The Future of Hearing Therapeutics and Protective Therapies and the Potentially Profound Impact on Patients and Providers

Over the past two decades, I have worked with thousands of patients across the lifespan, using diagnostic audiology practices, as well as fitting hearing aids and auditory implants. Among medical interventions, cochlear implants are routinely labeled the most successful neural prosthesis. This life-changing technology has afforded children with severe-to-profound sensorineural hearing loss the auditory access necessary for successful development of listening and spoken language, as well as the potential for age-normative speech, language, academic proficiency, quality of life (for child and family), and auditory-driven socialization. For adults, cochlear implants significantly improve quality of life and allow recipients to maintain active social lives and professional activities highly dependent on auditory-based interpersonal communication.

Despite the tremendous success of this Lasker-Award-winning technology—and nearly 750,000 recipients worldwide—cochlear implantation currently does not restore typical auditory fidelity, even for the highest-performing individuals. Cochlear implant outcomes are also highly variable, spanning the range of 0 to 100 percent on various measures of speech and auditory perception. Furthermore, too many children display persistent speech, language, academic, and social difficulties despite early implantation and early speech/language intervention.

Most patients, and especially parents of infants and small children with hearing loss, inquire about the availability and success of various molecular, pharmacological, and stem-cell therapies aimed at hair-cell regeneration or gene therapy. The reality is that there is a critical time window during which a child must acquire sufficient auditory access to achieve the typical development of speech, language, and auditory skills.

Thus, children diagnosed today with severe-to-profound sensorineural hearing loss will absolutely achieve their best possible outcomes via cochlear implantation, rather than waiting for therapeutics that have not yet entered clinical trials in children. However, we are at a point in scientific discovery that various therapeutics approaches, including gene therapy, are rapidly becoming a reality. This is an exciting time to be an audiologist, as our unified professional goal is to help individuals overcome communication barriers resulting from hearing loss.

I believe that we are on the precipice of a paradigm shift in our approach to rehabilitative audiology. For those of us working with rehabilitative technologies such as hearing aids and cochlear implants, we must not be concerned about our professional relevance and value as we enter this new phase, which will include auditory regenerative medicine. Our professional value is in our widespread knowledge of the auditory system and the effects of hearing loss on nearly all aspects of communication.

Our value and professional practice will be critical, as we will provide diagnostic and auditory assessments regarding the effectiveness of various therapeutic agents. Additionally, it is not even necessarily the case that hearing therapeutics will render hearing aids and auditory implants obsolete. Rather, I foresee a synergistic effect of regenerative therapies and hearing technology that will allow hearing aid users and cochlear implant recipients to achieve even better outcomes than today.

We may expect to see hearing aid users whose underlying pathophysiology will be prevented from progressing to the point of cochlear implant candidacy. We may also expect to see greater instances of acoustic-hearing preservation with cochlear implantation resulting in significantly improved auditory, speech, and music perception. We may even significantly reduce the variability in outcomes following the fitting of hearing technologies (i.e., MicroRNA profiling in the perilymph of cochlear implant recipients).

Finally, I foresee that many of our current cochlear implant recipients may still be able to benefit from future restorative therapies, given the prevalence of minimally traumatic surgical techniques associated with cochlear implant surgery and the use of flexible, atraumatic electrode arrays, which allow for the preservation of residual acoustic hearing and underlying cochlear and neural substrate.

This special issue of the Journal of the American Academy of Audiology includes original studies and detailed reviews from a group of scientists and clinician/scientists on the cutting edge of hearing restorative and protective therapies. Most of the refereed studies in this space are published in journals focused on the basic sciences such as cell and developmental biology, genetics, and molecular therapies. Unfortunately, unless we are actively seeking this information, we will not be well informed, as these reports are not aimed at audiologists—a group of professionals who will be on the front lines of validating therapeutic effectiveness and ultimately determining the clinical utility and efficacy of regenerative medicine in the otology and audiology clinics of the world.

This special issue contains some of the latest information about a number of hearing therapeutic and protective interventions, some of which are active in human clinical trials (i.e., FX-322) and some that are approaching Phase 1 trials aimed at determining safety and efficacy in human subjects (i.e., genetic therapies targeting otoferlin mutation). I look forward to working with my audiology colleagues as we enter a new phase of clinical and scientific practice.

René Gifford, PhD, is the director of the Cochlear Implant Program and the Cochlear Implant Research Laboratory at Vanderbilt University Medical Center and a professor in the Department of Hearing and Speech Sciences at Vanderbilt University. She is a consultant for Advanced Bionics (AB), Cochlear, and Akouos, as well as a clinical advisory board member for Frequency Therapeutics.

Publication History

Article published online:
24 May 2022