Safety and Efficacy Study of Asfotase Alfa in Adolescents and Adults With Hypophosphatasia (HPP)
- Registration Number
- NCT01163149
- Lead Sponsor
- Alexion Pharmaceuticals, Inc.
- Brief Summary
This clinical trial was conducted to study hypophosphatasia (HPP), a bone disorder caused by gene mutations or changes. These gene mutations cause low levels of an enzyme needed to harden bone. The purpose of this study was to test the safety and efficacy of two doses of the study drug called asfotase alfa as compared to a control group to see effects on adolescents and adults with HPP.
- 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
- Status
- COMPLETED
- Sex
- All
- Target Recruitment
- 19
Not provided
Not provided
Study & Design
- Study Type
- INTERVENTIONAL
- Study Design
- PARALLEL
- Arm && Interventions
Group Intervention Description Cohort 1 asfotase alfa Cohort 1: Daily SC injections of 0.3 mg/kg asfotase alfa (2.1 mg/kg/week total) Cohort 2 asfotase alfa Cohort 2: Daily SC injections of 0.5 mg/kg asfotase alfa (3.5 mg/kg/week total)
- Primary Outcome Measures
Name Time Method Change From Baseline to Week 24 for Plasma Pyridoxal-5' Phosphate (PLP) Baseline, Week 24 Blood samples were collected to evaluate the effect of asfotase alfa on reduction in plasma pyridoxal-5' phosphate (PLP)
Safety and Tolerability of Asfotase Alfa Up to 288 weeks exposure to asfotase alfa The safety and tolerability of daily subcutaneous (SC) injections of asfotase alfa was assessed by routine monitoring of patients for treatment-emergent adverse events (TEAEs) and injection-associated reactions (IARs).
Change From Baseline to Week 24 for Plasma Inorganic Pyrophosphate (PPi) Baseline, Week 24 Blood samples were collected to evaluate the effect of asfotase alfa on reduction in plasma inorganic pyrophosphate (PPi)
- Secondary Outcome Measures
Name Time Method Change From Baseline in HPP-related Osteomalacia as Measured by Trans-iliac Crest Bone Biopsy: Osteoid Thickness Baseline, Week 24 (Control group), and Week 48 (Asfotase alfa groups). A trans-iliac crest bone biopsy was performed to quantify changes from Baseline in histomorphometric parameters relevant for evaluation of osteomalacia severity, including Osteoid Thickness (um). The difference in time under observation between asfotase alfa groups (Week 48) and control group (Week 24) resulted from study design, ie, control subjects transitioned to active treatment after the Week 24 visit.
Change in Walking Ability as Measured by the Six-Minute Walk Test (6MWT) Baseline, Week 24 (primary treatment period) and up to 288 weeks of asfotase alfa exposure The patient was instructed to walk the length of a pre-measured hallway for 6 minutes. The primary measurement was distance walked (in meters).
Change From Baseline in Bone Mineral Content (BMC) as Measured by Dual-energy X-ray Absorptiometry (DXA) Baseline, every 24 weeks through Week 96, then every 48 weeks until Week 288. A DXA scan was performed to evaluate bone mineral content (BMC) of the spine, hip, and whole body during the primary (first 24 weeks) and extension treatment periods (up to 288 weeks).
Change From Baseline in Bone Mineral Density (BMD) as Measured by Dual-energy X-ray Absorptiometry (DXA) Baseline, every 24 weeks through Week 96, then every 48 weeks until Week 288. A DXA scan was performed to evaluate bone bone mineral density (BMD) of the spine, hip, and whole body during the primary (first 24 weeks) and extension treatment periods (up to 288 weeks).
Change From Baseline in HPP-related Osteomalacia as Measured by Trans-iliac Crest Bone Biopsy: Osteoid Volume/Bone Volume Baseline, Week 24 (Control group), and Week 48 (Asfotase alfa groups). A trans-iliac crest bone biopsy was performed to quantify changes from Baseline in histomorphometric parameters relevant for evaluation of osteomalacia severity, including Osteoid Volume/Bone Volume (%). The difference in time under observation between asfotase alfa groups (Week 48) and control group (Week 24) resulted from study design, ie, control subjects transitioned to active treatment after the Week 24 visit.
Change From Baseline in HPP-related Osteomalacia as Measured by Trans-iliac Crest Bone Biopsy: Mineralization Lag Time Baseline, Week 24 (Control group), and Week 48 (Asfotase alfa groups). A trans-iliac crest bone biopsy was performed to quantify changes from Baseline in histomorphometric parameters relevant for evaluation of osteomalacia severity, including Mineralization Lag Time (days). The difference in time under observation between asfotase alfa groups (Week 48) and control group (Week 24) resulted from study design, ie, control subjects transitioned to active treatment after the Week 24 visit.
Trial Locations
- Locations (3)
Health Sciences Centre Winnipeg, University of Manitoba
🇨🇦Winnipeg, Manitoba, Canada
Shriner's Hospital for Children
🇺🇸Saint Louis, Missouri, United States
Duke University Medical Center
🇺🇸Durham, North Carolina, United States