From their press release:Otonomy may have put themselves in a cannibalization scenario with OTO-313 for tinnitus. If it turns out OTO-413 treats tinnitus as a symptom of synaptopathy; it reduces the need for a OTO-313 which might be a problem.
One might hypothesize that if FX-322 does indeed produce a significant reduction in TFI by creating new hair cells and thereby improving hearing; it's pretty likely that reconnecting synapses and improving hearing may also have a noticeable affect in tinnitus.
Just one theory.
"We believe that gacyclidine can reduce the severity of tinnitus symptoms following cochlear injury by decreasing the over-activation of damaged auditory nerve fibers in the cochlea and their connections."
With that in mind, yes OTO-413 would treat AN underlying cause of what they are trying to address with OTO-313. But they didn't select for synaptopathy in their trial so clearly they don't believe it would only work for cases where synaptopathy is the cause of the over-excitation.
Here was their inclusion criteria:
- Subject's tinnitus is likely of cochlear origin, e.g., associated with sensorineural hearing loss; acute hearing loss from noise trauma, barotrauma, or traumatic cochlear injury (acute acoustic trauma, blast trauma, middle ear surgery, inner ear barotrauma); age-related hearing loss; resolved otitis media; ototoxic drug exposure.