Kyoto, Japan — A new treatment has been developed for sudden sensorineural hearing loss (SSHL), a condition that causes deafness in an estimated 40,000 Americans each year, usually in early middle-age. Researchers from Kyoto University writing in the open access journal BMC Medicine describe the positive results of a preliminary trial of insulin-like growth factor 1 (IGF1), applied as a topical gel.

Takayuki Nakagawa, MD, PhD, of the Department of Otolaryngology, Head and Neck Surgery of Kyoto University Hospital and a team of researchers tested the gel in 25 patients whose SSHL had not responded to the normal treatment of systemic gluticosteroids.

"The results indicated that the topical IGF1 application using gelatin hydrogels was safe, and had equivalent or superior efficiency to the hyperbaric oxygen therapy that was used as a historical control," Nakagawa said. "This suggests that the efficacy of topical IGF1 application should be further evaluated using randomized clinical trials."

At 12 weeks after the test treatment, 48% of patients showed hearing improvement, and the proportion increased to 56% at 24 weeks. No serious adverse events were observed. This is the first time that growth factors have been tested as a hearing remedy.

"Although systemic glucocorticoid application results in hearing recovery in some patients with SSHL," Nakagawa said, "approximately 20% show no recovery. Topical IGF1 application using gelatin hydrogels is well tolerated and may be efficacious for these patients."

SOURCE: BioMed Central