An observational study in Hypophosphatasia (HPP), sponsored by Alexion Pharmaceuticals, Inc.. Enrolling by invitation at 67 sites in 13 countries. Per ClinicalTrials.gov, last updated 2026-11-04.
Sponsored by Alexion Pharmaceuticals, Inc. (part of AstraZeneca) · Observational
In this prospective, observational, long term registry patients of all ages with a diagnosis of hypophosphatasia (HPP) are followed at participating sites in multiple countries.
The HPP Registry is an observational, prospective, long-term registry designed to collect data on HPP epidemiology, disease history, clinical course, symptoms and burden of disease from patients of all ages who have a diagnosis of HPP.
Evaluation of safety and effectiveness data in patients with HPP who have/are receiving treatment with Asfotase alfa
46 studies on the registry are indexed under Hypophosphatasia; 11 are open to participants now.
This study's planned enrollment of 1,571 is above the median of 58 across 24 observational studies indexed under Hypophosphatasia.
Browse Hypophosphatasia studies →Alexion Pharmaceuticals, Inc. is the lead sponsor of 255 studies on the registry; 23 are open to participants now.
Of its 101 completed or terminated interventional studies of FDA-regulated products, 75 (74%) have results posted.
First submitted before Alexion Pharmaceuticals, Inc. became part of AstraZeneca.
Counted across the registry records on this site, refreshed daily.
Patients with Hypophosphatasia (HPP)
Go through the criteria one by one — yes, no or not sure — and take the list to your doctor or the study team. Kept in this browser only.
Exclusion Criteria:
Underlined terms in the criteria open these too. Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
Before you join, the study team explains what taking part involves — its purpose, what happens, the risks and possible benefits — and answers your questions, so you can decide freely. Consent is usually recorded on a form (the informed consent form, ICF) signed by you or, where the law allows, by someone legally authorised to decide for you.
You can keep asking questions during the study, you are told of new information that matters, and you can choose to leave at any time.
Informed consent
Before you join, the study team explains what taking part involves — its purpose, what happens, the risks and possible benefits — and answers your questions, so you can decide freely. Consent is usually recorded on a form (the informed consent form, ICF) signed by you or, where the law allows, by someone legally authorised to decide for you.
You can keep asking questions during the study, you are told of new information that matters, and you can choose to leave at any time.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
Natural History Information
To collect information on the natural history of HPP from patients of all ages, including pediatric patients and adults with HPP, regardless of age at onset.
Time frame: 1 Year
Burden of Disease/Patient-reported Outcomes
Age-appropriate PRO data will be collected using instruments to asses below: Pain, Motor Capacity, Functional Status/Disability, including Activities of Daily Living (ADL), Quality of Life (QoL)
Time frame: 1 year
Characterize the epidemiology of the HPP population.
To characterize the epidemiology of the HPP population. Inclusion of all classifications of HPP is planned: pediatric-onset (perinatal-, infantile-, and juvenile-onset), adult-onset, benign perinatal, and odontohypophosphatasia.
Time frame: 1 year
Long-Term Safety and Effectiveness of Asfotase Alfa
To collect and evaluate long-term safety and effectiveness data in HPP patients who have/are receiving treatment with asfotase alfa.
Time frame: 1 year
Started Jan 2015 (actual). Primary completion is estimated for Dec 2031, 203 months after the start.
How these figures are worked out, and which studies are left out of them.
From the registry record's own update history. This site started tracking changes on Sep 25, 2026; for anything earlier, see the record history on ClinicalTrials.gov ↗
Eligibility is decided by the study team. Share this record with your doctor or contact the team directly.
No contact was published for this record. The registry link below has the sponsor’s details.
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Alexion Pharmaceuticals, Inc. →