An observational study in Ectonucleotide Pyrophosphatase/phosphodiesterase1 Deficiency, ATP-Binding Cassette Subfamily C Member 6 Deficiency and Generalized Arterial Calcification of Infancy, sponsored by Inozyme Pharma. Completed at 8 sites in 4 countries. Open to participants aged 1 Day and older. Per ClinicalTrials.gov, last updated 2026-08-04.
Sponsored by Inozyme Pharma (part of BioMarin Pharmaceutical) · Observational
The purpose of this study is to characterize the natural history of ectonucleotide pyrophosphatase/phosphodiesterase 1 (ENPP1) Deficiency and the early-onset form of adenosine triphosphate binding cassette transporter subfamily C member 6 (ABCC6) Deficiency through retrospective review of medical records and other available data sources. Information collected on medical history, clinical manifestations, radiographic imaging, and other disease-related assessments may be used to support the development of future therapies for these diseases.
Study INZ701-006 is a multicenter, retrospective, observational natural history study designed to evaluate disease presentation and progression in infant, pediatric, and adult subjects with ectonucleotide pyrophosphatase/phosphodiesterase 1 (ENPP1) Deficiency and in subjects with the early-onset form of adenosine triphosphate-binding cassette transporter subfamily C member 6 (ABCC6) Deficiency.
The study will utilize data obtained from medical records, radiographic imaging, and other available sources to characterize the physiological, anatomical, and functional manifestations of ENPP1 Deficiency and early-onset ABCC6 Deficiency.
For eligible subjects, historical data will be retrospectively abstracted from medical records and other available sources from birth, or earlier when available, through the date of informed consent, loss to follow-up, death, or another defined data cutoff, as applicable.
No study intervention will be administered as part of this observational study.
32 studies on the registry are indexed under Pseudoxanthoma Elasticum; 6 are open to participants now.
This study's enrollment of 23 is below the median of 80 across 15 observational studies indexed under Pseudoxanthoma Elasticum.
Browse Pseudoxanthoma Elasticum studies →Inozyme Pharma is the lead sponsor of 12 studies on the registry; none are open to participants now.
Of its 6 completed or terminated interventional studies of FDA-regulated products, 2 (33%) have results posted.
First submitted before Inozyme Pharma became part of BioMarin Pharmaceutical.
Counted across the registry records on this site, refreshed daily.
Infant, pediatric, and adult participants with ENPP1 Deficiency or early-onset ABCC6 Deficiency, including participants with generalized arterial calcification of infancy (GACI), whose diagnoses were confirmed by genetic testing and/or clinical phenotype and who had medical records available for retrospective review.
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.
Participants were eligible for inclusion if they met at least one of the following criteria:
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.
A biopsy takes a small piece of tissue to examine. “Archival tissue” is a sample already taken, for example at diagnosis, and kept by the hospital.
Whether a stored sample will do depends on when it was taken, how much there is and what the study needs. Ask whether the study accepts your stored sample or needs a new biopsy.
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.
Biopsy and archival tissue
A biopsy takes a small piece of tissue to examine. “Archival tissue” is a sample already taken, for example at diagnosis, and kept by the hospital.
Whether a stored sample will do depends on when it was taken, how much there is and what the study needs. Ask whether the study accepts your stored sample or needs a new biopsy.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
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.
Participants with Ectopic Calcification
Assessment of the occurrence of ectopic calcification documented in available imaging records. Ectopic calcification was identified based on radiologist or investigator interpretation of imaging assessments. The measure was the number of participants with documented ectopic calcification.
Time frame: Retrospective assessment of available historical records collected from birth through informed consent, loss to follow-up, or death, whichever occurred first (up to approximately 33 years).
Participants With Disease-Related Skeletal Abnormalities
Assessment of the occurrence of disease-related skeletal abnormalities documented in available medical records and imaging reports. Skeletal abnormalities were identified based on clinical diagnoses and radiographic findings recorded by treating physicians. The measure was the number of participants with documented skeletal abnormalities.
Time frame: Retrospective assessment of available historical records collected from birth through informed consent, loss to follow-up, or death, whichever occurred first (up to approximately 33 years).
Global Rickets Severity Score
Assessment of rickets severity using the Global Rickets Severity Score (RSS), which was derived from radiographic evaluations. Score (0 to 10), with higher scores indicating greater severity of rickets.
Time frame: Retrospective assessment of available radiographic evaluations collected from birth through informed consent, loss to follow-up, or death, whichever occurred first (up to approximately 33 years).
Height Z-Score
Assessment of longitudinal growth using height measurements obtained from medical records. Height measurements were converted to age- and sex-adjusted height Z-scores using WHO and CDC growth standards. The measured variable was height Z-score, reported as standard deviations (SD) from the reference population mean.
Time frame: Retrospective assessment of available height measurements collected from birth through informed consent, loss to follow-up, or death, whichever occurred first (up to approximately 33 years).
Weight Z-Score
Assessment of longitudinal growth using weight measurements obtained from medical records. Weight measurements were converted to age- and sex-adjusted weight Z-scores using WHO and CDC growth standards. The measured variable was weight Z-score, reported as standard deviations (SD) from the reference population mean.
Time frame: Retrospective assessment of available weight measurements collected from birth through informed consent, loss to follow-up, or death, whichever occurred first (up to approximately 33 years).
Serum Phosphate Concentration
Assessment of serum phosphate concentration obtained from clinical laboratory evaluations documented in medical records. The measured variable was serum phosphate concentration, reported in milligrams per deciliter (mg/dL) or converted to a common unit for analysis where appropriate.
Time frame: Retrospective assessment of available serum phosphate measurements collected from birth through informed consent, loss to follow-up, or death, whichever occurred first (up to approximately 33 years).
Fibroblast Growth Factor 23 (FGF23) Concentration
Assessment of fibroblast growth factor 23 (FGF23) concentration obtained from clinical laboratory evaluations documented in medical records. The measured variable was FGF23 concentration, reported in picograms per milliliter (pg/mL) according to local laboratory methodology.
Time frame: Retrospective assessment of available FGF23 measurements collected from birth through informed consent, loss to follow-up, or death, whichever occurred first (up to approximately 33 years).
Parathyroid Hormone (PTH) Concentration
Assessment of parathyroid hormone (PTH) concentration obtained from clinical laboratory evaluations documented in medical records. The measured variable was serum PTH concentration, reported in picograms per milliliter (pg/mL) according to local laboratory methodology.
Time frame: Retrospective assessment of available PTH measurements collected from birth through informed consent, loss to follow-up, or death, whichever occurred first (up to approximately 33 years).
Inorganic Pyrophosphate (PPi) Concentration
Assessment of inorganic pyrophosphate (PPi) concentration obtained from clinical laboratory evaluations documented in medical records. The measured variable was PPi concentration, reported in micromoles per liter (µmol/L) according to local laboratory methodology.
Time frame: Retrospective assessment of available PPi measurements collected from birth through informed consent, loss to follow-up, or death, whichever occurred first (up to approximately 33 years).
Plan to share: No — This data was collected for clinical trial planning and publication purposes by the Sponsor
No publications or documents are linked to this record.
Ran from Dec 2018 to primary completion in Jun 2023, 54 months.
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This study is completed, as verified in Jul 2026. You cannot join it, but the record below documents what was studied.
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