Esteem Totally Implantable Hearing System New Subject Enrollment Post Approval Study
Phase: NA
Conditions: Sensorineural Hearing Loss
Sponsor: Envoy Medical Corporation

Envoy Medical Corporation, Inc. 
 
 
CONFIDENTIAL 
 
 
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Esteem Totally Implantable Hearing System 
 
Post Approval Study 
New Subject Enrollment  
 
Protocol Number 0205 
 
 
 
 June 14, 2010 
November 15, 2010 
January 05, 2016  
August 20, 2019 
 
 
 
 
CONFIDENTIAL                                                                                    DO NOT COPY 
 
 
THIS PROTOCOL CONTAINS CONFIDENTIAL INFORMATION FOR USE BY THE INVESTIGATORS 
AND THEIR DESIGNATED REPRESENTATIVES PARTICIPATING IN THE EVALUATION OF THE 
ESTEEM® SYSTEM.  IT SHOULD BE HELD CONFIDENTIAL AND MAINTAINED IN A SECURE 
LOCATION.  IT SHOULD NOT BE COPIED OR MADE AVAILABLE FOR REVIEW BY ANY 
UNAUTHORIZED PERSON OR FIRM. 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 

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TABLE OF CONTENTS 
1 
INTRODUCTION ....................................................................................................................................... 6 
1.1 
DEVICE NAME ..................................................................................................................................................... 6 
1.2 
DEVICE DESCRIPTION AND PRINCIPLE OF OPERATION ..................................................................................... 6 
1.2.1 
Anticipated Changes in Device .............................................................................................................. 6 
1.3 
INDICATIONS FOR USE ........................................................................................................................................ 7 
1.4 
JUSTIFICATION FOR THE INVESTIGATION ............................................................................................................ 7 
1.5 
DURATION OF THE INVESTIGATION ..................................................................................................................... 7 
2 
STUDY DESIGN AND OVERVIEW .......................................................................................................... 7 
2.1 
TRIAL DESIGN ..................................................................................................................................................... 7 
2.2 
INVESTIGATIONAL SITES AND NUMBER OF ENROLLMENTS ................................................................................ 7 
2.3 
TRIAL OBJECTIVES ............................................................................................................................................. 7 
3 
BENEFITS/RISKS ..................................................................................................................................... 8 
3.1 
POTENTIAL BENEFITS ......................................................................................................................................... 8 
3.2 
POTENTIAL RISKS ............................................................................................................................................... 9 
4 
TRIAL METHODOLOGY ........................................................................................................................ 11 
4.1 
SUBJECT SELECTION ........................................................................................................................................ 11 
4.1.1 
Inclusion Criteria ..................................................................................................................................... 11 
4.1.2 
Exclusion Criteria ................................................................................................................................... 11 
4.2 
SCREENING AND BASELINE .............................................................................................................................. 12 
4.3 
SURGICAL PROCEDURE .................................................................................................................................... 15 
4.3.1 
Preparation of the subject and Esteem® System placement .......................................................... 15 
4.3.2 
Driver and Sensor Placement .............................................................................................................. 15 
4.3.3 
Intra-operative Testing .......................................................................................................................... 16 
4.3.3.1 
Intra-operative Driver Testing ....................................................................................................... 16 
4.3.3.2 
Intra-operative Sensor Testing ..................................................................................................... 17 
4.3.3.3 
Intra-operative System Testing .................................................................................................... 17 
4.3.4 
Placement of Sound Processor ........................................................................................................... 17 
4.4 
POST-PROCEDURE/DISCHARGE ...................................................................................................................... 17 
4.5 
FOLLOW-UP ...................................................................................................................................................... 18 
4.5.1 
Post Implant Follow-up Visit(s) ............................................................................................................. 18 
4.5.2 
Activation Visit (8 weeks  2 week post implant) ............................................................................... 18 
4.5.3 
Follow-up Visits ...................................................................................................................................... 18 
4.6 
TESTING REQUIREMENTS ................................................................................................................................. 19 
4.6.1 
Device Revisions / Interventions .......................................................................................................... 20 
4.6.1.1 
Mastoid Approach (through the original incision) ...................................................................... 20 
4.6.1.2 
Ear Canal Revision ........................................................................................................................ 20 
4.6.2 
Removal of Subjects from Study ......................................................................................................... 20 
4.7 
ADVERSE EVENTS ............................................................................................................................................ 21 
4.7.1 
Definitions ................................................................................................................................................ 21 
4.7.2 
Reporting of Adverse Events ................................................................................................................ 22 
4.8 
DEVICE FAILURES AND MALFUNCTIONS ........................................................................................................... 22 
5 
STATISTICAL ANALYSIS ...................................................................................................................... 22 
5.1 
SAMPLE SIZE .................................................................................................................................................... 22 
5.2 
OBJECTIVE ANALYSIS ....................................................................................................................................... 22 
6 
ADMINISTRATIVE RESPONSIBILITIES ............................................................................................... 24 
6.1 
INSTITUTIONAL REVIEW BOARD (IRB) ............................................................................................................. 24 
6.2 
SUBJECT INFORMED CONSENT ........................................................................................................................ 25 
6.3 
CONFIDENTIALITY ............................................................................................................................................. 25 
6.4 
INVESTIGATOR TRAINING .................................................................................................................................. 25 
6.5 
INVESTIGATORS RESPONSIBILITIES.................................................................................................................. 26 
6.6 
DATA MONITORING AND QUALITY CONTROL ................................................................................................... 26 

