Otoferlin [1] uses calcium as a cofactor. These mutations happen for a reason. The enzyme is not only located in the ear, but also in the brain and bone marrow [2].
Will there be repercussions if the virus leaves the local area when the therapy is injected?
These OTOF mutation have their highest expression in the Turkish population. Many people with other variations of this gene only experience deafness when they have a fever[3]. So in my opinion, I would like to see ten year outcomes before celebrating.
[1] https://www.uniprot.org/uniprotkb/Q9HC10/entry
[2] https://www.proteinatlas.org/ENSG00000115155-OTOF/tissue
[3] https://www.frontiersin.org/journals/cell-and-developmental-...