University’s hearing-impairment prevention drug in testing stage

By Matt Daray

Future men and women of the armed services may thank SIU for the prevention of hearing loss in active duty.

The university’s School of Medicine in Springfield developed a drug called D-methionine, which will prevent and possibly reverse noise-induced hearing loss. The drug has progressed far enough that the U.S. Department of Defense Army Research and Material Command Branch provided a $2.5 million grant to support a Phase 3 clinical trial at the Fort Jackson, S.C., military base to test the drug’s effectiveness.

Kathleen Campbell, a professor of otolaryngology, director of audiology research and the drug’s creator, said she is excited to have it nearing Federal Drug Administration approval.


“It is a great joy to finally be reaching the stage where I can actually start to help the patient populations that started me down this path so many years ago,” she said. “Very few drugs discovered on the bench get this far.”

D-methionine is a component of protein mainly found in fermented proteins such as cheese and yogurt. It provides materials for the human body to form antioxidants. She said this process helps the body produce glutathione, which helps increase cellular defense. That defense, she said, is what would prevent the hearing loss.

Campbell said she got the idea during her several years as a clinical audiologist. She got frustrated at her inability to help patients get their normal hearing back. She said she used research and her own knowledge to find an oral medication that could prevent or even reverse hearing loss, and she found D-methionine to be the most effective.

D-methionine is slated for military use, Campbell said, but the drug may one day be available to the public as well.

“While I am first developing it to protect our troops with support from the U.S. Department of Defense, the goal is to have it available to prevent or reverse noise-induced hearing loss within a day or so of noise exposure in multiple populations worldwide,“ she said.

Chancellor Rita Cheng said the drug is important for Campbell as well as the university because it will bring attention to the university’s medical school.

“(Kathleen has) been engaged in this project for a long time. … Getting to Phase 3 is a very significant accomplishment for her, and it brings so much positive attention for her, her hearing research colleagues and to SIU.”


Cheng said the drug also shows the university’s dedication to veterans and the armed forces as a whole.

Hearing loss is a complicated science and can be caused by numerous different sources, said Sandie Bass-Ringdahl, coordinator of the Communication Disorders and Sciences program in the university’s rehabilitation institute in Rehn Hall.

“You can be born with it, it could be something that is due to a medication you take (or) you can have a virus that causes hearing impairment,” she said. “There are just many things and, of course, there is noise exposure.”

Bass-Ringdahl said the ear’s hair cells that pick up vibrations can be damaged or destroyed from noise or consistent noise at a certain level. She said the dead hair cells remain inoperative, but it is possible scientists will find a way to regenerate them in our lifetime.

Only a hearing aid or a cochlear implant, which is a surgically implanted device that provides a sense of sound for individuals who are severely deaf or hard of hearing, can help individuals with hearing loss at this time, Bass-Ringdahl said.

The potential for D-methionine is astounding and is thrilling for the field, she said.

“It’s really exciting that Dr. Campbell has a potential medication that might be able to prevent noise-induced hearing impairment,” she said. “That’d be really exciting.”