Ebselen (SPI-1005)

How it works

An oral antioxidant (Sound Pharmaceuticals) that mimics glutathione peroxidase to protect the cochlea from oxidative stress and inflammation. Notably, a dedicated tinnitus trial found the 400 mg dose performed worse than placebo on tinnitus outcomes, a cautionary negative result, even though the drug has shown benefit for hearing/speech endpoints in Ménière's disease, where it holds FDA Breakthrough Therapy designation, and the company is now pointing to those hearing results to support a future move into sudden sensorineural hearing loss (Oct 2026). Included as an honest example of a cochlear-protective candidate that did not help tinnitus.

This describes the treatment concept as reported in the cited research: a scientific mechanism, not a guarantee of clinical availability.