the hands/wrists and knees) from the Baseline of Study ENB-006-09 (NCT00952484) to the End of Study (EOS) visit in Study ENB-008-10 using an ordinal RGI-C scale score. The RGI-C is a 7-point rating scale that ranges from -3 (indicative of severe worsening of HPP associated rickets) to +3 (indicative of complete or near complete healing of HPP associated rickets). The time points will be pre-treatment (Baseline from Study ENB-006-09) to the last radiographic assessment in Study ENB-008-10, which represents at least 72 months of treatment.

Secondary Outcome Measures

Name	Time	Method

Locations (2): Shriners Hospital for Children
🇺🇸
Saint Louis, Missouri, United States
Children's Hospital Health Sciences Centre
🇨🇦
Winnipeg, Manitoba, Canada
Shriners Hospital for Children
🇺🇸Saint Louis, Missouri, United States