A Phase 1 interventional study of INZ-701 in Ectonucleotide Pyrophosphatase/phosphodiesterase1 Deficiency, Autosomal Recessive Hypophosphatemic Rickets and Generalized Arterial Calcification of Infancy, sponsored by Inozyme Pharma. Terminated at 5 sites in 3 countries. Open to participants aged Up to 1 Year. Per ClinicalTrials.gov, last updated 2026-10-15.
Sponsored by Inozyme Pharma (part of BioMarin Pharmaceutical) · Phase 1, Interventional, and Treatment
The study was terminated by the sponsor prior to planned completion based on a review of the data across indications and overall program considerations. Study termination was not related to participant safety.
The primary purpose of Study INZ701-104 (the ENERGY study) is to assess the safety and tolerability of INZ-701 in infants with ENPP1 Deficiency or with ABCC6 Deficiency.
INZ-701 is an ectonucleotide pyrophosphatase/phosphodiesterase 1 (ENPP1) enzyme replacement therapy in development for the treatment of the ultra-rare genetic disorder, ENPP1 Deficiency or with ABCC6 Deficiency.
Study INZ701-104 (the ENERGY study) is a Phase 1b, open-label study to assess the safety, tolerability, pharmacokinetics (PK), and pharmacodynamics (PD) of INZ-701 in infant study participants with ENPP1 Deficiency or ABCC6 Deficiency.
The study will consist of up to a 60-day Screening Period, a 52-week Treatment Period during which study participants will receive INZ-701, an Extension Period during which participants may continue to receive INZ-701 until it is commercially available in the country where the participant resides, or until an alternative study of INZ-701 is available, and an End of Treatment (EOT) visit 30 days after the last dose of INZ-701. Upon treatment discontinuation, participants will continue to be followed for their ongoing disposition for survival outcome at least quarterly through the end of the study.
32 studies on the registry are indexed under Pseudoxanthoma Elasticum; 6 are open to participants now.
This study's enrollment of 9 is below the median of 21 across 16 interventional 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.
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.
Judged by the study doctor to matter for your health or for the study. It is a doctor’s decision, so ask the study team if you are unsure whether something counts.
Malignancy means cancer. Criteria about another or earlier malignancy ask whether you have had a different cancer, usually within a set number of years.
Some are commonly allowed, such as treated skin cancers other than melanoma and early cancers removed completely — check the exceptions this study lists.
A drug or device being studied in a clinical trial.
It may be new, or already approved and being studied for another use, dose or form. Criteria often leave out people who took part in another study of one within a recent period, commonly 30 days or five half-lives.
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.
Clinically significant
Judged by the study doctor to matter for your health or for the study. It is a doctor’s decision, so ask the study team if you are unsure whether something counts.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
Cancer (malignancy)
Malignancy means cancer. Criteria about another or earlier malignancy ask whether you have had a different cancer, usually within a set number of years.
Some are commonly allowed, such as treated skin cancers other than melanoma and early cancers removed completely — check the exceptions this study lists.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
Investigational drug or device
A drug or device being studied in a clinical trial.
It may be new, or already approved and being studied for another use, dose or form. Criteria often leave out people who took part in another study of one within a recent period, commonly 30 days or five half-lives.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
The first 2 study participants will receive 1 dose of 0.2 mg/kg on Day 1 and start at Dose Level A (0.2 mg/kg twice weekly) on Day 8. The Data Review Committee (DRC) comprised of representatives of the Sponsor, the study Investigators, and a physician who is a subject matter expert not affiliated with the study or Sponsor, will review the safety data of the first study participant through Day 8. Contingent upon this review, the Sponsor will decide if additional study participants can begin receiving INZ-701. After the second study participant completes Day 32, the DRC will perform a cumulative review of safety and PK/PD data and will make dosing recommendations, for example, modifying the dose of the ongoing study participants and/or changing the starting dose for future participants. Dose Level A: 0.2 mg/kg twice weekly Dose Level B: 0.6 mg/kg twice weekly Dose Level C: 0.2 mg/kg once weekly Dose Level D: 0.6 mg/kg once weekly Dose Level E: 1.8 mg/kg once weekly
Drug: INZ-701
Recombinant fusion protein that contains the extracellular domains of human ENPP1 coupled with an Fc fragment from an immunoglobulin gamma-1 (IgG1) antibody.
Also known as: (rhENPP1-Fc).
Number of Treatment Emergent Adverse Events (TEAEs)
Treatment-emergent AEs are defined as any AE occurring from the first dose of INZ-701 through 30 days after the last dose of INZ-701.
Time frame: 52 weeks (Treatment Period)
Incidence of Anti-Drug Antibodies (ADA)
For each participant, the presence of ADAs will be assessed and, if present, further evaluation will determine specificity and subtypes.
Time frame: 52 weeks (Treatment Period)
Left Ventricular Ejection Fraction
For each participant, an echocardiogram will be collected, and used to assess heart function. (Including measurement of left ventricular ejection fraction), and to identify any other abnormalities, for example, calcification of heart valves.
Time frame: 52 weeks (Treatment Period)
Change from Baseline in Plasma Inorganic Pyrophosphate (PPi) Levels
For each participant, plasma PPi will be measured via a series of blood samples obtained throughout the study, comparing the participant's baseline value over time.
Time frame: 52 weeks (Treatment Period)
Area under the Plasma Concentration versus Time Curve (AUC) of INZ-701
For each participant, variation of concentration of INZ-701 in the plasma will be measured via a series of blood samples obtained throughout the study, comparing the participant's baseline value over time.
Time frame: 52 weeks (Treatment Period)
Maximum Plasma Concentration (Cmax) of INZ-701
For each participant, the maximum concentration of INZ-701 in the plasma will be measured via a series of blood samples obtained throughout the study, comparing the participant's baseline value over time.
Time frame: 52 weeks (Treatment Period)
ENPP1 Activity
For each participant, the activity of INZ-701 in the serum will be measured via a series of blood samples obtained throughout the study, comparing the participant's baseline value over time.
Time frame: 52 weeks (Treatment Period)
The study was terminated by the sponsor prior to planned completion based on a review of the data across indications and overall program considerations. Study termination was not related to participant safety.
The study was terminated by the sponsor prior to planned completion based on a review of the data across indications and overall program considerations. Study termination was not related to participant safety.
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 ↗
This study is terminated, as verified in Oct 2026. You cannot join it, but the record below documents what was studied.
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Studies of the drug tested here: Efmirenpase alfa