Envoy Esteem Totally Implantable Hearing System: phase 2 trial, 1-year hearing results.

Objectives: (1) To assess outcomes of the Envoy Esteem Totally Implantable Hearing System as measured by hearing results compared with preimplant baseline unaided (BLU) and best-fit aided conditions (BLA) and (2) to determine safety of the device.

Study Design: Prospective, nonrandomized, multicenter, subject-as-own-control, US Food and Drug Administration (FDA) trial.

Setting: Private practice and hospital-based.

Subjects And Methods: Between January 2008 and August 2009, an FDA trial was performed at 3 sites. Fifty-seven subjects with bilateral, mild to severe sensorineural hearing loss, with discrimination greater than 40%, were implanted. Implanted components were (1) a sound processor and (2) 2 piezoelectric transducers (a sensor and a driver). A sound processor was implanted in the temporal bone. Transducers were coupled to the ossicles. Devices were activated 2 months postimplant. Hearing results were compared with ipsilateral BLU and BLA.

Results: Speech reception thresholds (SRTs) improved from BLA of 41.2 dB to 29.4 dB with the Esteem (P ≤ .001). Word recognition score (WRS) at 50 dB hearing level (HL) improved from BLA of 46.3% to 68.9% with the Esteem. Pure tone averages improved by 27 ± 1 dB (confidence interval, 30-25). There were no changes in bone conduction. QuickSIN results showed no change. There were 6 serious adverse device effects: 2 wound infections (1 resolved medically, 1 required explantation), 1 delayed facial paralysis that resolved with medication, and 3 revisions due to limited benefit.

Conclusion: Phase 2 results at 12 months post implant demonstrated that (1) hearing results with the device are statistically superior to baseline best-fit hearing aids for SRT and WRS and (2) the device is safe.