NCT05788536 · Regeneron Pharmaceuticals
A Study of DB-OTO, an Adeno-Associated Virus (AAV) Based Gene Therapy, in Children/Infants With Hearing Loss Due to Otoferlin Mutations
(CHORD)
What this study is about
Regeneron is conducting a study of an experimental new drug called DB-OTO. DB-OTO is a gene therapy that is being developed to treat children who have hearing loss due to changes in the otoferlin gene.
View original scientific description
Regeneron is conducting a study of an investigational new drug called DB-OTO. DB-OTO is a gene therapy that is being developed to treat children who have hearing loss due to changes in the otoferlin gene.
Interventions
GENETIC
DB-OTO
Administered per the protocol
Primary outcome measures
Incidence and severity of Treatment-Emergent Adverse Events (TEAEs)
Time frame: Up to week 104
Achievement of a hearing sensitivity threshold of ≤70 dB assessed by average Pure Tone Audiometry (PTA)
Time frame: Up to week 104
Who can participate
This study lists these criteria on ClinicalTrials.gov. A study coordinator reviews eligibility during screening — this page does not determine whether you qualify.
Inclusion criteria
- Willingness to provide written informed consent (by at least one parent/legal guardian for pediatric participants, and with participant to provide assent, when applicable, or by the adult participant) and willingness to comply with trial protocol
- Willingness to consent to genetic testing for the participant (by at least one parent/legal guardian for pediatric participants, and with participant to provide assent, when applicable, or by the adult participant) in order to evaluate a panel of hearing loss-related genes
- Willingness to consent to vaccinations for the participant (by at least one parent/legal guardian for pediatric participants, and with participant to provide assent, when applicable, or by the adult participant) in accordance with the country-specific, age-appropriate immunization schedule, as described in the protocol
- Participant able to perform all necessary assessments to qualify for enrollment and dosing in the corresponding cohort at the time the participant or parent/legal guardian signing the informed consent form (and participant providing assent, when applicable)
- Presence of biallelic, likely pathogenic or pathogenic OTOF variants
- No clinically significant laboratory findings on clinical laboratory tests at time of Screening as described in the protocol
- Audiological Criteria:
- Investigator diagnoses the participant with profound sensorineural hearing loss (SNHL; \>90 dB HL) based on behavioral and physiologic measurements (ABR) of inner ear function
- Outer hair cell presence is confirmed via presence of otoacoustic emissions (≥6 dBSNR) at ≥3 frequencies from 1 to 8 kHz in the ear(s) to be infused with DB-OTO. Alternatively, for participants \>24 months of age, outer hair cell presence can be confirmed via presence of the cochlear microphonic in the ear(s) to be infused with DB-OTO.
- No evidence from measures of hearing loss that show a dependence on body temperature
- From study start and for the duration of the short-term follow-up period (48 weeks): Female participants of childbearing potential and fertile males, must agree to use highly effective contraception. Female participants must agree not to become pregnant. Fertile male participants must agree not to father a child or donate sperm, for 48 weeks and in cases of early withdrawal, for at least 12 months after DB-OTO administration. Key
Exclusion criteria
- History of prior treatment with gene therapy
- Surgical anatomy that would preclude or meaningfully impact the planned surgical approach as indicated by medical imaging (eg, Computed Tomography \[CT\] or Magnetic Resonance Imaging \[MRI\]) in the ear(s) to be infused with DB-OTO
- History or presence of other permanent or untreatable hearing loss conditions
- Prior or current history of malignancies
- Prior or current history of meningitis
- History or presence of cochlear implants in the ear(s) to be infused with DB-OTO
- History of risk factor(s) for auditory neuropathy not caused by OTOF pathogenic variants including but not limited to: prematurity, low birth weight, hyperbilirubinemia, Neonatal Intensive Care Unit (NICU) admission, and/or low Apgar scores as described in the protocol Note: Other protocol-defined inclusion/exclusion criteria apply
Where
- Los Angeles, California
- San Diego, California
- Jacksonville, Florida
- Orlando, Florida
- Boston, Massachusetts
- New York, New York
- Cincinnati, Ohio
- Seattle, Washington
- Milwaukee, Wisconsin
Related conditions & keywords
Frequently asked questions
What is a clinical trial?
A clinical trial is a research study that tests new medical treatments, drugs, devices, or procedures to determine their safety and effectiveness. Trials are carefully designed and monitored to protect participants while advancing medical knowledge.
Is it safe to participate?
Clinical trials follow strict safety guidelines and ethical standards. Trials must be reviewed and approved, and participants are closely monitored by medical professionals throughout the study. You can withdraw at any time if you choose.
Will I be compensated?
Many clinical trials offer compensation for your time, travel expenses, and inconvenience. The specific compensation varies by study and will be discussed during the screening process. All study-related medical care is typically provided at no cost to participants.
Will I receive a placebo instead of treatment?
When effective treatment exists, participants typically receive either the standard treatment plus the study intervention, or the standard treatment plus placebo. You would not be denied effective care. Placebos are primarily used when no proven treatment is available, or in addition to standard care. Your trial consent form will clearly explain what treatments you may receive.
Can I leave a trial if I change my mind?
Absolutely. Participation in clinical trials is completely voluntary. You have the right to withdraw from the study at any time, for any reason, without penalty or loss of benefits to which you are otherwise entitled.
How long does a clinical trial last?
Trial duration varies widely depending on the study design and purpose. Some trials last just a few weeks, while others may continue for months or years. The study coordinator will provide specific timeline information during your screening call.
Data: ClinicalTrials.gov · synced Aug 5, 2026 · Source of record for eligibility and locations