Hearing Impairment, Sensorineural

The RH210A is an air-conduction hearing aid designed for adults with perceived mild-to-moderate sensorineural hearing loss. The purpose of this clinical investigation is to generate objective and subjective evidence of the clinical performance and safety of the device.

The goal of this clinical trial is to determine the efficacy of Clemastine Fumarate in the presence of engineered sound to treat age-related central auditory processing disorder (CAPD). This disorder impacts 800M patients worldwide, including \~1/3 people over 40 years of age and \~1/2 people over 65, resulting in an inability to hear in noisy environments. The primary hypothesis this study aims to test is: engineered sound, driving localized neural circuit activity, will enable Clemastine Fumarate to mature Oligodendrocyte cells and thus remyelinate these activated neural circuits. This Localized Oligodendrocyte Optimization Therapy (LOOT) was highly effective in preclinical animal studies so this clinical trial aims to answer if this therapy will translate to humans. The study is an adaptive design intended to compare the efficacy of the drug in the presence or absence of the engineered sound for improving hearing in noise ability. Trial participants will be tested for hearing thresholds and ability to isolate a sound signal from background noise. If they meet the inclusion criteria, they will be enrolled into one of the four arms of the study and undergo the proposed one-month treatment (drug and sound or respective placebos). After the treatment period, trial participants will be tested again for hearing thresholds and their ability to isolate s sound source of interest from background noise. The hypothesis to be tested in this clinical trial is that the one-month treatment will significantly improve the participant's ability to isolate a sound source of interest from background noise. The design has four arms, drug+sound, placebo+sound, drug+white noise, and placebo+white noise. Based on our preclinical data, control arms are all expected to show identical results, thus our adaptive design includes interim analyses to allow for dropping of two of the three placebo arms should the preclinical results be replicated as anticipated. We will also monitor each participant's general health during the duration of the clinical trial, which will be done by performing a number of blood tests, an EKG and a general physical before and after the one-month treatment period. We expect no significant changes since participants will take the drug for the one-month period at dosages already demonstrated safe in several Phase II studies of multiple sclerosis. Similarly, the engineered sound will be listened to for one hour per day during this month at sound intensities well below threshold that might cause noise-induced hearing damage.

The overarching hypothesis to be evaluated using this protocol is that age-related hearing loss (ARHL) leads to shifts in the functional spatial boundaries between segregated and integrated auditory streams, and that hearing aid intervention that relies on directional processing schemes is most effective for those that have the poorest spatial sensitivity. One key component of the research design is to measure both behavioral and neurophysiological indices of an individual's spatial segregation boundary. The second key component is to measure the cost or benefit associated with hearing aid intervention in older hearing-impaired listeners. The final component is to relate cost and benefit of hearing aid intervention to spatial sensitivity measures that might predict the efficacy of clinical intervention.