From the Nov. 15-21 issue of the Puget Sound Business Journal:
Biotech firm seeks treatment for hearing loss

By JOEL OZRETICH
STAFF WRITER
Tiny hairs deep inside the human ear are crucial to how hearing works, but scientists have long believed that once these auditory hair cells are damaged it is impossible to grow them back. But a Seattle-based biotechnology company may have turned that assumption on its ear. Its research could offer hope for people who have permanent hearing damage from repeated exposure to dangerous levels of noise.

Using techniques discovered at the Fred Hutchinson Cancer Research Center, Sound Pharmaceuticals Inc. has shown that it is possible to grow additional auditory hair cells in the inner ears of mice. "The dogma in biology is that cells in your ears and retina just can't regrow," said Matthew Fero, a Hutch researcher who has collaborated with Sound Pharmaceuticals co-founder Jonathan Kil since 1996. "But maybe that dogma can be changed."

Over the next several years, the company hopes to prove that new auditory hair cells can be grown in humans. The prospect helped Sound Pharmaceuticals raise $1 million in the first half of 2002 from private investors and Posco BioVentures of Carlsbad, Calif., the venture capital arm of Korea-based Posco Steel Co. The eight-employee company is now seeking $10 million to continue research on regrowing cells, while also beginning clinical trials of two products - oral and injectable drugs to prevent inner-ear damage before it leads to permanent hearing loss. Posco BioVentures has promised to invest another $2 million in Sound Pharmaceuticals if the company is successful in finding other investors.
"Most people don't think of hearing loss as a major disease, but it's definitely an enormous and major problem," said Glenn Kawasaki, a veteran of several local biotechnology companies and a member of Sound Pharmaceuticals' board. Kawasaki was the first scientist at ZymoGenetics Inc. in the early 1980s.

More than 30 million Americans are exposed to dangerous levels of noise on a regular basis and 10 million people have noise-induced hearing loss, according to the National Institute for Deafness and Communication Disorders.
"It's not just a condition of getting old," Kawasaki said.

Sound Pharmaceuticals was founded last year by Kil and former University of Washington researcher Eric Lynch, who left their previous company, Otogene AG, after a disagreement with the company's board in Germany. Sound Pharmaceuticals later licensed Otogene's technology. Now, the company plans to build upon several years of collaboration between Otogene and the Hutch to move the technology forward.

Sound Pharmaceuticals initially plans to focus on drugs to prevent hearing loss. The company will target U.S. military personnel, who are often exposed to high levels of noise from firearms and jet planes, and cancer patients, who often experience hearing loss after treatment with certain chemotherapy drugs. The company's two leading drugs are based on an existing compound, ebselen, which has been shown to protect auditory hair cells in mice exposed to high levels of noise or cancer drugs that cause hearing damage. Ebselen is approved in Japan to treat stroke patients.

Sound Pharmaceuticals has filed for patents using the pill form of ebselen, which is currently available, to prevent noise-induced hearing loss. The company estimates that the market for ebselen as a hearing protection drug is more than $200 million, based on the 200,000 U.S. military personnel that are exposed to high levels of noise each year. Sound Pharmaceuticals expects to begin clinical trials of ebselen for hearing protection by the fourth quarter of 2003.
The company's next drug candidate is an injectable form of ebselen, which could be used to treat cancer patients to prevent hearing loss.

But Sound Pharmaceuticals' largest market could be the regrowth of auditory hair cells, which the company estimates at more than $1 billion. "I think the otoprotection (hearing protection) and chemoprotection products are very low risk," Kawasaki said. "But the real home run will be restoring hearing." The science behind regrowing auditory hair cells, however, is much earlier stage. So far, Kil and researchers at Fred Hutch have been able to show that auditory hair cells can proliferate in mice that lack the p27 gene, which stops auditory hair-cell growth. But those hair cells have not been shown to function properly or improve hearing in live animals. "Regenerating hearing, I think, is much more rocket science," said Fero. "There's a whole series of obstacles that need to be overcome and all of them are significant. Cells have to attach to neural synapses and have to be able to function normally." Still, he said, "It's exciting, because some of the dogma has already been overcome."

Reach Joel Ozretich at 206-447-8505 ext. 107 or jozretich@bizjournals.com.