A Prospective Sub-Study of the Global Hypophosphatasia Registry

A Prospective Observational Sub-Study of the Global Hypophosphatasia Registry to Describe the Potential Risk of Immune-Mediated Loss of Pharmacological Effect of Asfotase Alfa in Participants With Hypophosphatasia

In this prospective observational sub-study, participants with pediatric-onset hypophosphatasia (HPP) (perinatal/infantile- or juvenile-onset) of any age will be followed for a minimum of 5 years at sites in the United States and potentially 1 or 2 other countries.

Study Overview

• Status: Recruiting
• Conditions: Hypophosphatasia
• Intervention / Treatment: Biological: Asfotase Alfa

• Study Type: Observational
• Enrollment (Estimated): 40

Contacts and Locations

• Study Contact: Name: Alexion Pharmaceuticals, Inc.; Phone Number: 1.855.752.2356; Email: clinicaltrials@alexion.com

Study Locations

• United States
  • Connecticut
    • Hartford, Connecticut, United States, 06106
      • Recruiting
      • Clinical Trial Site
  • Illinois
    • Chicago, Illinois, United States, 60611
      • Not yet recruiting
      • Clinical Trial Site
  • Massachusetts
    • Boston, Massachusetts, United States, 02122
      • Recruiting
      • Clinical Trial Site
  • Missouri
    • Kansas City, Missouri, United States, 64108
      • Recruiting
      • Clinical Trial Site
  • Nevada
    • Las Vegas, Nevada, United States, 89113
      • Not yet recruiting
      • Clinical Trial Site
  • New York
    • Mineola, New York, United States, 11501
      • Recruiting
      • Clinical Trial Site
  • Ohio
    • Cincinnati, Ohio, United States, 45229
      • Not yet recruiting
      • Clinical Trial Site
    • Columbus, Ohio, United States, 43203
      • Recruiting
      • Clinical Trial Site
  • Pennsylvania
    • Philadelphia, Pennsylvania, United States, 19104
      • Not yet recruiting
      • Clinical Trial Site
    • Pittsburgh, Pennsylvania, United States, 15224
      • Not yet recruiting
      • Clinical Trial Site
  • Tennessee
    • Nashville, Tennessee, United States, 37112
      • Recruiting
      • Clinical Trial Site
  • Utah
    • Salt Lake City, Utah, United States, 84108
      • Not yet recruiting
      • Clinical Trial Site
  • Virginia
    • Charlottesville, Virginia, United States, 22903
      • Not yet recruiting
      • Clinical Trial Site

Participation Criteria

Eligibility Criteria

• Ages Eligible for Study: Child; Adult; Older Adult
• Accepts Healthy Volunteers: No

• Sampling Method: Probability Sample

Study Population

Patients with HPP

Description

Inclusion Criteria:

• Any age or sex with a confirmed diagnosis of pediatric-onset HPP (that is, first HPP sign or symptom presented at < 18 years of age).
• Currently receiving asfotase alfa treatment at Enrollment (not treatment-naïve) or the Physician has decided to resume (not treatment-naïve) or start (treatment-naïve) the participant's asfotase alfa treatment within 6 months after Enrollment.
• Participant must have documented alkaline phosphatase (ALP) activity below the lower limit of normal for age and sex, and a documented ALPL gene mutation (Note: An exception is made for infants with clinical features of HPP plus low ALP who need to start asfotase alfa treatment right away, at the Physician's discretion, but do not yet have a genetic result. In this case, ALPL gene documentation is not required at the time of sub-study enrollment but should be documented within 6 months after Enrollment).
• Participant or participant's parent/legally authorized representative is able to read and/or understand the informed consent and study questionnaires in the local language.
• Participant or participant's parent/legally authorized representative must be willing and able to give signed informed consent for this sub-study, and the participant must be willing to give written informed assent, if appropriate and required by local regulations.

Exclusion Criteria:

• Currently participating in an Alexion-sponsored interventional clinical study. Participants who have concluded participation in an Alexion-sponsored asfotase alfa clinical study are eligible to enroll in this sub-study.

Study Plan

How is the study designed?

Number of groups / cohorts

1

Cohorts and Interventions

Group / Cohort

Intervention / Treatment

Participants with Pediatric-onset HPP; Each participant will be followed for a minimum of 5 years or, if applicable, until early withdrawal. Biochemical, clinical, imaging (if clinically indicated), and functional/quality of life outcomes relevant to HPP will be assessed.

Biological: Asfotase Alfa; All participants will receive asfotase alfa subcutaneously per standard of care. Unless otherwise specified per the Physician's standard of care, participants aged < 2 years are recommended for a clinic visit approximately every 3 months after Enrollment until 2 years of age, after which they should have a clinic visit approximately every 6 months. Participants should be followed for 5 years, as possible.; Other Names: Strensiq

What is the study measuring?

Primary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Occurrence Of Immune-mediated Loss Of Effectiveness According To The Treating Physician	This will be based on clinical and biochemical assessments as well as positive anti-drug antibodies and positive neutralizing antibodies.	Up to 5 years
Occurrence Of Immune-mediated Serious Adverse Events	These serious adverse events will include serious hypersensitivity reactions and anaphylaxis.	Up to 5 years

Collaborators and Investigators

• Sponsor: Alexion

Study record dates

Study Major Dates

• Study Start (Actual): March 17, 2022
• Primary Completion (Estimated): June 30, 2028
• Study Completion (Estimated): June 30, 2028

Study Registration Dates

• First Submitted: February 1, 2022
• First Submitted That Met QC Criteria: February 1, 2022
• First Posted (Actual): February 10, 2022

Study Record Updates

• Last Update Posted (Actual): July 12, 2023
• Last Update Submitted That Met QC Criteria: July 11, 2023
• Last Verified: July 1, 2023

More Information

Terms related to this study

• Keywords: HPP; Pediatric Onset; Asfotase alfa
• Additional Relevant MeSH Terms: Metabolic Diseases; Genetic Diseases, Inborn; Metabolism, Inborn Errors; Metal Metabolism, Inborn Errors; Hypophosphatasia
• Other Study ID Numbers: ALX-HPP-501s

Plan for Individual participant data (IPD)

• Plan to Share Individual Participant Data (IPD)?: YES
• IPD Sharing Access Criteria: Alexion will consider requests for disclosure of clinical study participant-level data provided that participant privacy is assured through methods like data de-identification, pseudonymization, or anonymization (as required by applicable law), and if such disclosure was included in the relevant study informed consent form or similar documentation. Qualified academic investigators may request participant-level clinical data and supporting documents (statistical analysis plan and protocol) pertaining to Alexion-sponsored studies. Further details regarding data availability and instructions for requesting information are available in the Alexion Clinical Trials Disclosure and Transparency Policy at https://alexion.com/our-research/research-and-development.

Drug and device information, study documents

• Studies a U.S. FDA-regulated drug product: Yes
• Studies a U.S. FDA-regulated device product: No