ClinicalTrials.gov record NCT07390240
The Effect of Monoallelic Variants in the ALPL Gene on the Natural Course of Hypophosphatasia in Russia
The Effect of Monoallelic Variants in the ALPL Gene on the Natural Course of Hypophosphatasia (HPP) in Children and Adults in Russia
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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 non-interventional, multi-center cohort study in Russia follows people with hypophosphatasia who carry a single (monoallelic) ALPL gene variant. Investigators will collect clinical records, laboratory and imaging results, functional tests, and questionnaires at baseline to describe disease features. About 70 children and people monitored in routine care will be included.
What it is studying. The study aims to describe the natural course and clinical features of symptomatic hypophosphatasia in people who have a single (monoallelic) variant in the ALPL gene. Key questions include age at symptom onset and diagnosis, types and locations of skeletal, dental, muscular, renal, respiratory and neurologic problems, laboratory and radiologic findings, functional status, and quality‑of‑life measures.
What the researchers hope to learn. To scientifically describe how monoallelic ALPL variants relate to the presentation and course of symptomatic hypophosphatasia: age at onset and diagnosis, organ‑specific manifestations, laboratory and imaging patterns, functional performance, and quality‑of‑life.
What this study is about
The study's own summary, as published on ClinicalTrials.gov. Underlined terms have a short explanation.
The effect of monoallelic variants in the ALPL gene on the natural course of hypophosphatasia (HPP) in children and adults in Russia (ATLANTIS)
Eligibility
The criteria exactly as listed on ClinicalTrials.gov. Only the study team can say whether they apply to you.
Inclusion criteria
- Age ≥4 to <18 years, or ≥18 years at the time of enrollment;
- Signed ICF for patients ≥18 years, or legal representatives (parents) of patients aged ≥4 to <18 years;
- Written informed assent (for patients aged ≥14 to <18 years only);
- No history of HPP treatment with enzyme-replacement therapy;
- Diagnosis of symptomatic HPP confirmed by the presence of ALL of the following criteria:
- reduced alkaline phosphatase (ALP) activity relative to age- and sex-specific reference ranges, confirmed by at least two separate measurements;
- the identification of a monoallelic pathogenic, likely pathogenic, or variant of uncertain significance in the ALPL gene on genetic testing;
- presence of clinically relevant manifestations*, consistent with HPP, confirmed by at least one of the following: i. Musculoskeletal pain requiring medical intervention or limiting activities of daily living, present at screening or documented within the previous 12 months (e.g., based on medical records, functional test results, treatment prescriptions and/or rehabilitation interventions); chronic or recurrent pain lasting ≥3 months may be considered based on medical history beyond the 12-month period prior to screening, provided appropriate documentation is available; ii. Muscle weakness and/or reduced physical function (e.g., impaired mobility, increased fatigue), present at screening or documented within the previous 12 months (e.g., based on medical records, functional test results, treatment prescriptions and/or rehabilitation interventions); iii. History of fractures, pseudofractures, or delayed fracture healing, confirmed by medical documentation and/or imaging studies performed within 24 months prior to screening (provided no subsequent interventions have occurred that may have altered the findings; if such interventions have occurred, repeat imaging may be performed at the investigator's discretion, if applicable within routine clinical practice); iv. Skeletal abnormalities (e.g., radiographic signs of rickets/osteomalacia), confirmed by medical documentation and/or imaging studies performed within 24 months prior to screening (provided no subsequent interventions have occurred that may have altered the findings; if such interventions have occurred, repeat imaging may be performed at the investigator's discretion, if applicable within routine clinical practice); v. Dental manifestations (e.g., premature loss of deciduous teeth with intact roots before the age of 5 years without significant trauma), confirmed by medical and/or dental records; vi. Limitation in mobility, endurance, or activities of daily living, present at screening or documented within the previous 12 months based on routine clinical assessment using questionnaires, scales, functional tests and/or other relevant clinical tools used in routine practice; such tools may include, for example, the 6-minute walk test (6MWT), Timed Up-and-Go test, Chair-Rise test, Borg scale, IPAQ, PedsQL, EQ 5D-3L, bioimpedance measurements, and other methods used in routine clinical practice; if symptoms are present at screening, confirmation may be based on clinical assessments performed within 3 months prior to screening (provided there are no clinically significant changes in the patient's condition) or at the screening visit; vii. Need for analgesics, physiotherapy, and/or other supportive care for clinical manifestations of HPP, present at screening or during the period prior to screening, confirmed by at least one of the following criteria (based on medical records):
- regular use of analgesics (≥3 times per week for at least 4 consecutive weeks) within the previous 6 months, or escalation of analgesic therapy within the previous 6 months;
- ≥1 structured course of physiotherapy and/or rehabilitation interventions prescribed for musculoskeletal manifestations of HPP within the previous 12 months, or ongoing sessions according to specialist recommendations;
- use of non-pharmacological and/or medical measures to reduce symptoms and support function, including orthoses, insoles, assistive devices, local injections, or other symptomatic interventions; viii. Other clinical manifestations associated with HPP, in the investigator's opinion, present at screening or documented within the previous 12 months (based on clinical assessment and/or medical records).
