Ectonucleotide Pyrophosphatase/phosphodiesterase1 DeficiencyNCT05050669
Natural History Study of ENPP1 Deficiency and the Early-onset Form of ABCC6 Deficiency
An observational study of Ectonucleotide Pyrophosphatase/phosphodiesterase1 Deficiency and Generalized Arterial Calcification of Infancy, run by Inozyme Pharma at 5 sites in 3 countries.
Trial summary
The purpose of this prospective study is to characterize the natural history of ENPP1 Deficiency and the early-onset form of ABCC6 Deficiency longitudinally. The study will prospectively gather information about the biochemical, physiological, anatomic, radiographic, and functional manifestations (including patient… Read more about this study
- Who is it for?
- Ages 2 to 18 years
- Conditions the study is for
- Ectonucleotide Pyrophosphatase/phosphodiesterase1 Deficiency, Generalized Arterial Calcification of Infancy, Autosomal Recessive Hypophosphatemic Rickets
- How many people
- 12 participants
- Where
- 5 sitesin 3 countries
- Study dates
- 28 Jun 2022to 26 Jun 2024
- Phase
- Observational
- Are there results?
- None posted in the registry
Key requirements
Who can take part, as listed by the sponsor. Only the study team can confirm whether you are eligible, so take this list to your doctor.
- Ages 2 to 18 years
- All sexes
- No healthy volunteers
- Child, Adult
Study population: This study will enroll all eligible subjects aged 2 to <18 years with ENPP1 Deficiency and the early-onset form of ABCC6 Deficiency who consent to participate, with the goal of recruiting up to 20 subjects.
Who may be able to join
- Individuals eligible to participate must meet all of the following inclusion criteria:
- Must provide written consent of the legally authorized representative/caregiver and assent for subjects after the nature of the study has been explained and prior to any research-related procedures, following the policies of the clinical site
- Genetic confirmation of ENPP1 Deficiency or ABCC6 Deficiency
- Male or female, aged 2 to <18 years
- In the opinion of the Investigator, must be willing and able to complete all aspects of the study
- Agree to provide access to relevant medical records
Who cannot join
- Individuals who meet the following exclusion criterion will not be eligible to participate:
- 1. In the opinion of the Investigator and/or Sponsor, presence of any clinically significant disease (outside of those considered associated with the diagnosis of ENPP1 Deficiency or the early-onset form of ABCC6 Deficiency) that precludes study participation or may confound interpretation of study results, such as an unrelated bone, mineral, or muscle disease or genetic connective tissue disease
Trial locations and contacts
5 sites in 3 countries.
5 sites in 3 countries
United States3 sites
Boston Children's Hospital
Boston, Massachusetts, 02115
Cook Children's Hospital
Fort Worth, Texas, 76104
CHOP - Roberts Center for Pediatric Research
Philadelphia, Pennsylvania, 19146
United Kingdom1 site
Royal Manchester University Hospital
Manchester, Manchester, M13 9WL
About this study
Official title: A Prospective Observational Study to Evaluate Disease Presentation and Progression in Subjects With ENPP1 Deficiency and the Early-Onset Form of ABCC6 Deficiency
The purpose of this prospective study is to characterize the natural history of ENPP1 Deficiency and the early-onset form of ABCC6 Deficiency longitudinally. The study will prospectively gather information about the biochemical, physiological, anatomic, radiographic, and functional manifestations (including patient reported outcomes) of each disease.
Read the detailed description
Study INZ701-003 is a multicenter, prospective, longitudinal, observational study to evaluate disease presentation, progression, and burden of illness in pediatric subjects aged 2 to <18 years with ENPP1 Deficiency and the early-onset form of ABCC6 Deficiency. Subjects will receive care available at the clinical site along with additional assessments administered by the study team.
To participate in this study, subjects will give informed assent and parents/guardians will provide informed consent.
Subject participation will consist of a Screening Period and an Observation Period.
Assessments will be performed at each visit as indicated in the Schedule of Events.
During the Screening Period, assessments will be performed to determine eligibility.
Screening and Baseline assessments may be conducted on the same day if the Investigator determines that the patient can successfully complete all study procedures in one day due to their age. If not, sites may schedule additional visits, as needed. A subject will be enrolled into the study if they meet all eligibility criteria.
During the Observation Period, subjects will be assessed for changes in their disease in the following areas: measurements of physiological function (including laboratory testing and anatomical and radiographical assessment of calcification and bone mineralization); performance outcomes; patient, caregiver, and physician reported outcomes; and healthcare utilization.
- Conditions
- Ectonucleotide Pyrophosphatase/phosphodiesterase1 Deficiency, Generalized Arterial Calcification of Infancy, Autosomal Recessive Hypophosphatemic Rickets, Adenosine Triphosphate Binding Cassette Transporter Protein Subfamily C Member 6
- Being tested
- No Intervention for this observational study
- Keywords
- ectonucleotide pyrophosphatase/phosphodiesterase 1 deficiency, ENPP1, ATP-binding cassette subfamily C member 6 deficiency, ABCC6, Generalized Arterial Calcification of Infancy, GACI, Autosomal Recessive Hypophosphatemic Rickets Type 2, ARHR2, hypopyrophosphatemia, Early Onset Form
- Medical subject headings
- Arterial calcification of infancy, Hypophosphatemic Rickets, Autosomal Recessive, 1
What participants receive
What participants receive. In a randomised study each person is assigned to one group by chance.