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6.6.1 
Training .................................................................................................................................................... 26 
6.6.2 
Case Report Forms (CRFs) .................................................................................................................. 26 
6.6.3 
Data Reporting ....................................................................................................................................... 26 
6.6.4 
Data Review ............................................................................................................................................ 26 
6.7 
RECORD MAINTENANCE ................................................................................................................................... 27 
6.7.1 
Records ................................................................................................................................................... 27 
7 
REPORTS (INCLUDES ANNUAL REPORTS, FINAL REPORTS FROM INVESTIGATOR AND 
SPONSOR) ............................................................................................................................................. 27 
7.1.1 
Reports .................................................................................................................................................... 27 
7.1.2 
Investigator’s Final Report .................................................................................................................... 28 
7.2 
INVESTIGATIONAL SITE MONITORING PROCEDURE ......................................................................................... 28 
7.3 
LABELING:  INSTRUCTIONS FOR USE ................................................................................................................ 28 
7.4 
DEVIATIONS FROM PROTOCOL ......................................................................................................................... 28 
7.5 
INVESTIGATIONAL SITE TERMINATION .............................................................................................................. 28 
ATTACHMENT A: 
SAFETY ALGORITHM .................................................................................................. 29 
 
PROTOCOL SUMMARY 
 
Title: 
Esteem Totally Implantable Hearing System Post-Approval Study 
Purpose: 
To evaluate the safety and efficacy of the Esteem® Totally Implantable 
Hearing System (hereafter called the Esteem® System) implanted by 
newly-trained surgeons in subjects suffering from moderate to severe 
hearing loss. 
Trial Design: 
The Post-Approval Study is similar to the PMA pivotal clinical trial, which 
was designed as a prospective, multi-center, non-randomized, clinical 
trial to evaluate the safety and efficacy of the Esteem® System.  For this 
trial the subject acts as his or her own control.   
This trial has been designed to meet the United States’ regulatory requirements.   
 
Enrollment Size: 
A minimum total of 45 new subjects will be enrolled and implanted in this 
study, with the requirement of 45 evaluable subjects for analysis of 
efficacy endpoints. For safety endpoints, a minimum of 109 evaluable 
subjects will be required. 
                                                
 
Subject Population: 
Subjects 18 years of age and older who have moderate to severe 
sensorineural hearing loss (HL) defined by PTA, have a healthy middle 
ear, have an unaided speech discrimination score of equal to or better 
than 40%, and have previously worn a hearing aid for a minimum of 30 
days are eligible for inclusion in the Post Approval Study.  See detailed 
inclusion/exclusion criteria for specifics.   
 
Questions:                                The following questions are to be answered: 
 
Is the Esteem® effective through 1 year follow-up? 
 
Is the Esteem® safe through 1 year follow-up? 
 
Is the incidence of facial pareses/paralysis at 1 month follow-up 
no greater than 7%? 
   
 
Primary Objectives: 
 
 

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1. To demonstrate that the Esteem® System improves the speech 
threshold of sensitivity for hearing and identifying speech signals as 
well as or better than the pre-implant hearing aid (aided condition). 
Endpoint: Comparison of the speech reception threshold 
(SRT) using the Esteem® System as compared to the pre-
implant aided condition. 
 
