More than 1.5 billion people - nearly 20% of the world’s population - live with hearing loss globally, with 430 million suffering from disabling hearing loss. In this article, we take a look at five of the top hearing loss companies making efforts to reduce these figures. \n\n\n\nAccording to the World Health Organization (WHO), nearly 2.5 billion people are expected to have some degree of hearing loss, and at least 700 million of those people will require hearing rehabilitation. However, it is thought that many of the causes leading to hearing loss could be avoided through public health strategies and clinical intervention.\n\n\n\nRecently, there have been some positive advancements made in hearing loss research within the biotech industry, including stem cell therapy, and there are currently several companies working on treatments for hearing disorders. Here, in no particular order, we take a closer look at five of those companies.\n\n\n\n\n\nSensorion\n\n\n\nHeadquarters: Montpellier, FranceFounded: 2009\n\n\n\nUsing a three-pillar approach of restoration, treatment and prevention, Sensorion is working on developing a portfolio - which includes small molecule and gene therapy programs - of therapeutic solutions to address an unmet medical need in inner ear disorders. The company has built an R&D technology platform to expand its understanding of pathophysiology and etiology of diseases related to hearing loss, allowing it to select the best targets and mechanisms of action for drug candidates. \n\n\n\nSENS-401 is Sensorion’s clinical-stage small molecule drug candidate, which aims to treat and protect against inner ear lesions that lead to nerve degeneration and sensory hair cell loss. It is currently in a phase 2a clinical trial for the prevention of residual hearing loss in patients scheduled for cochlear implantation, and in a phase 2 clinical trial for the prevention of cisplatin-induced hearing loss. In January, it was announced that the first patient was enrolled in its phase 2a proof of concept clinical trial of SENS-401 in cisplatin-induced ototoxicity. \n\n\n\nSENS-401 has been granted orphan drug designation by the European Medicines Agency (EMA) in Europe for the treatment of sudden sensorineural hearing loss, and by the U.S. Food and Drug Administration (FDA) in the U.S. for preventing platinum-induced ototoxicity in pediatric patients.\n\n\n\nAs part of its broad strategic collaboration with Institut Pasteur, the company also has two ongoing gene therapy programs aimed at correcting hereditary monogenic forms of deafness. OTOF-GT targets deafness caused by mutations of the gene encoding for otoferlin, while GJB2-GT targets hearing loss related to mutations in the GJB2 gene. OTOF-GT was granted a rare pediatric disease designation and an orphan drug designation by the FDA in 2022. More recently, it was announced that Sensorion entered a collaboration with EVEON to design and develop an injection system for the delivery of Sensorion’s gene therapy products.\n\n\n\nFennec Pharmaceuticals\n\n\n\nHeadquarters: Durham, U.S.Founded: 1996\n\n\n\nFennec Pharmaceuticals has been around since 1996, and is committed to combating cisplatin-induced hearing loss in pediatric cancer patients, with the ultimate aim of preventing children enduring further hardship while they undergo chemotherapy. \n\n\n\nCisplatin - a platinum-based chemotherapy drug used to treat cancer - can cause ototoxicity by damaging the sensory hair cells which trigger the nervous system to communicate with the auditory cortex of the brain, resulting in hearing loss. Once these hair cells have been destroyed, they cannot grow back, meaning the effects are often irreversible. Young children are generally more vulnerable to the ototoxic effects of cisplatin-based chemotherapy due to the fact their ears are still developing. \n\n\n\nIn August 2022, Fennec Pharmaceuticals completed the first closing of $5 million of senior secured promissory notes under its investment agreement with Petrichor Healthcare Capital Management. Shortly after, in September 2022, Fennec Pharmaceuticals announced a second closing of $20 million from Petrichor, after the FDA approval of its prescription drug, PEDMARK.\n\n\n\nSupported by more than 10 years of study, the company's drug PEDMARK is the first and only FDA-approved sodium thiosulfate (STS) formulation for cisplatin-induced ototoxicity, and helps reduce the risk of cisplatin-induced hearing loss in patients aged one month and older with localized, non-metastatic solid tumors.