CGF166 – Hearing Loss

CGF166 - a Regenerative Medical Approach to Hearing Loss and Vestibular Dysfunction

The Problem

Hearing loss and vestibular dysfunction (which causes imbalance disorders) are disabling conditions with high and increasing prevalence worldwide.  It is estimated that one out of every five people in the U.S. over the age of 12 has hearing loss.  There are currently no pharmacological treatments available.  

Approximately 90% of hearing loss is sensorineural, characterized by loss of sensory hair cells in the inner ear.  These sensory cells are critical to both hearing and balance and can become damaged or destroyed due to aging, infection, trauma from certain medications, or exposure to noise.

GenVec's Approach and Early Preclinical Testing

During embryonic development, an atonal gene (Atoh1) induces the differentiation of sensory cells in the inner ear.  We have demonstrated formation of new inner ear sensory hair cells and the restoration of hearing and balance function using our gene delivery technology to deliver Atoh1 to the inner ear in multiple animal models.


CGF166 was designed by GenVec and leverages our AdenoVerse™ technology platform.  In this case, utilizing our proprietary GV11 gene delivery system, featuring an E1-, E3-, E4-deleted human adenovector serotype 5 (Ad5) backbone.  CGF166 also features a cell-specific promoter that limits the expression of the atonal gene to the supporting cells of the inner ear.

Experiments in animal models testing CGF166 conducted by Novartis have confirmed that this experimental biological triggers the regeneration of sensory cells in both animal and human tissue models and the restoration of hearing in animal models.

CGF166 is now being tested in a Phase 1/2 clinical trial being conducted by Novartis.  The first patient was treated in October 2014, representing the first direct drug delivery to the inner ear.  

Partnership with Novartis

In January 2010, GenVec entered into a worldwide licensing and collaboration agreement with Novartis to discover and develop novel treatments for hearing loss and balance disorders.  CGF166 is the lead compound being developed under the terms of this agreement.  

Under the terms of the partnership with Novartis, GenVec received an upfront payment and is eligible to receive up to $213.6 million in payments based on the achievement of certain clinical, regulatory, and sales milestones.  GenVec is also entitled to royalties on future sales.  Novartis is responsible for all development and commercialization costs.  During 2014, GenVec received a $2 million milestone payment upon non-rejection by the FDA of the IND filed by Novartis for the Phase 1/2 testing of CGF166.  On November 5, 2014, GenVec announced a $3 million milestone payment had been achieved with the dosing of the first patient in the Phase 1/2 clinical trial.  Our next anticipated milestone will be the dosing of the first patient in a Phase 2B study of the experimental drug.