2. To demonstrate that the Esteem® System is as effective as or 
better than the hearing aid for improving speech discrimination 
(intelligibility) as shown by the word recognition score at 50 dB. 
Endpoint:  Comparison of the word recognition score using 
the Esteem® compared to the pre-implant aided condition. 
 
3. To determine the incidence of Serious Adverse Device Effects 
(SADE) and Adverse Device Effects (ADE) and the incidence rate 
of device failures and replacements.   
 
Endpoint: The analysis of the incidence of SADEs and device 
failures and replacements at each follow-up.  
4. To demonstrate that the incidence of facial pareses/paralysis is no 
greater than the 7% incidence experienced in the PMA clinical trial. 
       Endpoint: 
The 
analysis 
of 
the 
incidence 
of 
facial 
pareses/paralysis at 1 month follow-up.  
5. To demonstrate that the subjects’ cochlear function remains 
unchanged with the Esteem® System as shown by comparison of 
the subjects’ pre-implant baseline bone conduction threshold versus 
the subjects’ post-activation visit bone conduction threshold. 
Endpoint:  Comparison of bone conduction threshold (BC) 
using forehead placement post activation compared to the 
pre-implant BC threshold. 
 
Secondary Objectives: 
 
1. To show that the Esteem® System improves Quality-of-Life when 
compared to the baseline aided condition as shown by APHAB 
results. 
2. To gather subject feedback and comments on the use of the 
Esteem® System relative to the pre-implant hearing aid (aided 
condition) as shown by the Esteem® Questionnaire. 
 
Sponsor Contact Information: 
Envoy Medical Corporation, Inc. (EMC) 
 
4875 White Bear Parkway 
 
White Bear Lake, MN 55110 
 
Tel:  (651) 361-8000 
 
Customer Service Fax:  (651) 361-8099 
 
www.envoymedical.com 
 
 
 
 

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Changes in Revision 04 
 
Change footer revision number from Rev 03 to Rev 04   
Clarify the enrollment totals for efficacy and safety endpoints in Protocol Summary, sections 1.4, 2.2 and 
4.7 
Change sponsor address of Envoy Medical Corporation to current address 
Miscellaneous typo corrections 
 
 

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1 
INTRODUCTION 
1.1 
Device Name 
The device being evaluated in this Post Approval Study is the Esteem® Totally Implantable 
Hearing System (Esteem® System). The Esteem® has recently been approved by FDA for 
the US market under PMA P090018.  This study fulfills the requirement for one of the Post 
Approval Studies. 
1.2 
Device Description and Principle of Operation 
The Esteem® System is a totally implantable hearing system designed to improve hearing 
in subjects suffering from moderate to severe hearing loss that is sensorineural in origin. 
The Esteem® System consists of three components that are implanted in the subject:  A 
Sound Processor (SP) is implanted under the scalp over the temporal bone and is 
connected via leads to two piezoelectric transducers (called the Driver and Sensor), which 
are implanted in the middle ear.  In addition there are two components that will be used 
during the implant of the Esteem® System:  An intra-operative test system, and the 
Esteem® programmer.  The Esteem® programmer will also be used by the audiologist for 
follow-up Esteem® System management.  When the Esteem® System is activated the 
subject will receive an additional external component, the Personal Programmer.  See full 
description below. 
The Esteem® System works in the following manner:  The Sensor is placed on the incus 
bone.  This Sensor senses mechanical vibrations transmitted from the eardrum through the 
malleus and/or incus bone, then converts these vibrations into an electrical signal, which is 
sent to the SP.  The SP amplifies and filters the signal, then sends it to the Driver, which 
has been attached to the head of the stapes.  The Driver converts the modified electrical 
signal back to mechanical vibrations that is transferred to the stapes.  The stapes bone 
vibrates the oval window, which produces pressure waves in the fluid of the cochlea.  The 
cochlea converts the pressure waves to nerve impulses, which are transmitted via the eight 
cranial nerves to the brain, where they are interpreted as sound. 
Prior to implantation of the Driver and Sensor, the incus will be separated from the stapes 
at the incudostapedial joint and 1 to 3 mm will be resected from the long process of the 
incus.  This will allow the Driver to be placed directly over the stapes bone and prevent 
feedback to the Sensor that could result in poor system performance. 
The Esteem® programmer enables the physician and/or the audiologist to program each 
subject’s implanted SP to that subject’s specific audiological need.  The programmer is also 
used to interrogate the Esteem® System’s Sound Processor and provides the physician 
and/or the audiologist with diagnostic capabilities both during the operative procedure and 
during follow-up clinic visits. 
The Personal Programmer enables the subject to select from three (3) pre-set programs for 
background noise levels, to place the device on standby, and to increase or decrease the 
volume of his/her Esteem® System SP using radio frequency (RF) telemetry.  The 
Personal Programmer is battery operated and has a low battery indicator. 
The Envoy Medical Intra-operative System Analyzer (ISA) is used during the implant 
procedure to verify that the Sensor and Driver are positioned correctly. It will also be used 
at the end of the implant procedure to verify that the Esteem® System is functioning 
appropriately. 
1.2.1 
Anticipated Changes in Device 
There are no plans to change the device or the protocol during this Post Approval 
Study. 
 
