About 15 percent of American adults report some trouble hearing, and the National Institute on Deafness and Other Communication Disorders (NIDCD) estimates that fewer than one in three of those aged 70 and older with hearing loss who could benefit from hearing aids has ever used them. ( http://1.usa.gov/1t04a9L.)
Biotechnology companies are paying attention to these unmet needs, and are in different stages for investing in and researching hearing treatments. Recently, a new company called Decibel Therapeutics raised $52 million in Series A funding for its launch, with investment from Third Rock Ventures, a biotechnology-focused venture capital firm, and SR One—the venture capital arm of pharmaceutical giant GlaxoSmithKline.
“Our goal is to catalyze some very significant change in the entire space of hearing disorders. There's really very few options for patients, and so our goal is to systematically go through the clinical presentation, through a better diagnosis of circuit deficit, and hopefully correct that circuit deficit. We simply say we want to protect, we want to repair, and we want to restore,” said Kevin Starr, Decibel Therapeutics’ CEO.
The company's initial targets, Mr. Starr explained, are spanned across three areas. Two or three patient groups in ototoxicity would lend itself to therapeutics, the first being platinum-treated kids with cancer.
“There's now lots of evidence that says platinum-based therapy sticks around in hair cells and other cells in the inner ear for decades, so we'd like to protect those ears against the ravages of platinum therapy,” Mr. Starr said.
Another is aminoglycoside, whether it's tuberculosis or cystic fibrosis, or others. Patients who have a constant need for aminoglycoside therapy suffer the same fate as those with platinum therapy for cancer. The second set of programs are directed at restoration of noise-induced hearing loss.
“We believe through our current treatment—post injury—we could restore that synaptopathy. The third category is working for patients that are candidates for cochlear implants. We're working at neurite extension from the spiral ganglion neurons to ultimately change fidelity in use of cochlear for long-term,” Mr. Starr said.
Oral and injected treatments will work with hearing devices, not in lieu of them.
“I don't think there's going to be anything that's a panacea because there's many different causes of hearing loss. There are genetic causes of hearing loss. … It can be caused by an explosion, or it can be caused by a structural abnormality. So, it's going to depend on the cause of the hearing loss whether or not any of these drugs are going to intervene,” said Kathleen Campbell, PhD, a professor at Southern Illinois University School of Medicine and a founder and chief scientific officer for MetArmor. Dr. Campbell is working with d-methionine in the hopes of creating a drug that targets noise-induced hearing loss. Almost four years ago, Dr. Campbell was testing the micronutrient in animal studies, which she said proved to be protective.
“I've been working with this compound for a long time, and I actually started working with it to prevent cisplatin-induced hearing loss. For the noise-induced hearing loss, we're not unblinded yet, so we don't know whether it's effective in the current clinical trial. The design is strong, but you never know until you actually unblind your data and take a look. But we are in Phase Three for noise-induced hearing loss. And then in our pre-clinical work, we can also reverse the noise-induced hearing loss. So, even if we start it at 24 hours after that noise ceases, we can reverse it back,” Dr. Campbell said.
THE FUTURE OF MEDICINE
Despite an unknown launch date for new treatments to be on the market, Mark Parker, PhD, said he thinks it's important for audiologists and AuD students to make themselves aware of biotechnology's existence and future impact.
“I think it's important at this point because the graduating AuDs are going to be dealing with these types of technologies. People look to audiologists to be the leader in the room, so it would be nice to have some type of basis,” said Dr. Parker, the director of audiology in the Department of Otolaryngology-Head and Neck Surgery at Steward St. Elizabeth's Medical Center and an assistant professor of otolaryngology at Tufts University School of Medicine.
Device manufacturer companies like Phonak said it's still too early to infer the future of hearing aids and how they'll stand out in the future of biotechnology.
“It really depends on what we will get from a pharmaceutical treatment at the end of the day in terms of etiology, rehabilitation, application,” said a Phonak representative on behalf of the company.
Phonak also said they would be willing to discuss opportunities and potential synergies between pharmaceutical and rehabilitation through devices once any type of pharmaceutical solution becomes commercially available, though.
It seems, however, some companies are heating up. Sound Pharmaceuticals Inc., for example, is in Phase II trials to test an oral capsule targeted at cochlea cells. A little more than one year ago, the New York Times reported a clinical trial of a gene therapy being developed by Novartis that's aimed at restoring hearing loss ( http://nyti.ms/1KvDwhA ), and another clinical trial at the University of Kansas Medical Center uses a gene therapy that GenVec, a biotech company based in Maryland, developed, amongst others.
A MODERN TIMELINE
Though a future for biotechnology's role in hearing loss is still in the to-be-determined phase, James Hall III, PhD, said he's optimistic.
“Basic research on new treatment options for hearing loss is yielding promising findings. It's likely that start-up companies will soon seek FDA approval for innovative pharmaceutical agents for treatment of some forms of hearing loss,” said Dr. Hall, a co-founder of the American Academy of Audiology, a professor at the George S. Osborne College of Audiology at Salus University, and a member of The Hearing Journal’s Editorial Advisory Board. He said he predicts, however, that he and most of his colleagues won't live long enough to witness the implementation of new biotechnological therapy as a first-line widespread strategy for hearing loss intervention.
Mr. Starr has a sooner goal in mind, saying the company's objective is to be in the clinic in the next two to three years, but thinks they can beat even that.
“There are some programs that we think we can accelerate to the clinic even earlier than that, depending on how the FDA [U.S. Food and Drug Administration] gears those clinical trials we'd need for endpoints. The goal would be many new products after that coming out on a regular basis,” he said.
This surge of biotechnology, and Decibel Therapeutics’ contribution specifically, has a chance to make an impact on the future of the industry.
“If you look at your typical drug discovery and drug development, it's a process where we understand that pharmacological intervention does inside the body. The challenge—and one of the reasons for lack of therapeutic options in the hearing space—is that it's very hard to measure things in the ear and the cochlear. So what Decibel is doing is taking a very typical biotech approach in a drug-like manner. We can measure concentration of drug in the inner ear, we measure through transtympanic injection, kinetics of drugs passing through the round window. And those are going to be important long term as we bring more drugs to the market,” said Mr. Starr.
As a matter of fact, Dr. Parker said not only does biotechnology have a chance to make an impact, but it is the future.
“I'm not endorsing any of these products [specifically], but I think that this is the future of medicine. It's going this way,” he said.
Each company is developing drugs to work in different ways and for different purposes, which is fitting for treating a disability with several causes.
“New therapeutic targets to help people with hearing loss are an exciting development, which has applications in many areas where hearing loss is caused by ototoxic drugs. As one of the initial areas of focus for Decibel Therapeutics, positive results will greatly encourage continuing research. Many factors can cause hearing loss. The future of devices used in the rehabilitative process of restoring hearing will continue to provide benefit for millions who suffer,” said Deborah Price, AuD, the founder and owner of Hearing Professional Center in Dallas, and a member of The Hearing Journal’s Editorial Advisory Board.