ECUR-506 / iECURE - LARVOL DELTA

Decreased rate of hyperammonemic crises in infants with neonatal-onset OTC deficiency post ECUR-506 administration (SSIEM 2026) - P3 | "ECUR-506 was associated with reduced HAC frequency without increased standard-of-care interventions. These preliminary findings suggest that ECUR-506 may be a promising approach to improve metabolic control in an at-risk patient population."

First-in-human • Genetic Disorders • Metabolic Disorders

OTC-HOPE: An Open-label Study to Investigate ECUR-506 in Male Babies Less Than 9 Months of Age With Neonatal Onset OTC Deficiency (clinicaltrials.gov) - P3 | N=20 | Recruiting | Sponsor: iECURE, Inc. | Phase classification: P1/2 ➔ P3

First-in-human • Phase classification • Genetic Disorders • Metabolic Disorders

Decreased rate of hyperammonemic crises in infants with neonatal-onset OTC deficiency post ECUR-506 administration: preliminary update from the OTC-HOPE study. (ASGCT 2026) - P1/2 | "Administration of ECUR-506 was associated with a reduction of HACs from average rates of 4/year to 0.6/year, with no increase in other standard of care therapies. These preliminary findings from the ongoing OTC-HOPE study suggest that ECUR- 506 may be a promising approach to improve metabolic control and decrease HACs in an at- risk patient population."

First-in-human • Genetic Disorders • Metabolic Disorders • PCSK9

OTC-HOPE: An Open-label Study to Investigate ECUR-506 in Male Babies Less Than 9 Months of Age With Neonatal Onset OTC Deficiency (clinicaltrials.gov) - P1/2 | N=20 | Recruiting | Sponsor: iECURE, Inc. | Trial completion date: Sep 2026 ➔ Dec 2027 | Trial primary completion date: Sep 2026 ➔ Dec 2027 | Active, not recruiting ➔ Recruiting

Enrollment open • First-in-human • Trial completion date • Trial primary completion date • Genetic Disorders • Metabolic Disorders

OTC-HOPE: An Open-label Study to Investigate ECUR-506 in Male Babies Less Than 9 Months of Age With Neonatal Onset OTC Deficiency (clinicaltrials.gov) - P1/2 | N=8 | Active, not recruiting | Sponsor: iECURE, Inc. | Recruiting ➔ Active, not recruiting

Enrollment closed • First-in-human • Genetic Disorders • Metabolic Disorders

iECURE Receives FDA Regenerative Medicine Advanced Therapy (RMAT) Designation for ECUR-506 for Neonatal Onset Ornithine Transcarbamylase (OTC) Deficiency (Businesswire) - "iECURE’s receipt of these regulatory designations is supported by encouraging clinical data from the ongoing OTC-HOPE clinical study, including a complete clinical response observed in the first infant treated with ECUR-506."

FDA event • Genetic Disorders

OTC-HOPE: An Open-label Study to Investigate ECUR-506 in Male Babies Less Than 9 Months of Age With Neonatal Onset OTC Deficiency (clinicaltrials.gov) - P1/2 | N=8 | Recruiting | Sponsor: iECURE, Inc. | N=13 ➔ 8

Enrollment change • Genetic Disorders • Metabolic Disorders

Cell-Based Potency Assay for ECUR-506: A Groundbreaking Investigational Therapy for the Treatment of Neonatal Ornithine Transcarbamylase (OTC) Deficiency (ASGCT 2025) - "Validating the physiological activity of the drug product via cell-based potency assay is critical in demonstrating the assay is accurate and reliable in its ability to ensure manufactured vector lots are comparable, and the assay is representative of the mechanism of action. Although evaluating gene activity in vitro can pose difficulties, managing a drug involving double AAV and integration issues may prove even more complex. The developed assays provide robust methods to assess the functional potency and genomic integration of iECURE's gene insertion therapy for OTC deficiency."

