New Study-Inozyme

PI: Brian Bush

The Fetal Heart Society is pleased to announce a new study open for enrollment of Generalized Arterial Calcification of Infancy (GACI) patients. Please see the information below:

Phase 1/2 study in infants with Generalized Arterial Calcification of Infancy

Generalized Arterial Calcification of Infancy (GACI) is a rare genetic disease characterized by abnormal cardiovascular mineralization which can be detected on prenatal or postnatal ultrasound. Complications associated with GACI include nonimmune hydrops or pericardial effusion in utero, and heart failure, hypertension, or pulmonary hypertension in neonates. GACI is associate with ~50% infant mortality and there are no approved treatment options. The ENERGY study will evaluate the safety and tolerability of an ENPP1 enzyme replacement therapy in infants with GACI.

The ENERGY Study: An Open-Label Study to Evaluate the Safety, Tolerability, Pharmacokinetics, and Pharmacodynamics of INZ-701 in Infant Subjects with Ectonucleotide Pyrophosphatase/ Phosphodiesterase 1 (ENPP1) Deficiency

ENPP1 deficiency is an ultra-rare genetic disorder with no available treatment and a high infantile mortality rate. This deficiency results from a mutation that inactivates the ENPP1 gene. ENPP1 is responsible for the hydrolysis of adenosine triphosphate (ATP) to generate adenosine monophosphate (AMP) and inorganic pyrophosphate (PPi). Patients with ENPP1 deficiency have abnormally low levels of PPi, which is a potent inhibitor of hydroxyapatite crystal deposition. As a result, patients suffering from the disease can develop generalized arterial calcification and mineralization of other tissues. INZ-701, recombinant human ENPP1 fused to the Fc fragment of IgG1 (rhENPP1-Fc), is an enzyme replacement therapy (ERT) in development for the treatment of ENPP1 Deficiency. The ENERGY open-label study aims to evaluate the safety and efficacy of INZ-701 in treating ENPP1 deficiency.

Study Outline


Approximately 5 sites are planned to participate in the study. Currently two sites are open and accepting patient enrollment.

For clinicians who have identified potential infants for the study, please reach out to a site at the contact information below:

1.     Children’s Hospital of Philadelphia

        Contact: Maximillian Krumpholz, (267)432-0511,

                         Rachel Walega (267)586-5969,

2.     Boston Children’s Hospital

         Contact: Alayna Dutcher (617)355-0741,

               Andrea Hale, RN, MHP (617)919-2867,


Up to 8 patients aged ≥1 month to <1 year with a confirmed post-natal molecular diagnosis of ENPP1 Deficiency (ie, homozygous or compound heterozygous biallelic ENPP1 mutations) are eligible to participate in this study if all other eligibility criteria are met. Written or electronic consent must be provided by the caregiver(s).


The primary objective of the study is to assess the safety and tolerability of INZ-701. The secondary objective of the study is to study the pharmacokinetics and pharmacodynamics of the study. Further exploratory objectives include assessing survival, changes in physical growth, infant development and functional performance, change in biomarkers related to bone and mineral metabolism, and healthcare utilization.

Anticipated Study Duration: The study will consist of a 60-day Screening Period to determine subject eligibility and establish Baseline for assessments, a 52-week Treatment Period during which subjects will receive INZ-701 treatment, an Extension Period during which subjects may continue to receive INZ-701, and an End of Treatment (EOT) visit 30 days after the last dose of INZ-701.

To join this study, please email

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