Safety Study of Human Recombinant Tissue Non-Specific Alkaline Phosphatase Fusion Protein Asfotase Alfa in Adults With Hypophosphatasia (HPP)

Hypophosphatasia (HPP) Clinical Trial

Official title:

A Multicenter, Open-Label, Dose Escalating Study of the Safety, Tolerability and Pharmacology of Human Recombinant Tissue Non-Specific Alkaline Phosphatase Fusion Protein Asfotase Alfa in Adults With Hypophosphatasia (HPP)

Clinical Trial Details — Status: Completed

Administrative data

• NCT number: NCT00739505
• Other study ID #: ENB-001-08
• Status: Completed
• Phase: Phase 1
• Start date: August 2008
• Est. completion date: February 2009

Study information

• Verified date: March 2019
• Source: Alexion Pharmaceuticals
• Contact: n/a
• Is FDA regulated: No
• Study type: Interventional

Clinical Trial Summary

This clinical trial studies the safety, tolerability, and pharmacology of asfotase alfa when given to adults with HPP.

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 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.

Recruitment information / eligibility

• Status: Completed
• Enrollment: 6
• Est. completion date: February 2009
• Est. primary completion date: January 2009
• Accepts healthy volunteers: No
• Gender: All
• Age group: 18 Years to 80 Years

Eligibility

Inclusion Criteria:

In order to qualify for participation, patients must meet all of the following criteria:

• Patients must provide written informed consent, including privacy authorization, prior to participation.

• Women of childbearing potential must sign the Women of Childbearing Potential Addendum and must be using an acceptable method of birth control. Women considered not of childbearing potential must be surgically sterile (total hysterectomy, bilateral salpingo-oophorectomy, or tubal ligation) or post-menopausal, which is defined as a complete cessation of menstruation for at least one year after the age of 45 years. All women must have a serum pregnancy test conducted at Screening prior to enrollment and the results must be negative.

• Be between 18 and 80 years of age at the time of consent

• Patients must be medically stable in the opinion of the Investigator.

• Patients must be willing to comply with study procedures and the visit schedule.

• Pre-established clinical diagnosis of HPP as indicated by:

• a. Serum alkaline phosphatase at least 3 SD below the mean for age

• b. Radiologic evidence of osteopenia or osteomalacia

• c. Two or more HPP-related findings:

• i. Plasma pyridoxal 5'-phosphate at least 2.5 SD above the mean (no vitamin B6 administered for at least 1 week prior to determination

• ii. History of rickets

• iii. History of premature loss of deciduous teeth

• iv. Bone deformity consistent with osteomalacia or past history of rickets

• v. History of any one of the following:

• 1. Non-traumatic fracture

• 2. Pseudofracture

• 3. Non-healing fracture

Exclusion Criteria:

In order to qualify for participation, patients must not meet any of the following criteria:

• Women who are pregnant or lactating.

• History of sensitivity to any of the constituents of the study drug.

• Low levels of serum calcium, magnesium or phosphate.

• Serum 25(OH) vitamin D level below 9.2 ng/mL.

• Elevated serum creatinine or parathyroid hormone level.

• Known cause of hypophosphatasemia other than HPP.

• Current or prior clinically significant cardiac, endocrinologic, hematologic, hepatic, immunologic, metabolic, urologic, pulmonary, neurologic, dermatologic, psychiatric, renal condition and/or other major disease which, in the opinion of the investigator, precludes study participation.

• Treatment with a bisphosphonate or parathyroid hormone (PTH) within 6 months prior to the start of Asfotase Alfa administration.

• Participation in an interventional or investigational drug study within 30 days prior to study participation.

Related Conditions & MeSH terms

• Hypophosphatasia
• Hypophosphatasia (HPP)

Intervention

Biological:
• Asfotase Alfa
The initial IV dose to be administered to patients was set at one-tenth the no adverse effect level (NOAEL) as determined by one month toxicology studies in animals in which Asfotase Alfa was administered as a single weekly IV dose. The SC doses to be administered are lower than the IV doses and are thought to be near or at the anticipated daily efficacious dose. Dosing will be as follows: Cohort 1: In Week 1, patients will receive an IV infusion of Asfotase Alfa at a dose of 3 mg/kg. In Weeks 2, 3 and 4, patients will receive weekly SC injections of Asfotase Alfa at a dose of 1 mg/kg SC.
• Asfotase Alfa
Cohort 2: In Week 1, patients will receive an IV infusion of Asfotase Alfa at a dose of 7 mg/kg. In Weeks 2, 3 and 4, patients will receive weekly SC injections of Asfotase Alfa at a dose of 1.5 mg/kg SC.

Locations

Country	Name	City	State
Canada	Department of Pediatrics & Child Health, Health Sciences Centre Winnipeg, University of Manitoba	Winnipeg	Manitoba
United States	Duke University Medical Center	Durham	North Carolina
United States	Barnes Jewish Hospital- Washington University School of Medicine	Saint Louis	Missouri

Sponsors (1)

Lead Sponsor	Collaborator
Alexion Pharmaceuticals

Countries where clinical trial is conducted

United States,  Canada, 

References & Publications (2)

Drake MT, Khosla S. Bone-targeted replacement therapy for hypophosphatasia. J Bone Miner Res. 2008 Jun;23(6):775-6. doi: 10.1359/jbmr.080305. — View Citation

Millán JL, Narisawa S, Lemire I, Loisel TP, Boileau G, Leonard P, Gramatikova S, Terkeltaub R, Camacho NP, McKee MD, Crine P, Whyte MP. Enzyme replacement therapy for murine hypophosphatasia. J Bone Miner Res. 2008 Jun;23(6):777-87. — View Citation

Outcome

Type	Measure	Description	Time frame	Safety issue
Primary	To determine the safety and tolerability of Asfotase Alfa given intravenously and given subcutaneously.		Within the first 2 months (8 weeks).
Secondary	To assess the pharmacokinetics (PK) of Asfotase Alfa given intravenously and subcutaneously		Within the first 2 months (8 weeks)
Secondary	To assess the bioavailability of the subcutaneous Asfotase Alfa		Within the first 2 months (8 weeks)

External Links

•   HPP support group
•   Hypophosphatasia Website
•   Hypophosphatasia Website for Healthcare Providers
•   Hypophosphatasie Europe
•   US Hypophosphatasia Group (Soft Bones)
•   Yahoo health group for HPP with an international list serve where patients can correspond and post questions to the group