Late-breaking abstract • CNS Disorders • Epilepsy • Genetic Disorders • Metabolic Disorders • Vascular Neurology

Initial clinical results from OTC-HOPE, the first in vivo , liver directed, AAV-mediated gene insertion study in neonatal OTC deficiency: complete clinical response observed in first male infant to receive ECUR-506 and complete 24-week Phase 1/2 study (ASGCT 2025) - P1/2 | "These are data from the first infant to undergo in-vivo, liver directed, AAV-mediated gene insertion and to complete the OTC-HOPE clinical trial. The observed increase in BUN and urinary nitrogen along with normal mean ammonia levels and increased protein intake following ECUR-506 administration in conjunction with scavenger medication discontinuation are suggestive of increased nitrogen flux through the urea cycle and restoration of at least partial functional hepatic OTC enzyme activity. The complete clinical response, as defined in the OTC-HOPE clinical protocol, achieved in this patient support the continued evaluation of low dose ECUR-506 (1.3 x1013GC/kg) in the clinical trial."

P1/2 data • Preclinical • Genetic Disorders • Infectious Disease • Inflammation • PCSK9

OTC-HOPE: The first in vivo, liver directed, AAV-mediated, gene insertion clinical trial in infants (ASGCT 2025) - P1/2 | "These data are from the first infant to receive an in vivo , liver-directed, gene insertion, investigational product (ECUR-506) and complete the OTC-HOPE study. The observed safety profile and complete clinical response, by study definition, support the continued evaluation of ECUR-506 in the OTC-HOPE study."

Preclinical • Gene Therapies • Genetic Disorders • PCSK9

iECURE to Present Initial OTC-HOPE Clinical Data of ECUR-506 in Ornithine Transcarbamylase Deficiency at Upcoming Medical Meetings (Businesswire) - "iECURE...announced today approval from the U.K. Medicines & Healthcare products Regulatory Agency (MHRA) of the company’s Clinical Trial Authorisation application (CTA) to expand the OTC-HOPE study into the U.K. The OTC-HOPE study is investigating ECUR-506, an investigational gene editing-based therapy, for the treatment of Ornithine Transcarbamylase (OTC) deficiency in infants."

MHRA approval • Genetic Disorders

iECURE to Present Initial Data from Phase 1/2 OTC-HOPE Clinical Trial in Ornithine Transcarbamylase Deficiency at ACMG Annual Clinical Genetics Meeting (Businesswire) - "iECURE, Inc...today announced that initial data from the Phase 1/2 OTC-HOPE clinical trial evaluating in vivo gene editing candidate ECUR-506 in neonatal onset ornithine transcarbamylase (OTC) deficiency will be presented at the 2025 American College of Medical Genetics and Genomics (ACMG) Annual Clinical Genetics Meeting taking place March 18-22, 2025 in Los Angeles."

P1/2 data • Genetic Disorders

iECURE Reports Complete Clinical Response in First Infant Dosed with its In Vivo Gene Editing Candidate ECUR-506 in an Ongoing Phase 1/2 Clinical Trial in Ornithine Transcarbamylase (OTC) Deficiency (Businesswire) - P1/2 | N=13 | OTC-HOPE (NCT06255782) | Sponsor: iECURE, Inc. | "The first infant dosed with ECUR-506 was initially diagnosed with neonatal onset OTC deficiency following a HAC during the first week of life, and he was stabilized with hemodialysis and managed with standard of care ammonia scavenger medication and protein restriction...At 3.5 months of age, while on a protein restricted diet and on scavenger medicine, the participant experienced a breakthrough HAC. At 6.5 months of age, the participant received a single infusion of the lowest dose (1.3 x 1013 GC/kg) of ECUR-506, which was generally well tolerated...On the basis of reduced serum glutamine levels, ammonia scavenger medication weaning was initiated with complete discontinuation achieved at 12 weeks post-ECUR-506 dosing...Dosing of cohort 1 (Low Dose) continues and the complete six-month data readout for all patients is anticipated in the first half of 2026."

P1/2 data • Genetic Disorders

An Open-label Study to Investigate ECUR-506 in Male Babies Less Than 9 Months of Age With Neonatal Onset OTC Deficiency (OTC-HOPE) (clinicaltrials.gov) - P1/2 | N=13 | Recruiting | Sponsor: iECURE, Inc. | Active, not recruiting ➔ Recruiting

Enrollment open • Genetic Disorders • Metabolic Disorders

An Open-label Study to Investigate ECUR-506 in Male Babies Less Than 9 Months of Age With Neonatal Onset OTC Deficiency (OTC-HOPE) (clinicaltrials.gov) - P1/2 | N=13 | Active, not recruiting | Sponsor: iECURE, Inc. | Recruiting ➔ Active, not recruiting

Enrollment closed • Genetic Disorders • Metabolic Disorders