NEW YORK – Gene editing company iEcure has received permission from the US Food and Drug Administration to begin testing its investigational gene therapy ECUR-506 in patients with ornithine transcarbamylase (OTC) deficiency.
The FDA's clearance of iEcure's investigational new drug application will allow the Philadelphia-based firm to begin enrolling patients at US sites in the OTC-HOPE trial of ECUR-506. The study, which is already cleared to begin enrollment in the UK and Australia, will involve newborn males with a genetically confirmed diagnosis of OTC deficiency, which is caused by mutations in the OTC gene and leads to an overabundance of ammonia in the blood.
Newborns with OTC deficiency can initially be lethargic, irritable, and refuse to eat, but as the condition worsens, patients start to seize, have diminished muscle tone, and experience liver and respiratory problems. At present, a liver transplant is the only curative option, which can be risky and requires patients to receive immunosuppressants to prevent organ rejection.
In the Phase I/II OTC-HOPE study, iEcure aims to assess the safety and tolerability of ECUR-506 after a single, intravenous dose. Researchers will also track the gene therapy's pharmacokinetics, its initial efficacy, and its impact on exploratory endpoints such as disease-specific biological markers, developmental milestones, and quality of life.
"We are working diligently to open [clinical trial] sites so we can start enrolling patients for dosing," iEcure CEO Joe Truitt said in a statement. "The trial will be accepting eligible baby boys with neonatal-onset OTC deficiency from all over the world, and we hope to see positive safety data and indications of efficacy with this trial."
iEcure touted ECUR-506 as the first in vivo gene insertion program to be cleared for testing in infants in the US. ECUR-506 was developed in the lab of James Wilson, director of the University of Pennsylvania's gene therapy program. UPenn and Wilson hold equity interests in iEcure.
ECUR-506 uses adeno-associated viruses to deliver two payloads: a working copy of the OTC gene and a gene that encodes for the editing enzyme that allows the functional OTC gene to be inserted in the correct location in the PCSK9 gene locus. iEcure has licensed the ARCUS nuclease from Precision Biosciences and is using it to make cuts at the PCSK9 gene insertion site where the OTC gene is delivered. This program represents the first use of the ARCUS nuclease for in vivo insertion of a functional gene in a clinical trial, the company said.