Decibel Therapeutics is translating recent scientific advances in understanding the factors that cause hearing loss into novel therapies for a broad range of people with hearing disorders. By combining recent innovations in hearing science with leading diagnostic tools, biological insights, modeling and therapeutic delivery techniques, Decibel is pioneering a comprehensive approach to defining the underlying biological causes of hearing loss and developing a pipeline of breakthrough therapies targeted to specific patient populations.

Hearing loss is commonly mischaracterized as an issue only associated with aging, but continues to be a serious and growing concern for people of all ages. Explained below are significant hearing disorders, and symptoms of hearing loss such as tinnitus, that affect millions of people, but may be less familiar to the general public. Decibel Therapeutics’ goal is to be the leading company focused broadly across hearing disorders, including: children with cancer or cystic fibrosis who commonly experience ototoxicity, or hearing loss as a side effect of drug treatment; noise-induced hearing loss; residual hearing preservation or improved sound fidelity with cochlear implants; presbycusis, or age-related hearing loss; tinnitus, a symptom of underlying hearing conditions that manifests as a persistent ringing in the ears; and genetic hearing loss.

The underlying science of hearing has reached a tipping point, and we’re closer than ever to understanding the molecular basis of the pathogenesis and pathophysiology of hearing loss. Decibel has identified acute, targeted indications that that can provide near-term opportunities for human proof-of-concept for the company’s therapeutic candidates. These clinical studies will evaluate therapies for people with significant unmet needs, as well as provide the foundation for moving into larger, chronic hearing disorders. Decibel’s goal is to be the world leading hearing therapeutics company.

Ototoxicity

Drug-induced ototoxicity is hearing loss resulting as a side effect from exposure to certain therapeutics used in the treatment of, for example, children with cancer or cystic fibrosis. There are more than 600 ototoxic drugs and chemicals that have been identified as causing hearing loss or tinnitus; however, the overall incidence of drug-induced ototoxicity is unknown.5 Some studies have suggested that as many as 3 cases per 1,000 people taking prescription medication result in drug-induced hearing loss.5 Platinum-based anti-cancer drugs (such as cisplatin and carboplatin), aminoglycosides and loop diuretics are among the most commonly prescribed ototoxic drugs.5 Cisplatin and carboplatin are important drugs in the treatment of childhood cancer; however, children are often at greater risk of permanent hearing loss as a side effect of treatment, which can lead to developmental delays (e.g., learning difficulty, speech impairment) and significantly affect quality of life (e.g., social interaction, cognitive development). The “ear age” of these adolescents is often akin to the middle aged or even elderly, and their hearing disorders tend to worsen over time. Eventually, many must rely on cochlear implantation as a means of restoring hearing thresholds; however, given the limitations of these device interventions, they often continue to suffer from poor speech recognition and sound fidelity issues.

Tinnitus

Tinnitus is the perception of sound when no external noise is present. It is commonly referred to as “ringing in the ears,” but can manifest as many different types of sounds, including buzzing, hissing and swooshing. In most cases, tinnitus is a sensorineural reaction to damage in the ear and auditory system. The U.S. Centers for Disease Control estimates that nearly 15% of the general public — over 45 million Americans — experience some form of tinnitus. Roughly 20 million people struggle with burdensome chronic tinnitus, while 2 million have extreme and debilitating forms.4 Along with hearing loss, tinnitus is one of the two most prevalent military service-connected disabilities.3

Noise-Induced Hearing Loss

Approximately 15% of people in the U.S. (26 million people) between the ages of 20 and 69 have “high frequency” hearing loss due to exposure to noise at work or during leisure activities.1,2 This type of hearing loss is particularly common among military personnel who experience close-range exposure to blast-related and gunfire sounds, and ranks as one of the most prevalent military service-connected disabilities.

Genetic Hearing Loss

A genetic defect is the most common cause of hearing loss at birth and in childhood. Recent advances have shed light on the multiple genes associated with hearing disorders; mutations in more than 100 genetic loci have been linked to genetic deafness.6 However, although numerous causative genes for genetic hearing loss have been identified, there are no curative treatments for these conditions.

Presbycusis

Hearing loss that is associated with aging, known as presbycusis, is very common, affecting nearly two-thirds of individuals over 70 years of age.7 The decline of hearing ability with age manifests itself in different ways, including the difficulty detecting weak sounds or deciphering speech in a noisy environment. While some people in this population are eligible for hearing aids, only 1 out of 5 people who could benefit from a hearing aid actually wears one.4 As a result of this declining hearing, the elderly with hearing disorders can feel more isolated from their surroundings and loved ones and colleagues and go on to develop depression.