The proposed ANI funded by the parent grant (1UG3NS107688-01) is a new central auditory prosthesis that targets the auditory nerve to substantially improve hearing performance (tonal range and resolution) over the current standard cochlear implant by interfacing directly with the auditory nerve. The funded parent grant supports the development and all necessary biocompatibility, safety and functional pre- clinical testing required to obtain an FDA Investigative Device Exemption (IDE) for the first in human demonstration in the UH3 part of the project. Since the start of the project in October 2018 it has become clear through discussions with the surgical team as part of the ongoing cadaver studies and a new FDA guidance on MRI compatibility for implantable devices, that a) having the ability to carry out an MRI in a human subject without the need to surgically remove the electrode would after all be highly desirable if not necessary, given the selected patient group(s) and b) that third party safety testing according to the new guidance is required to satisfy the need for highest possible safety for the study participants. These additional tasks were not anticipated or budgeted for in the original proposal. While the majority of regulatory, GMP and fabrication costs can be absorbed or are not affected by this additional task, the cost for the specific test devices and the third-party MRI testing provider would need to be added to the current budget through an administrative supplement. The third- party cost would be an overhead exempt pass through cost. The supplement project will evaluate potential safety hazards in patients with ANI devices for 1.5 and 3 T MRI systems through simulation and testing. This data will be provided to the FDA as part of the future IDE application and to BfArM for approval for use in the ANI clinical trial in Hannover, Germany. Based on a preliminary assessment, we anticipate that the generated data would support that the device can be considered conditionally MRI safe. If the full system is considered not MRI safe, then we can cut the cable and remove the stimulator module which only requires a superficial surgery and not the more invasive intracranial surgery to remove the electrode and assembly, assuming that the latter is passing the MRI safety testing. It will however stop the ability of patients to continue to participate in the study and to generate data. Only if the system and the electrode assembly are both considered MRI unsafe, would a full removal surgery be required. Beyond the specific need for this project, the supplement project will generate important safety, reliability and functionality data that can properly inform the design of a future clinical ANI devices and products at an early stage in the development cycle. The ability to allow MRI imaging in patients with chronic neuromodulation implants is seen as a critical potential barrier to widespread use.
This is an administrative supplement to the funded NIH grant, 1-UG3NS107688-01. Here we conduct tests to verify and understand safety aspects of the developed auditory nerve implant (ANI) device during magnetic resonance imaging (MRI).