 

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1.3 
Indications for Use 
The Esteem® is intended to alleviate hearing loss in patients by replicating the ossicular 
chain and providing additional gain. The Esteem® is indicated for patients with hearing loss 
that meet the following criteria: 
 
18 years of age and older 
 
Stable bilateral sensorineural hearing loss 
 
Moderate to severe sensorineural hearing loss as defined by Pure Tone Average  
(PTA) 
 
Unaided Speech discrimination scores greater than or equal to 40% 
 
Normally functioning Eustachian tube 
 
Normal middle ear anatomy 
 
Normal Tympanic Membrane 
 
Adequate space for Esteem®  implant determined via a high resolution CT scan 
 
Minimum of 30 days of experience with appropriately fit hearing aids 
 
1.4 
Justification for the Investigation 
In order to study the safety and effectiveness of the Esteem® System in a clinical 
environment, a post-approval study was requested by FDA.  This post-approval study will 
include a minimum of 45 subjects implanted by newly-trained surgeons at 5 to ten 
investigational sites followed through their 1-year follow-up visit for both safety and efficacy 
endpoints.  In addition, an extension of the PMA pivotal clinical trial conducted under IDE 
G070162 was conducted as a separate post-approval study.  That study demonstrated 
long-term safety and effectiveness through 5-year follow-up.     
1.5 
Duration of the Investigation 
The post-approval study will commence immediately upon PAS Protocol approval.  
Subjects will be followed at 1, 4 and 10-months post-activation and annually thereafter 
through 1 year.   
2 
STUDY DESIGN AND OVERVIEW 
2.1 
Trial Design 
This Post Approval Study is designed as a prospective, multi-center, non-randomized, 
clinical trial to evaluate the safety and efficacy of the Esteem® System implanted by newly-
trained surgeons.  For this trial the subject will act as his or her own control. 
This trial has been designed to meet United States’ regulatory requirements.   
Each subject will act as both the test subject and the control by being tested prior to implant 
in both the unaided and aided condition.   
2.2 
Investigational Sites and Number of Enrollments 
The post-approval study will enroll a minimum of 45 new subjects on a consecutive 
consenting basis at 5 to 10 investigational sites to be implanted by newly-trained surgeons. 
These subjects will be evaluated for both efficacy and safety endpoints. The goal will be to 
monitor 
the 
subjects 
through 
their 
one 
(1) 
year 
follow-up.  
NOTE: In order to achieve the required sample size of 109 subjects for the safety 
endpoints, data from these 45 new subjects will be supplemented by data from a 
retrospective chart review of “commercial” (non-study subjects).    
Trial Objectives 
The overall objective of the study is to evaluate the safety and effectiveness of the 
Esteem® System implanted by newly-trained surgeons in subjects suffering from moderate 
to severe hearing loss. 
 
 Primary Objectives: 
 

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1)    To demonstrate that the Esteem® System improves the speech threshold of sensitivity for 
hearing and identifying speech signals as well as or better than the pre-implant hearing aid 
(aided condition). 
Endpoint: Comparison of the speech reception threshold (SRT) using the Esteem® System 
as compared to the pre-implant aided condition. 
 
2)     To demonstrate that the Esteem® System is as effective as or better than the hearing aid for 
improving speech discrimination (intelligibility) as shown by the word recognition score at 50 
dB. 
Endpoint: Comparison of word recognition score using the Esteem® as compared to the 
pre-implant aided condition. 
 
  3)    To determine the incidence of Serious Adverse Device Effects (SADE) and Adverse Device 
Effects (ADE) and the incidence rate of device failures and replacements.   
Endpoint: The analysis of the incidence of SADEs and device failures and replacements at 
each follow-up. 
 
