The goal of this clinical trial is to learn about the effects of drug SPI-1005 in adults receiving a cochlear implant with a long electrode array (FLEX26 or greater) from MED-EL Cochlear Implant Systems into one ear.

The main question this clinical trial aims to answer is: Is drug SPI-1005 safe and well-tolerated in adults receiving a cochlear implant, and/or what medical problems might participants experience when taking drug SPI-1005?

The clinical trial will also measure the effects of SPI-1005 on hearing, word recognition, speech discrimination, tinnitus, and vertigo outcomes after receiving a cochlear implant. The purpose for this and future clinical trials is to learn whether SPI-1005 can prevent or treat these side effects after receiving a cochlear implant.

Participants will take drug SPI-1005 or placebo (a look-alike substance that contains no drug) for 6 months, starting 2 days before receiving the cochlear implant. There are 5 required in-clinic visits over 6 months for audiology and other tests.

The effects of SPI-1005 will be compared to the placebo (the look-alike substance that contains no drug) to study what effects SPI-1005 might have.

Inclusion Criteria:

• Adults who are ≥18 years of age at time of consent.

• Post-lingual, bilateral, moderate to profound sensorineural hearing loss scheduled to receive a long electrode array (FLEX26 or greater) from MED-EL Cochlear Implant Systems into one ear.

• Air conduction thresholds (decibel hearing loss, dB HL) at baseline in the ear scheduled to receive the cochlear implant:

  • ≤70 dB HL at 125, 250, and 500 Hz; AND
  • ≥70 dB HL at 2000, 4000, and 8000 Hz.

• Type A (including As and Ad) tympanogram at baseline in the ear scheduled to receive the cochlear implant.

• Willing and able to provide informed consent and to perform all behavioral tests as specified per-protocol, including pre-specified reproductive requirements.

Exclusion Criteria:

• Current, or within 60 days prior to study consent, use of IV ototoxic medications such as chemotherapy including cisplatin, carboplatin, or oxaliplatin; aminoglycoside antibiotics including gentamicin, amikacin, tobramycin, kanamycin, or streptomycin; or loop diuretics including furosemide.
• Participation in another investigational drug or device study within 90 days prior to study consent.
• Female patients who are pregnant or breastfeeding.
• Moderate or severe hepatic impairment using Child-Pugh Score (>6 points).
• No measurable air conduction response at three or more consecutive test frequencies (e.g., 2000, 4000 and 8000 Hz) at baseline in the ear scheduled to receive the cochlear implant.
• No middle ear mobility (Type B tympanogram) or abnormal middle ear pressure (exceeds -150 to +50 range).