Hearing Loss Facts

Epidemiology of Hearing

Hearing loss is a serious problem worldwide

  • 48 million people in the U.S. have some degree hearing loss

  • 278 million (2%) worldwide have disabling hearing loss

  • 10-20% patients treated with aminoglycoside antibiotics develop hearing loss

  • 60-80% treated with anti-cancer drug cisplatin develop hearing loss

  • 60% recent U.S. war veterans suffer hearing loss

  • 3:1000 children are born deaf or hard-of-hearing

  • 50:1000 ICU babies have serious hearing loss

There is currently NO available drug that protects against any form of hearing loss

 

Hearing Loss and Balance Disorders Result from Damage to Hair Cells

  • Hair cells are the sensory receptors of the inner ear used to detect sound and perceive bodily motion for balance.

  • There is a direct relationship between hair cell loss and hearing loss and/or balance problems

  • Humans start with only ~15,000 hair cells in each cochlea.

  • When hair cells are lost due to mutation, disease, injury, or exposure to environmental toxins, they are not replaced.

Hair cells do not regenerate in mammals

Aminoglycosides Use

Aminoglycoside antibiotics (AGs) are some of the earliest and most effective antibiotics. They continue to be used worldwide to treat a variety of life threatening bacterial infections including: pulmonary infections in patients with cystic fibrosis, non-tuberculous mycobacterial (NTM) lung disease, complicated urinary tract infections, endocarditis, neonatal septicemia, pseudomonas respiratory infections, and multiple drug resistant tuberculosis. With that efficacy, however, comes the risk of permanent hearing loss and balance problems, which can have a significant impact on quality of life. All aminoglycoside antibiotics carry boxed warnings regarding the potential for loss of hearing and balance, and multiple studies have reported the incidence of measurable hearing loss in patients undergoing short courses of AG therapy (< 3 weeks) at up to 20%.  Hearing loss is even more common in long duration therapy.  It is reported that as many as 35% of NTM patients, treated for up to three months with amikacin, have inner-ear issues, some requiring cessation of therapy.  Among those patients who require repeat courses of aminoglycosides over their life, such as people with cystic fibrosis, it has been reported that that between ~25%  and ~80% of individuals experience hearing loss.

Despite this limitation, based on data provided by IMS Health, there are still more than 500 million patient-days of parenteral AGs given worldwide each year.

Market

Annual Doses Parenteral Aminoglycosides

United States

8,000,000

Rest of Developed World

50,000,000

Rest of World

500,000,000

Total Annual Doses

558,000,000

The availability of an adjunct therapy to protect against the ototoxic side effect of AGs would allow AGs to be used worldwide in more cases as a first-line therapy and to treat additional infections where currently they are avoided.