4)   To demonstrate that the incidence of facial pareses/paralysis is no greater than the 7% 
incidence experienced in the PMA clinical trial. 
 Endpoint: The analysis of the incidence of facial pareses/paralysis at 1 month follow-up.  
 
5)    To demonstrate that the subjects’ cochlear function remains unchanged with the Esteem® 
System as shown by comparison of the subjects’ pre-implant baseline bone conduction 
threshold versus the subjects’ post-activation visit bone conduction threshold. 
          Endpoint: Comparison of the bone conduction threshold with forehead placement compared 
to the pre-implant bone conduction threshold. 
 
Secondary Objectives: 
1) To show that the Esteem® System improves Quality-of-Life when compared to the baseline 
aided condition as shown by APHAB scores. 
2) To gather subject feedback and comments on the use of the Esteem® System relative to the 
pre-implant hearing aid (aided condition) as shown by the Esteem® Questionnaire. 
 
3 
BENEFITS/RISKS 
Sponsor and the investigators have determined that the study is justified because the potential 
benefits outweigh the attendant risks.  This has been confirmed by FDA in approving PMA 
P090018. 
3.1 
Potential Benefits 
Hearing aids, cochlear implants, and semi-implantable hearing prostheses are some of the 
technologies available for the treatment of hearing loss.  The Esteem® System has been 
developed as a fully implantable treatment option for adults who have hearing loss.  The 
potential benefits that the Esteem® System may provide include: 
 
Better fidelity of sound 
 
Elimination of ear canal occlusion 
 
Elimination of maintenance issues 
associated with hearing aids, cochlear 
implants and semi-implantable hearing 
 Improved cosmesis 
 Improved ease of communication 
 Improved audiometric thresholds 
 Improved hearing in noise 

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devices 
 
Elimination of hearing aid type feedback 
 
Elimination of intolerable ear canal 
conditions such as eczema or infections 
caused by hearing aids 
 
Ability to hear continuously throughout 
the day (24/7). 
 
Improved hearing in reverberating rooms 
 Longer battery life than hearing aids 
 
Reduction of the stigma of hearing 
impairment 
 
Improved quality of life 
 
Regain active lifestyle 
 
3.2 
Potential Risks 
 
Subjects participating in this study are subject to some potential risks and complications 
associated with the implantation and use of the Esteem® System.  The occurrence of 
adverse events may result in a revision surgical procedure, which may include device 
replacement or device removal.   
The Esteem® implant procedure is a middle ear surgery, and the risk of a potential revision 
procedure after a middle ear surgery, including the implant of the Esteem® system may be 
as high as 7%.  The revision rate for the subjects enrolled early in this clinical trial was 5% 
with an additional 2% explant rate.   
 
The potential risks and discomforts associated with the operative procedure are similar to 
those for standard mastoid operations.  Risks include but are not limited to the following: 
 
 
Bleeding 
 
Cerebral spinal fluid (fluid that 
surrounds the brain) leak and 
meningitis (brain infection) 
 
Damage to the Chorda Tympani 
branch of the facial nerve which may 
result in temporary or permanent taste 
disturbances  
 
Death 
 
Development of ear ringing (tinnitus) 
or an increase in ringing that was 
already present before the operation  
 
Drainage from ear canal 
 
Eardrum perforation/hole 
 
Hematoma/blood clot 
 
Infection of the ear 
 
Jaw soreness or stiffness  
 
Partial or complete one-sided facial 
paralysis or stimulation 
 
Partial or total loss of remaining hearing 
on implanted ear due to surgical 
procedure 
 
Physical breaking or dislocation of the 
middle ear bones  
 
Post-operative pain (everyone has 
discomfort after surgery for which we 
prescribe pain medication) 
 
Temporary external ear or incision 
numbness 
 
Transient or prolonged dizziness or 
vertigo 
 
Widening and thickening of the scar 
behind the ear (there is a small scar in 
every patient) 
 
Transient or prolonged ringing (tinnitus) 
in the operated ear 
 
There may be some potential risks and complications that are possible due to the 
implantation and use of the Esteem® System.  These risks include but are not limited to the 
following: 
 
 
Amplification of body sounds such as 
chewing or swallowing  
 
Cranial stimulation or head vibrations  
 
Decay of soft tissue or bone (includes 
erosion, necrosis, extrusion, or 
dehiscence of the wound) resulting in 
the body’s rejection of the device 
 
