Both sisomicin and netilmicin are aminoglycosides similar to gentamicin, but only netilmicin offers any advantage over gentamicin and has been used regularly.

doi.org/10.1201/9781315152110, hdl.handle.net/1765/112315
Department of Medical Microbiology and Infectious Diseases

Mouton, J.W. (Johan W.). (2017). Sisomicin and netilmicin. In Kucers the Use of Antibiotics: A Clinical Review of Antibacterial, Antifungal, Antiparasitic, and Antiviral Drugs, Seventh Edition (pp. 1028–1038). doi:10.1201/9781315152110