DB-OTO (CHORD)
Study sponsor: Regeneron Pharmaceuticals
A multicenter study evaluating a one-time intracochlear OTOF gene therapy in children and infants with congenital hearing loss caused by biallelic OTOF variants.
Plain-language summary
Study overview
- Current study status
- Actively Recruiting
- Who is being studied
- Up to 17 years; cohort-specific
- How treatment is given
- One-time intracochlear injection through the round-window membrane with lateral semicircular canal fenestration
- Study start date
- Jun 27, 2023
Study start date is reported by ClinicalTrials.gov and may differ from the date the first participant received treatment.
Official study record
NCT05788536 · Status shown: Actively Recruiting · Registry information last checked May 5, 2026
Terminology Dictionary
- Target gene
- The gene the treatment is designed to address.
- Gene replacement
- Delivery of a working gene copy intended to restore a missing or impaired function.
- Vector / payload
- The delivery vehicle and the genetic material it carries.
- Promoter
- A DNA control sequence that helps determine where and how strongly the delivered gene is active.
- Cochlear access
- The route used to reach the inner ear and administer the treatment.
- Laterality
- Whether treatment is given to one ear or both ears.
- Phase 1 / 2
- An early human study designed mainly to examine safety, dosing, and initial signs of biological or clinical effect.
- Early clinical
- An early human study for which a formal clinical phase is not assigned or publicly stated.
- Biallelic
- A disease-causing change is present in both copies of a gene.
- Dual vector
- Two delivery vehicles carry separate parts of a gene that is too large to fit into one vehicle.
- Intracochlear
- Delivered into the fluid-filled inner-ear structure involved in hearing.
Who is being studied
The population described by the public study record.
- Study population
- Children and infants with biallelic OTOF-related hearing loss
- Age range
- Up to 17 years; cohort-specific
- Planned enrollment
- 30
- Study regions
- Germany, Japan, Spain, United Kingdom, and United States
This summary describes the study population; it cannot determine whether an individual qualifies.
Therapy design
The genetic treatment and how its activity is controlled.
- Target gene
- OTOF
- Treatment approach
- Gene replacement
- Delivery vector and gene cargo
- Dual AAV1 vectors reconstituting full-length human OTOF transcript variant 5 (hOTOFv5)
- Promoter
- mMyo15, a synthetic hair-cell-specific promoter derived from murine Myosin 15a regulatory sequence
Delivery to the inner ear
How the therapy is administered and whether one or both ears are treated.
- How it is delivered
- One-time intracochlear injection through the round-window membrane with lateral semicircular canal fenestration
- How the inner ear is reached
- Round-window membrane injection with lateral semicircular canal fenestration
- Fenestration
- Yes — lateral semicircular canal (LSCC)
- One or both ears
- Unilateral dose escalation; bilateral expansion
- Study start date
- Jun 27, 2023
Public evidence reviewed
Evidence and limitations
The registry supplies study-conduct fields. Program-specific human and preclinical publications resolve the dual-AAV1 construct, hOTOFv5 payload, mMyo15 promoter, and round-window membrane injection with lateral semicircular canal fenestration.