Ebselen, a synthetic drug molecule that mimics glutathione peroxidase (GPx), a critical enzyme in the inner ear that protects it from damage caused by loud sounds or noise

Stem cell and gene therapy
Hair cell regeneration using stem cell and gene therapy is years or decades away from being clinically feasible. However, studies are currently underway on the subject, with the first FDA-approved trial beginning in February 2012. Sudden sensorineural hearing loss
Sudden sensorineural hearing loss (SSHL or SSNHL), commonly known as sudden deafness, occurs as an unexplained, rapid loss of hearing—usually in one ear—either at once or over several days. Nine out of ten people with SSHL lose hearing in only one ear. It should be considered a medical emergency. Delaying diagnosis and treatment may render treatment less effective or ineffective. Experts estimate that SSHL strikes one person per 100 every year, typically adults in their 40s and 50s. The actual number of new cases of SSHL each year could be much higher because the condition often goes undiagnosed. Presentation
Many people notice that they have SSHL when they wake up in the morning. Others first notice it when they try to use the deafened ear, such as when they use a phone. Still others notice a loud, alarming "pop" just before their hearing disappears. People with sudden deafness often become dizzy, have ringing in their ears (tinnitus), or both. Diagnosis
SSHL is diagnosed via pure tone audiometry. If the test shows a loss of at least 30 dB in three adjacent frequencies, the hearing loss is diagnosed as SSHL.
The base of the basilar membrane is narrow and stiff, resulting in it responding best to high frequency sounds. The apex of the basilar membrane is wider and much less stiff in comparison to the base, causing it to respond best to low frequencies.This selectivity to certain frequencies can be illustrated by neural tuning curves. These demonstrate the frequencies a fiber responds to, by showing threshold levels (dB SPL) of auditory nerve fibers as a function of different frequencies. This demonstrates that auditory nerve fibers respond best, and hence have better thresholds at the fibers characteristic frequency and frequencies immediately surrounding it. The basilar membrane is said to be ‘sharply tuned’ due to the sharp ‘V’ shaped curve, with its ‘tip’ centered at the auditory fibers characteristic frequency. This shape shows how few frequencies a fiber responds to. If it were a broader ‘V’ shape, it would be responding to more frequencies (See Figure 4). IHC vs OHC hearing loss
A normal neural tuning curve is characterised by a broadly tuned low frequency ‘tail’, with a finely tuned middle frequency ‘tip’. However, where there is partial or complete damage to the OHCs, but with unharmed IHCs, the resulting tuning curve would show the elimination of sensitivity at the quiet sounds. I.e. where the neural tuning curve would normally be most sensitive (at the ‘tip’) (See Figure 5).Where both the OHCs and the IHCs are damaged, the resulting neural tuning curve would show the elimination of sensitivity at the ‘tip.