\n\n\n\nSound Pharmaceuticals \n\n\n\nHeadquarters: Seattle, U.S.Founded: 2001\n\n\n\nSound Pharmaceuticals is a privately-held biopharma company pioneering neurotological drug development to treat sensorineural diseases of the inner ear. Its pipeline includes therapeutic candidates for Meniere’s disease (MD), acute noise-induced hearing loss (NIHL), aminoglycoside-induced ototoxicity and COVID-19.\n\n\n\nThe hearing loss company’s lead candidate, SPI-1005, is a proprietary oral formulation of ebselen and is a small molecule mimic and inducer of glutathione peroxidase (GPx), which is the dominant catalytic antioxidant enzyme in the cochlea that plays a critical role in auditory function. The drug works by mimicking the catalytic activity of GPx1 by using a bound selenonitryl moiety at its active site and cycling with glutathione (GSH) or other thiols.\n\n\n\nIn 2022, Sound Pharmaceuticals enrolled the first patient in its phase 3 clinical trial involving SPI-1005 for the treatment of MD, which marked the first phase 3 trial of an investigational new drug for the disease. Clinical data from phase 1b and phase 2b trials showed that SPI-1005 - when delivered orally for 21 or 28 days - improved sensorineural hearing loss and tinnitus in patients affected by MD.\n\n\n\nAlso in 2022, the company announced it had received a $4.2 million grant award from the National Center for Advancing Translational Sciences (NCATS) at the National Institutes of Health (NIH) to test SPI-1005 in two phase 2 clinical trials for the treatment of hospitalized patients with COVID-19, as the drug was shown to inhibit SARS-CoV-2 in three separate in vitro studies.\n\n\n\nDecibel Therapeutics\n\n\n\nHeadquarters: Boston, U.S.Founded: 2015\n\n\n\nDecibel Therapeutics was launched in 2015 by Third Rock Ventures with a $52 million series A financing to discover new medicines to protect, repair and restore hearing. To achieve its goal, the company is working on developing regenerative and gene therapy strategies.\n\n\n\nIt has built a proprietary platform that integrates single-cell genomics and bioinformatics analyses, precision gene therapy technology and expertise in inner ear biology to advance its pipeline of preclinical gene therapy programs. The programs are designed to selectively replace genes for the treatment of congenital, monogenic hearing loss, as well as restore inner ear hair cells to treat acquired hearing and balance disorders.\n\n\n\nDecibel Therapeutics’ lead candidate - developed in partnership with Regeneron Pharmaceuticals - is known as DB-OTO, and is an adeno-associated viral (AAV) dual vector gene therapy designed to restore hearing in individuals born with profound hearing loss as a result of the mutation of the otoferlin (OTOF) gene - a protein expressed in cochlear inner hair cells that enables the communication between the sensory inner ear cells and the auditory nerve through the regulation of synaptic transmission. Mutations in the OTOF gene disrupt the signaling between the ear and the brain, leading to hearing loss.\n\n\n\nIn 2022, the hearing loss company received FDA clearance of its investigational new drug (IND) application for DB-OTO, with phase 1/2 clinical trials of DB-OTO in pediatric patients expected to begin this year.\n\n\n\nAkouos\n\n\n\nHeadquarters: Boston, U.S.Founded: 2016\n\n\n\nAkouos also focuses on inner ear disorders, with an aim to advance precision genetic therapies to restore, improve and preserve hearing. It is developing targeted AAV (adeno-associated viral) vector-based gene therapies for sensorineural hearing loss, which is the most common form of hearing loss, by advancing multiple candidate therapies that target both sensory and nonsensory cells. \n\n\n\nThe company’s lead program, AK-OTOF, is an AAV gene therapy for the treatment and potential restoration of hearing in people suffering from sensorineural hearing loss due to mutations in the OTOF gene. In 2022, the company received clearance from the FDA of its IND application for AK-OTOF, and has plans to initiate a pediatric phase 1/2 clinical trial to evaluate the therapy for the treatment of OTOF-mediated hearing loss.\n\n\n\nAkouos was acquired by Eli Lilly and Company in December 2022, in an expansion of Lilly’s efforts in genetic medicines to include Akouos’ portfolio of potential first-in-class AAV gene therapies for the treatment of inner ear disorders.