Exclusion criteria
- Confirmed conditions presenting with clinical features overlapping with HPP, including but not limited to: cerebral palsy, Duchenne muscular dystrophy, limb-girdle muscular dystrophy (Erb Roth dystrophy), acquired secondary myopathies of various etiologies;
- Current participation in any clinical study (patients participating in other non interventional studies may be included);
- Homozygous or compound heterozygous mutation in the ALPL gene;
- Monoallelic pathogenic, likely pathogenic, or variant of uncertain significance in the ALPL gene in the absence of clinically relevant manifestations of HPP at the time of screening and/or in medical history consistent with the inclusion criterion #5;
- In the opinion of the investigator, the patient is not able to return for follow-up visits or obtain required follow-up studies;
- Pregnant and breastfeeding women.
Study description and what participation involves
The study's detailed description, as published on ClinicalTrials.gov.
Detailed description from the registry
Non-interventional, multi-center, cohort study for evaluation of clinical and patient reported outcomes in routine care settings
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.
Participants attend a baseline visit (Day 0 / Visit 1) where the study team will collect medical and family history and review medical records. The study records or collects routine clinical measures and tests used in care—examples listed in the registry include blood and urine laboratory results, genetic test results, X‑rays, physical function tests (6‑Minute Walk Test, Timed Up and Go, Chair‑Rise), muscle tone assessments (Modified Ashworth and Tardieu scales), bioimpedance measurements, and quality‑of‑life questionnaires (PedsQL, EQ‑5D‑3L, IPAQ). The registry requires prior documentation of a diagnosis of symptomatic HPP (including at least two reduced alkaline phosphatase measurements and identification of a monoallelic ALPL gene variant) and no history of enzyme‑replacement therapy; these requirements are checked for eligibility and are not necessarily performed by the study. Imaging already done within the specified time windows may be used, or repeat imaging may be obtained at the investigator's discretion as part of routine clinical care.
How the study is structured. Non-interventional observational cohort done at multiple clinical centers. Participants are not assigned treatments; study staff will collect baseline (Day 0 / Visit 1) information from routine clinical assessments and records. Data gathered include laboratory results (for example alkaline phosphatase and other blood/urine tests), imaging reports and radiographs, recorded ALPL gene variant information, functional tests when available (for example 6‑minute walk, Chair‑Rise, Timed Up and Go), bioimpedance measures, and patient‑reported questionnaires (for example PedsQL, EQ‑5D‑3L, IPAQ). The registry record does not specify follow‑up schedule or overall study duration.
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 Russia. 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
Important dates
- Study start
- Dec 29, 2025
- Primary completion
- Jun 30, 2030 (estimated)
- Study completion
- Jun 30, 2030 (estimated)
- Target enrollment
- 55 participants (estimated)
- Last updated on registry
- Sep 28, 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
- AstraZeneca
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.
- AstraZeneca Clinical Study Information Center 📞 1-877-240-9479 ✉ information.center@astrazeneca.com
Participating sites (4)
- Research siteCompleted
Moscow · Russia
- Research SiteRecruiting
Moscow · Russia
- Research SiteRecruiting
Rostov-on-Don · Russia
- Research siteRecruiting
Saint Petersburg · Russia
Terms used on this page · explanations by MedicalUpdates.ai
- enrollment
- The number of participants a study plans to include, or has included. 'Estimated' means the planned number; 'actual' means the number who joined.
- ICF
- 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.
- assent
- A child's or dependent adult's agreement to take part, given alongside the formal consent of a parent or legal representative.
- at screening
- The checks done before enrolment to see whether a person qualifies, such as tests, scans or a review of medical history.
- 6-minute walk test
- A test of how far a person can walk on a flat surface in six minutes. It is used to measure stamina and to track change over time.
- interventional
- A study in which researchers assign participants to one or more interventions, such as a drug, procedure, device, behavioural programme or other approach, to measure their effects.
- follow-up
- The period after treatment or enrolment during which participants are observed or contacted, for example to record side effects or outcomes.
- 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.
- cohort study
- A group of people who share a characteristic, such as a diagnosis, and are studied together. 'Prospective' means they are followed forward from enrolment; 'retrospective' means existing records are reviewed.
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.
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