ClinicalTrials.gov record NCT02237625

Natural History Study of Patients With Hypophosphatasia (HPP)

Record copied from ClinicalTrials.gov: Oct 10, 2026AI summaries generated: Jul 27, 2026

Natural History Study of Adult and Pediatric Patients With Hypophosphatasia

StatusRecruitingThe study is currently enrolling participants. Only the study team can say whether a particular person can join.
Study typeObservationalA study in which researchers do not assign participants to a treatment or other intervention. They observe or measure what happens, which may include study visits, tests, questionnaires or a review of medical records.
SexAll
LocationUnited States
AI summaryWhat this study is about, in plain languageShow ▾Hide ▴

AI-written from the registry record, not the study's own wording. May contain errors or omissions. Check the registry text on this page and the original record ↗ before acting on it.

This is a long-term observational natural history study collecting medical and clinical data from people with hypophosphatasia (HPP) of any age. It aims to document how HPP begins and changes over time, including symptoms, complications, and how treatments are used. The study is prospective and planned to follow participants for up to 100 years.

What it is studying. The study is documenting the natural history of HPP: diagnosis, onset, progression, extent of bone and tooth disease, involvement of other organs (for example eye, kidney, musculoskeletal), potential long-term complications, long-term outcomes of treatments, and quality of life.

What the researchers hope to learn. Create a comprehensive clinical database for HPP; characterize disease course and organ involvement across ages; describe potential long-term complications and long-term outcomes of treatments; and document quality of life issues for people living with HPP.

What this study is about

The study's own summary, as published on ClinicalTrials.gov. Underlined terms have a short explanation.

Hypophosphatasia (HPP) is a rare inherited metabolic disorder characterized by defective bone and teeth mineralization caused by mutations of the ALPL gene, which encodes for the tissue-nonspecific alkaline phosphatase (TNSALP) isozyme, resulting in decreased serum and bone alkaline phosphatase levels. To date, over 250 different mutations in the gene encoding TNSALP have been associated with HPP. Clinically, the loss of TNSALP function results in progressive skeletal impact as well as progressive impact on all other major organ systems. It clinically manifests as rickets in infants and children and osteomalacia at all ages. The severe form of the disease has been estimated to have a prevalence of about 1 in every 100,000 live births.

Eligibility

The criteria exactly as listed on ClinicalTrials.gov. Only the study team can say whether they apply to you.

Inclusion criteria

  • Patients or their legal representative must provide written informed consent or, if applicable, qualify for waiver of consent.
  • Patients must have a pre-established clinical diagnosis of HPP, as indicated by one or more of the following:
  • Serum alkaline phosphatase (ALP) below the age-adjusted normal range
  • Plasma PLP at least twice the upper limit of normal (no vitamin B6 administered for at least 1 week prior to determination)
  • Evidence of osteopenia or osteomalacia on skeletal radiographs
  • Genetic analysis fof the ALPL gene
  • Must be current patient in the Duke University System.

Exclusion criteria

  • Any patient without confirmation of clinical diagnosis of HPP.

Study description and what participation involves

The study's detailed description, as published on ClinicalTrials.gov.

Detailed description from the registry

Inheritance can be autosomal recessive or dominant, and penetrance is variable resulting in a wide range of clinical expressivity, with a spectrum ranging from stillbirth without mineralized bone to early loss of teeth without bone symptoms. Depending on the age at diagnosis six clinical forms are currently recognized: perinatal (lethal), perinatal benign, infantile, childhood, adult and odontohypophosphatasia. Severe forms of HPP (perinatal and infantile) are inherited as an autosomal recessive trait and in milder forms (adult and odontohypophosphatasia) autosomal recessive and autosomal dominant inheritance coexist. Because of the rarity of HPP as well as the side spectrum of both clinical presentation and inheritance patterns of the HPP trait, a natural history study cataloging specific clinical data with HPP would prove invaluable for future research into this disease. Specifically, it is our goal to create a comprehensive multi-discipline modality for care for hypophosphatasia patients, researching clinical manifestations of the disease such as extent of bone disease, ophthalmologic manifestations, orthopedic issues, renal issues, musculoskeletal manifestations as well as other more anecdotal findings such as those seen with cochlear implant failures and/or early menopause.

