A new drug that that inhibits an enzyme known as cyclin-dependent kinase 2 could potentially save the hearing of millions of people.
If CDK2 inhibitors are proven to be an effective treatment for this purpose in humans, it would be very significant. There are no medicines approved by the Food and Drug Administration (FDA) to treat hearing loss at this time.
Around 466 million people worldwide have disabling hearing loss. This includes infection, birth defects, exposure to high decibel noise, and the use of some medicines.
New Drug: Research Serendipity
Researchers originally tested more than 4,000 drugs to find one that would protect inner ear cells from the adverse effects of the chemotherapy drug cisplatin. Cisplatin is known to induce hearing loss in up to 70 percent of patients. Cisplatin induced hearing can be irreversible.
The 4,000 drugs became 10. Of these, three of the most effective drugs were CDK2 inhibitors. Kenpaullone was the most effective of the three.
New Drug: Kenpaullone
Injecting kenpaullone into the middle ear of mice and rats protected the animals from the hearing loss associated with cisplatin. Kenpaullone stopped the CDK2 enzyme from initiating the production of toxins. These toxins are free radicals derived from molecular oxygen and cause a number of adverse effects. Kenpaullone shut down the production of these toxins.
New Drug: Kenpaullone Restores Noise-Related Hearing Loss
Kenpaullone also protected mice from hearing loss caused by noise up to 100 decibels. Given that 100+ decibel noise is so prevalent, kenpaullone could be effective in treating noise-induced hearing loss.
One injection of kenpaullone was so powerful it may be the drug to restore drug and noise induced hearing loss. Further research may yield additional CDK2 drug inhibitors.