No Intervention for this observational studyOther
No Intervention for this observational study
What is being measured
The primary outcome is the main question the study is designed to answer.
Measurement of Plasma Inorganic Pyrophosphate (PPi) in Plasma
For each subject, blood plasma will be assayed for Plasma Inorganic Pyrophosphate (PPi), comparing the subjects baseline value over time
Measured: Up to 12 months
Determination of Arterial Calcification
For each subject, occurrence of arterial calcification will be examined
Measured: Up to 12 months
Determination of Organ Calcification
For each subject, occurrence of organ calcification will be examined
Measured: Up to 12 months
Determination of skeletal radiographs
For each subject, skeletal radiographs will be obtained to determine skeletal abnormalities and will be compared to baseline
Measured: Up to 12 months
Determination of range of motion
For each subject, aged 4 to <18 years, range of motion will be assessed comparing to subjects baseline over time
Measured: Up to 12 months
Timeline
From the start of the study to its completion; the mark is today. Estimated dates are the sponsor’s plan.
- First posted20 Sep 2021
- Study start28 Jun 2022
- Primary completion31 May 2024
- Study completion26 Jun 2024
Resources
- Official record on ClinicalTrials.govThe registry entry this page is built from, with its full change history.
- Other trials for Ectonucleotide Pyrophosphatase/phosphodiesterase1 DeficiencyStudies of the same condition, open and under way.
- What the trial phases meanHow a treatment moves from first tests in people to approval.
More details
For doctors and researchers: how the study is designed, who runs it, and its registry IDs.
Study design
- Study type
- Observational
- Observational model
- Case only
- Time perspective
- Prospective
- Enrolment
- 12 participants (actual)
Sponsor and investigators
- Lead sponsor
- Inozyme Pharma
- Sponsor type
- Industry (pharma, biotech, devices)
- Responsible party
- Sponsor
IDs, dates and publications
- ClinicalTrials.gov ID
- NCT05050669
- Sponsor's protocol ID
- INZ701-003
- Status last verified
- Jul 2026
- First submitted
- 10 Sep 2021
- Last updated
- 6 Jul 2026
- Results posted
- No
- Data monitoring committee
- No
- FDA-regulated drug
- No
- FDA-regulated device
- No
- Individual data sharing
- No
Study at a glance
From the registry record, last updated by the sponsor on 6 Jul 2026. Recruitment status is as the sponsor reported it: confirm with the study team.
- Official title
- A Prospective Observational Study to Evaluate Disease Presentation and Progression in Subjects With ENPP1 Deficiency and the Early-Onset Form of ABCC6 Deficiency
- ClinicalTrials.gov ID
- NCT05050669
- Acronym / sponsor ID
- INZ701-003
- Conditions
- Ectonucleotide Pyrophosphatase/phosphodiesterase1 Deficiency, Generalized Arterial Calcification of Infancy, Autosomal Recessive Hypophosphatemic Rickets, Adenosine Triphosphate Binding Cassette Transporter Protein Subfamily C Member 6
- Keywords
- ectonucleotide pyrophosphatase/phosphodiesterase 1 deficiency, ENPP1, ATP-binding cassette subfamily C member 6 deficiency, ABCC6, Generalized Arterial Calcification of Infancy, GACI, Autosomal Recessive Hypophosphatemic Rickets Type 2, ARHR2
- Study type
- Observational
- Recruitment status
- Completed
- Enrolment
- 12 participants (actual)
- Lead sponsor
- Inozyme PharmaIndustry (pharma, biotech, devices)
- Study start
- 28 Jun 2022 (actual)
- Primary completion
- 31 May 2024 (actual)
- Study completion
- 26 Jun 2024 (actual)
- First posted
- 20 Sep 2021 (actual)
- Results
- Not posted in the source record
Clinical summary
The research question as the sponsor registered it. This describes what the study plans to test, not what it found.
The purpose of this prospective study is to characterize the natural history of ENPP1 Deficiency and the early-onset form of ABCC6 Deficiency longitudinally. The study will prospectively gather information about the biochemical, physiological, anatomic, radiographic, and functional manifestations (including patient reported outcomes) of each disease.
Detailed description
Study INZ701-003 is a multicenter, prospective, longitudinal, observational study to evaluate disease presentation, progression, and burden of illness in pediatric subjects aged 2 to <18 years with ENPP1 Deficiency and the early-onset form of ABCC6 Deficiency. Subjects will receive care available at the clinical site along with additional assessments administered by the study team.
To participate in this study, subjects will give informed assent and parents/guardians will provide informed consent.
Subject participation will consist of a Screening Period and an Observation Period.
Assessments will be performed at each visit as indicated in the Schedule of Events.
During the Screening Period, assessments will be performed to determine eligibility.
