Hearing loss for many people is hereditary—a mutation in a single gene impairs hearing from birth. There are no approved drugs for this type of hearing loss, but biotech startup Akouos is developing a gene therapy to help patients recover the ability to hear.
Boston-based Akouos says it has secured a $50 million financial commitment to finance its research and development work, although a securities filing shows that it has the first $25 million in hand so far. “Our goal is to demonstrate efficacy in humans in the next four to five years,” says CEO Manny Simons.
Hearing involves tiny hair cells in the inner ear that convert vibrations into electrical signals. The auditory nerve carries these signals to the brain, where they are recognized as sound. In genetic hearing loss, the hair cells are present in the ear, but are not functioning properly because of the genetic mutation, Simons says. The Akouos approach employs an engineered adeno-associated virus (AAV) to deliver a functioning copy of the mutated gene into the cells of the inner ear.
Simons notes that his company’s AAV approach is the same one used by Spark Therapeutics (NASDAQ: ONCE), which last year won the first FDA approval for a gene therapy. Voretigene neparvovec (Luxturna) treats a rare, inherited form of blindness. Like the Spark gene therapy, Akouos’s therapy would be targeted to patients with a genetically defined form of the disease. The Akouos technology is based on the research of company founder Luk Vandenberghe (pictured above), who is also director of the Grousbeck Gene Therapy Center at Massachusetts Eye and Ear, and a professor of ophthalmology at Harvard Medical School. Simons says that Vandenberghe has data demonstrating that his viruses can reach parts of the ear that other viral vectors can’t.
Akouos is currently testing its treatment in animals but Simons says the company plans to talk with the FDA next year about human tests, with the goal of starting a clinical trial within the next three years. Simons says Akouos will use the financing to develop a pipeline of hearing loss gene therapies.
A number of other companies are trying to develop treatments for hearing loss, including gene therapies. MIT spinout Frequency Therapeutics is working on a way to activate “progenitor” cells, which lie dormant but have the ability to morph into other cells. Frequency, which raised $32 million in financing last year, is trying to get these cells to form new hair cells in the inner ear. Decibel Therapeutics closed a $55 million Series C round of financing in June to support its pipeline of experimental hearing loss treatments, including a gene therapy. The Boston-based company has not offered much detail about that gene therapy, though CEO Steven Holtzman told Xconomy at the time of the financing that this therapy could start human testing within two years. The Decibel compounds that are closer to clinical testing are meant to protect patients against other forms of hearing loss.
Those companies, and Akouos, are chasing Novartis (NYSE: NVS), which has advanced its gene therapy for hearing loss into early-stage clinical testing. The company says the growth of hair cells in the ear is governed by a gene that acts as a kind of “master switch.” This gene normally switches off after birth. The Novartis gene therapy, called CGF166, uses a virus to reintroduce the gene into the cochlea, the part of the inner ear that receives sound. This approach is meant flip the switch to the “on” position, stimulating the growth of the hair cells needed for proper hearing, Novartis says.
A securities filing shows that Akouos has raised $25 million in an initial tranche of funding. The remainder will kick in “upon the occurrence of certain events.” Simons declined to elaborate on the details of the financing. The round was led by 5AM Ventures and New Enterprise Associates, both of which also invested in the biotech’s $7.5 million seed round last November. Also participating in the latest financing are an earlier investor, Partners Innovation Fund, and new investors Sofinnova Ventures, RA Capital Management, and Novartis Venture Fund.
In addition to the financing, Akouos announced it has appointed Michael McKenna as chief medical officer. McKenna, a professor at Harvard Medical School since 2006, is a scientific co-founder of Akouos. The company also appointed Jennifer Wellman as its senior vice president, regulatory. Wellman was a co-founder of Spark Therapeutics and led that company’s regulatory work for its gene therapy.