The multichannel auditory brainstem implant (ABI) has now been used with some benefit in more than 1000 deaf patients worldwide who were not candidates for a cochlear implant (CI). For many years, the ABI was used primarily in adults deafened by Neurofibromatosis-Type 2 (NF2). During the past decade, ABI surgery has been safely performed on non-NF2 children outside of the United States, and results have shown great promise. The overall objective of this Phase I Clinical Trial grant is to evaluate safety in ten pediatric subjects who are not candidates for traditional cochlear implants due to cochlear nerve deficiency, cochlear aplasia, or cochlear ossification. These types of pathologies prevent normal transmission of auditory information between the cochlea and the brainstem. The House Research Institute proposes the first pediatric, non-NF2 ABI clinical trial in the United States. The Primary Aim is to describe the safety aspects of device implant surgery and 12- month use of an ABI in 10 pediatric patients with profound bilateral hearing loss not amenable to other treatments. If the surgical safety analysis shows no greater number of serious surgery-related adverse events than is commonly observed in non-NF2 adults undergoing craniotomy with or without an ABI and no more than four unexpected serious device-related adverse events are observed per these 10 subjects during 12 months of follow-up;then a Phase II study with a larger number of subjects will be proposed. A Secondary Aim will determine whether or not the device provides patients with access to sound (thresholds of 50 dB HL) during a critical period for communication skills development. Efficacy is here defined as access to sound at a level and within the frequency range, known to be associated with speech. Successful outcomes from this Phase I Clinical Trial will provide the necessary information for planning a Phase II investigation.
Early access to sound in children who are born deaf is crucial from a physiological standpoint because there is a critical period for maturation of the central auditory system. In the past, children born with profound bilateral hearing loss with etiologies no amenable to cochlear implantation have been denied adequate access to sound. The auditory brainstem implant (ABI) may provide an avenue of treatment for children whose etiology portends poor development of auditory skills with a cochlear implant. This Phase I feasibility safety study is the first pediatric ABI (non NF2) clinical trial to be conducted in the United Stats with FDA regulatory oversight.