One Potential Way to Cure Hearing Loss

At the end of May (May 30), a few days after Americans honored Veterans on Memorial Day, a New England biotech company announced that it had received a grant from the Department of Defense to research a therapeutic opportunity that may help reverse hearing loss.

Cochlear hair cells_Credit- W. McLean
Cochlear Hair Cells. Credit:W. McLean

A 2015 study of almost 50,000 soldiers showed that peak noise levels in combat can reach 180 dB. Combat veterans have a 63% increased risk for hearing loss. Two and a half million veterans have service-connected hearing disabilities.

Clearly there is a need for treatment.

Frequency Therapeutics based in Woburn, Mass., and Farmington, Ct., announced that it had received a $2 million grant from the Department of Defense to investigate the restoration of hearing after noise-related damage as a result of military service-related injuries.

Frequency’s Progenitor Cell Activation, or PCA Regeneration, technique, uses a combination of small-molecule drugs to stimulate inner ear progenitor cells to multiply and create new hair cells. Hair cell regeneration happens spontaneously in fish and birds, but not in mammals.

Humans are born with only 15,000 hair cells in each ear and do not develop any more after birth. Damage to these hair cells over time results in a loss of hearing. Figuring out how to make regeneration happen in mammals would be a major step towards finding a cure for hearing loss, and this goal is being pursued by others in addition to Frequency.

In December, Frequency announced the completion of the first in-human safety and tolerance study of its proprietary drug combination, FX-322. (You can read more about it here.) The drug is injected into the inner ear using a standard intratympanic injection, with the patient awake.  The Phase 1 trial was conducted at Victoria Eye and Ear Hospital in Melbourne, Australia, on 9 adults with severe to profound sensorineural hearing loss who were scheduled for cochlear implant surgery 24 hours after receiving the injection.

In the press release announcing the DOD grant, Frequency noted that the PCA Regeneration platform targets the root cause of disease without removing stem cells from the body. This avoids issues that can develop with traditional stem cell or gene therapy, which can affect cells other than those targeted. Frequency’s FX-322 awakens the dormant progenitor cells already in the ear, initiating cell division and differentiation to repair the damaged hair cells.

Frequency hopes this technique can be used elsewhere in the body as well, to restore healthy tissue, and it has a number of other programs in development including preclinical research in muscle regeneration and type 1 diabetes. Frequency plans to initiate a Phase 2 trial for hearing regeneration in the U.S. later this year.

This grant applies only to military personnel with service-related hearing loss, although of course if the technique is found to work it would be available to others with sensorineural hearing loss. More than 48 million Americans of all ages have some degree of hearing loss.

**

This study is one of many efforts to find a biological cure for hearing loss. I will be writing about others in the coming months. If you are a researcher with relevant information please email me at katherinebouton@gmail.com

 

The Noise of War

This Memorial Day, as we honor veterans with parades and flags and, yes, barbecues, we should remind ourselves of the toll that war takes on hearing.images

Two and a half million veterans have service-connected hearing disabilities. Tinnitus is the number-one claim for all service related disability, with more than 1.5 million veterans receiving disability benefits for it. Another million receive benefits for service-related hearing loss.

Master Sgt., Donald Doherty, a retired Marine and Vietnam veteran who is now the Chair of the Board of Trustees of the Hearing Loss Association of America, lost his hearing as a result of gunfire and artillery noise during his 1965-66 tour in Vietnam. He has worn hearing aids since June 1970. He recently retired from the Department of Veterans Affairs after 25 years of service.

Doherty is a member of “Heroes with Hearing Loss,” supported by HamiltonCapTel. Heroes with Hearing Loss is group of veterans who hold interactive workshops to help veterans and their families come to terms with hearing loss and find solutions. You can follow them on Twitter at @HWHLVeterans.

Hearing loss is even more an invisible disability in the military than it is elsewhere. Among veterans it is often overshadowed by other injuries. But as Heroes with Hearing Loss notes, hearing loss and other injuries are  “intertwined both physically and emotionally — as a trigger, a constant reminder or an everyday frustration. It is a very unique and personal challenge for many veterans.” The website has a useful list of resources and web addresses. 

For the past several years the group has held a packed workshop at HLAA’s annual convention, which will be held this year June 21-24 in Minneapolis. I wrote about their 2014 presentation in “An Invisible War Wound,” published on November 11th, 2014, Veterans’ Day.

“Marines — and anyone in the armed forces — have been instilled with a sense of pride, the need to act independently, to do it yourself. It’s a sign of weakness if you reach out for help,” Doherty said at that event. Eventually, you realize it’s affecting “not only yourself but everyone around you.” Heroes with Hearing Loss helps veterans accept help.

Captain Mark A. Brogan, Ret., was one of the speakers that year. He was injured in a suicide bomb attack while on active duty in Iraq in 2006, sustaining a severe penetrating head injury, multiple shrapnel wounds, and a nearly severed right arm. He spent months in a coma at Walter Reed Medical Center. It was not until his traumatic injuries had been treated, he said, that he began to be aware of his hearing loss and its permanency.  He also began to realize how hearing loss and TBI were entwined.  The part of the brain that controls speech perception was injured in the blast, he said, and that damage combined with physical injury to the ear to make speech difficult to understand. He knew he needed help, but like many in the military asking for help was difficult.

HLAA was founded in 1979 by Rocky Stone, who also suffered service-related hearing loss. HLAA continues to honor and offer resources for veterans, on both the national and chapter level. Mark Brogan joined the Knoxville, Tenn., chapter: “It’s just good to get with  others who have the same type of disability,” he says.

To see some of the ways HLAA is involved with veterans nationally, go to HLAA’s website, or just click through directly to “Veterans.”

For more information about living with hearing loss, see Katherine Bouton, Amazon.com.