AI summaryWhat participation may involve, in plain languageShow ▾Hide ▴

AI-written from the registry record, not the study's own wording. May contain errors or omissions. Check the registry text on this page and the original record ↗ before acting on it.

The study involves collection and storage of clinical and medical-history data about people with HPP, including diagnosis, onset, disease course, treatments, complications, and outcomes. Participation involves review and capture of your medical-record information and long-term follow-up (the registry lists follow-up up to 100 years). The registry record does not specify particular invasive procedures; the exact tests, visit schedule, or questionnaires to be used are not detailed in the public record.

How the study is structured. An observational, family-based registry. No treatments are assigned. Researchers collect and store medical history and clinical data and follow participants prospectively over time. Up to 100 minor and 100 adult participants are planned, with a target follow-up period of up to 100 years.

Questions you could ask

These questions are suggestions for a conversation with the study team or your own clinician, not advice.

  • This is an observational study, so the study itself gives no treatment. What would taking part involve for me, and would it change my usual care?
  • The listed sites are in United States. Is any of them reachable for me, and does the study help with travel?
  • Which of the eligibility criteria would need to be checked with tests before I could join?

More on hypophosphatasia

Clinical trials9 trials listed for hypophosphatasiaEvery trial the registry lists for hypophosphatasia, with recruitment status, phase and sites, updated from ClinicalTrials.gov.See all trials →Research updatesWhat changed in hypophosphatasia researchLatest monthly update: September 2026. Includes: Early lab flag. New research summarized each month in plain language, with links to every source paper.Read the latest update →

Important dates

Study start
September 2014
Primary completion
September 2027 (estimated)
Study completion
September 2028 (estimated)
Target enrollment
200 participants (estimated)
Last updated on registry
Mar 5, 2026
Data verified
Oct 10, 2026

Sponsor and research team

The lead sponsor funds and oversees the trial. A pharmaceutical or biotech company sponsor typically means the study is testing that company's drug or device; a hospital, university, or government agency usually indicates investigator-initiated or publicly funded research.

Lead sponsor
Duke University

Central study contact

If you're interested in participating, the central contact can answer general questions about the study — including eligibility requirements and how to find a recruiting site near you. Actual eligibility is determined by the site's medical team.

Participating sites (1)

Terms used on this page · explanations by MedicalUpdates.ai

legal representative
A person who is legally allowed to make decisions, including consent to research, on behalf of someone who cannot consent for themselves.
written informed consent
The process of explaining a study, including its risks and what participation involves, so that a person can decide freely whether to take part. Consent is usually documented in writing, and a participant can choose to leave the study later.
upper limit of normal
The highest value of a blood test that a laboratory considers normal. Criteria such as '≤ 3 × ULN' mean the result must be no more than three times that value.
Inclusion Criteria
The conditions a person must meet to be considered for the study, for example a confirmed diagnosis, an age range or a test result.
Exclusion Criteria
The conditions that rule a person out even if they meet the inclusion criteria, for example other illnesses, certain medicines or pregnancy.
natural history study
A study that follows how a condition changes over time without assigning an experimental treatment. It may involve study visits and tests, and is often used to plan future trials.

The study record on this page is reproduced from ClinicalTrials.gov, a database of the U.S. National Library of Medicine, where it was submitted by the study sponsor. MedicalUpdates.ai does not own this content, is not affiliated with or endorsed by ClinicalTrials.gov, NIH, or the U.S. Government, and does not verify the record. Plain-language notes, the glossary and the questions above are added by this site; text in the boxes marked "AI summary" was written by an AI model and may contain errors. Registry records change over time. Check the original record for the current version and discuss eligibility or participation with a qualified healthcare professional.

← Back to clinical trials