Screening and Baseline assessments may be conducted on the same day if the Investigator determines that the patient can successfully complete all study procedures in one day due to their age. If not, sites may schedule additional visits, as needed. A subject will be enrolled into the study if they meet all eligibility criteria.
During the Observation Period, subjects will be assessed for changes in their disease in the following areas: measurements of physiological function (including laboratory testing and anatomical and radiographical assessment of calcification and bone mineralization); performance outcomes; patient, caregiver, and physician reported outcomes; and healthcare utilization.
Study design
- Observational model
- Case only
- Time perspective
- Prospective
Who may qualify
- Ages
- 2 to 18 years
- Sex
- All
- Healthy volunteers
- Not accepted
- Age groups
- Child, Adult
- Study population
- This study will enroll all eligible subjects aged 2 to <18 years with ENPP1 Deficiency and the early-onset form of ABCC6 Deficiency who consent to participate, with the goal of recruiting up to 20 subjects.
Key inclusion criteria (6 listed)
- Must provide written consent of the legally authorized representative/caregiver and assent for subjects after the nature of the study has been explained and prior to any research-related procedures, following the policies of the clinical site
- Genetic confirmation of ENPP1 Deficiency or ABCC6 Deficiency
- Male or female, aged 2 to <18 years
- In the opinion of the Investigator, must be willing and able to complete all aspects of the study
- Agree to provide access to relevant medical records
Key exclusion criteria (2 listed)
- Individuals who meet the following exclusion criterion will not be eligible to participate:
- 1. In the opinion of the Investigator and/or Sponsor, presence of any clinically significant disease (outside of those considered associated with the diagnosis of ENPP1 Deficiency or the early-onset form of ABCC6 Deficiency) that precludes study participation or may confound interpretation of study results, such as an unrelated bone, mineral, or muscle disease or genetic connective tissue disease
Eligibility is decided by the study team after screening; this overview does not establish that a patient qualifies. Full inclusion and exclusion criteria.
Interventions
| Intervention | Type | Arms |
|---|---|---|
| No Intervention for this observational studyNo Intervention for this observational study | Other | – |
Primary outcome
Measurement of Plasma Inorganic Pyrophosphate (PPi) in Plasma
Time frame: Up to 12 months
For each subject, blood plasma will be assayed for Plasma Inorganic Pyrophosphate (PPi), comparing the subjects baseline value over time
Determination of Arterial Calcification
Time frame: Up to 12 months
For each subject, occurrence of arterial calcification will be examined
Determination of Organ Calcification
Time frame: Up to 12 months
For each subject, occurrence of organ calcification will be examined
Determination of skeletal radiographs
Time frame: Up to 12 months
For each subject, skeletal radiographs will be obtained to determine skeletal abnormalities and will be compared to baseline
Determination of range of motion
Time frame: Up to 12 months
For each subject, aged 4 to <18 years, range of motion will be assessed comparing to subjects baseline over time
Results and safety
The study is completed, but results are not available in the source record. That does not mean the treatment did or did not work.
Research links
- Official record on ClinicalTrials.govLast updated by the sponsor 6 Jul 2026.
- Individual participant dataSharing planned: No
Referral and contact
AzTrials does not enrol participants or take referrals. Contact the study team or a site listed below; they decide who can take part. This study is not recruiting at the moment.
The record lists no contact. Use the official record to reach the sponsor.
5 sites in 3 countries: see every site and its status.
Questions about this trial
What is this clinical trial studying?
An observational study of Ectonucleotide Pyrophosphatase/phosphodiesterase1 Deficiency and Generalized Arterial Calcification of Infancy, run by Inozyme Pharma at 5 sites in 3 countries.
The full registered description is in the About this study section and the official record.
Who may be eligible to take part?
The sponsor lists 6 inclusion and 2 exclusion criteria. Eligibility is decided by the study team after screening, so read the full criteria and contact a listed site.
Is this clinical trial currently recruiting?
The record says: finished, as of the sponsor's last update on 6 Jul 2026. Status can change between updates, so confirm with the study contact before making plans.
Where is the study taking place?
The record lists 5 sites in United States, Canada, United Kingdom. Whether a site is taking part right now should be confirmed with that site. See every site.
What are the possible benefits and risks?
They depend on the study and the treatment, and no study can promise a benefit. The study team explains the known risks during informed consent, before anyone joins; the record itself does not list them.
Are results available for this study?
The study is completed, but results are not available in the source record. That does not mean the treatment did or did not work.
How can a doctor refer a patient or contact the research team?
The record lists no contact. The official record names the sponsor, who can be asked directly. AzTrials does not enrol participants or take referrals.
What does the primary outcome measure?
Measurement of Plasma Inorganic Pyrophosphate (PPi) in Plasma (time frame: Up to 12 months). The study lists 5 primary outcomes in all. It is what the study was designed to measure, not a finding.
Where can I read the original study information?
Does a listing mean the treatment is approved or proven to work?
No. A listing means the study is registered. It does not show that the treatment is safe, works, or is approved by a regulator.
How often is this information updated?
AzTrials copies changed records from ClinicalTrials.gov every night and reloads the whole registry every week. The sponsor last updated this record on 6 Jul 2026.