iECURE Receives FDA Fast Track Designation for ECUR-506 for the Treatment of Neonatal Onset Ornithine Transcarbamylase (OTC) Deficiency

iECURE, Inc., a gene editing company focused on the development of mutation-agnostic in vivo gene insertion, or knock-in, editing therapies for the treatment of liver disorders with significant unmet need, announced today that it has received Fast Track designation from the U.S. Food and Drug Administration (FDA) for ECUR-506, the company's in vivo gene insertion program designed to treat neonatal onset Ornithine Transcarbamylase (OTC) deficiency.

The Fast Track designation is designed to facilitate the development and expedite the review of therapeutics to treat serious conditions that fill an unmet medical need. Therapeutics that receive Fast Track designation are eligible for more frequent meetings with and written communication from FDA to discuss the therapeutic's development plan and ensure collection of appropriate data to support potential approval of the therapeutic. Provided relevant criteria are met, programs with Fast Track designation are eligible for accelerated approval and priority review as well.

"Receipt of Fast Track designation from the FDA is a validation of the severe unmet need for patients with neonatal onset OTC deficiency and a testament to the preclinical data generated to date for ECUR-506," said Joe Truitt, Chief Executive Officer of iECURE. "The benefits of Fast Track designation may accelerate our ability to get ECUR-506 into physicians' hands, which is incredibly important when every second counts for these babies."

ECUR-506 previously received Rare Pediatric Disease and Orphan Drug designations from the FDA, and Orphan designation from the European Commission for the treatment of OTC deficiency.

iECURE's OTC-HOPE study, a Phase 1/2 first-in-human study in newborn males with genetically confirmed neonatal onset OTC deficiency, is open for enrollment at the Great Ormond Street Hospital for Children in the United Kingdom. In addition, trial sites in the United States and Australia are activating and will be enrolling later this year. The study is designed primarily to assess the safety and tolerability of ECUR-506 following intravenous administration of a single dose. Secondary objectives are to assess the pharmacokinetics and efficacy of ECUR-506. In addition, exploratory endpoints will assess disease-specific biologic markers, developmental milestones and quality of life.

About ECUR-506

iECURE's approach to gene editing for its initial programs, including OTC deficiency, relies on the delivery of two adeno-associated virus (AAV) capsids, each carrying different payloads. ECUR-506 comprises two vectors, an ARCUS® nuclease vector targeting gene editing in the well-characterized PCSK9 gene locus and a donor vector that inserts the desired functional OTC gene. iECURE has licensed the ARCUS nuclease for ECUR-506 from Precision BioSciences.¹ The cut in the PCSK9 site serves as the insertion site for the OTC gene, providing a potential path to permanent expression of a healthy gene. ECUR-506 is being studied in the OTC-HOPE study, the first clinical meganuclease-based in vivo gene insertion program. The ECUR-506 program is the first in vivo gene insertion program to be cleared in the U.S. for study in infants, and it represents the first time that the ARCUS® nuclease has been used to provide an in vivo insertion point for a functional gene in the clinic.

About the OTC-HOPE Study

The OTC-HOPE study is a Phase 1/2 first-in-human clinical trial of ECUR-506 in newborn males with genetically confirmed neonatal onset OTC deficiency and will test differing dose levels of ECUR-506. The study is enrolling newborn males up to seven months of age who are diagnosed with severe neonatal onset OTC deficiency and meet certain other criteria. The primary objective is to assess the safety and tolerability of intravenous administration of a single dose of ECUR-506. It will also assess the pharmacokinetics and efficacy of ECUR-506 administration and the potential effects of ECUR-506 on disease-specific biologic markers, developmental milestones and quality of life. For more information, visit https://otc-hope.com/.

About iECURE

iECURE is a clinical-stage gene editing company focused on developing therapies that utilize mutation-agnostic in vivo gene insertion, or knock-in, editing for the treatment of liver disorders with significant unmet need. We believe our approach has the potential to replace and restore the function of a dysfunctional gene, regardless of mutation, by knocking-in a healthy copy of that gene to offer durable gene expression and long-term, potentially curative, therapeutic benefit. Our management team has extensive experience in executing global orphan drug and gene therapy clinical trials and successfully commercializing multiple products. We intend to leverage our team's core strength in research and development strategy to identify what we believe to be the most suitable target and modality for our product candidates to address particular liver diseases. We are collaborating with the University of Pennsylvania's Gene Therapy Program (GTP) led by James M. Wilson, M.D., Ph.D., to utilize GTP's world-class preclinical and translational expertise and infrastructure, which has helped generate our initial pipeline of potential product candidates. For more information, visit https://iecure.com and follow on LinkedIn.

About Precision BioSciences & ARCUS®

Precision BioSciences, Inc. is an advanced gene editing company dedicated to improving life (Nasdaq: DTIL) with its novel and proprietary ARCUS® genome editing platform that is designed to differ from other technologies in the way it cuts, its smaller size, and its simpler structure. Key capabilities and differentiating characteristics may enable ARCUS nucleases to drive more intended, defined therapeutic outcomes. Using ARCUS, Precision's pipeline is comprised of in vivo gene editing candidates designed to deliver lasting cures for the broadest range of genetic and infectious diseases where no adequate treatments exist. For more information about Precision BioSciences, visit www.precisionbiosciences.com.

[1] iECURE has licensed the ARCUS® nuclease from Precision BioSciences for four gene insertion programs including OTC, CTLN1 and PKU.