Device failure/malfunction 
 
Loss of attachment of leads from the 
Sound Processor or the transducers 
from the mastoid and/or ossicular chain 
bones (incus or stapes) that requires 
surgery to fix 
 
Noise, distortion, or poor fidelity  
 
Non-implant of the device due to fit or 
function of the device 

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 
Dizziness when test vibrations are 
delivered to the stapes (middle ear 
bone)  
 
Feedback/whistling or squealing from 
the device  
 
Fibrotic growth/keloid formation 
(growths around the scar tissues or 
around the device)  
 
Infection of the Sound Processor 
pocket  
 
Injury to the middle ear bones 
because of physical contact with the 
Sensor/Driver portion of the device  
 
Partial or total loss of remaining hearing 
on implanted ear due to device failure 
 
Stimulation of the chorda tympani 
branch of the facial nerve  
 
Stimulation of the facial nerve 
 
Subluxation of the stapes as a result of 
cement removal during revision or 
explantation of the Esteem®  System 
 
Transient or permanent injury to the 
hearing (auditory) nerve of the test ear 
with subsequent hearing loss due to the 
physical vibration of the stapes by the 
Driver portion of the device  
 
Accumulation of air under the scalp 
around the Sound Processor due to 
inadvertent nose blowing after the 
operation 
Potential risks to the ear include infection of the ear.  Risks specific to the middle ear 
include but are not limited to the following: 
 
Fullness or stuffy sensation in the 
ear  
 
Middle ear infection 
 
Ossicular necrosis or deterioration of 
the middle ear bones over time 
 
Hearing loss secondary to other risks 
of the middle ear 
 Reconstruction of the bony ossicular 
chain due to resection of the long 
process (arm) of the incus bone  
 
Potential risks of cochlear damage include but are not limited to the following: 
 
Damage to the cochlea (inner ear) 
due to excessive pressure from the 
Esteem System  
 
Damage to the cochlea (inner ear) 
associated with performing intra-
operative testing  
 
Excessive electrical stimulation from 
the device of the inner ear  
 
Excessive vibration of the inner ear 
 
Hearing loss secondary to other risks 
to the inner ear 
 
Insufficient stimulation of the inner ear 
Potential risks associated with anesthesia include but are not limited to the following: 
 
Neurological complications due to an 
increase in general anesthesia time 
above that normally associated with 
mastoid surgery 
 
Reaction to anesthesia 
 
Allergic reactions 
Potential risks associated with a second surgical procedure (a transcanal middle ear 
surgery) include but are not limited to the following: 
 
Disruption of the Sensor when lifting 
the eardrum 
 
Drainage from the ear canal 
 
Infection 
 
Injury to the nerve for taste 
(chordatympanineve) causing a 
temporary or permanent taste 
disturbance 
 
Pain from the surgical procedure 
 
Immediate or delayed hole(s) in the 
eardrum (perforation(s)) 
 
Reaction to anesthesia 
 
Stiffening of the eardrum 
 
 
All efforts will be made to minimize these risks by selecting investigators (includes surgeon, 
audiologist, technician, and/or research coordinator as appropriate for each site) who are 
experienced and skilled in otology.  All investigators will be trained in the placement of the 

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Esteem® System prior to the start of the study.  See Section 6.4 for Physician Training 
Plan. 
These risks can be minimized through the use of strict aseptic technique, compliance with 
this protocol and technical implant procedures, adherence to the guidelines for subject 
selection, close monitoring of the subject’s physiologic status during implant and follow-up 
procedures, and by promptly supplying Envoy Medical with all information required by this 
protocol. 
 
4 
TRIAL METHODOLOGY 
4.1 
Subject Selection 
All subjects with moderate to severe sensorineural hearing loss are potential study 
candidates.  The site is responsible for screening potential subjects and selecting those 
who are appropriate for Esteem® implant.  Subjects who meet the inclusion / exclusion 
criteria will be asked to participate in the trial. 
 
4.1.1 
Inclusion Criteria 
Subject must meet all of the following criteria to be eligible for treatment in the trial: 
a) Subject is  18 years old 
b) Subject understands the nature of the procedure and has signed the Subject 
Informed Consent Form prior to the procedure 
c) Subject is willing and able to comply with specified follow-up evaluations and 
understands the audiological test procedures and use of the Esteem® 
System. 
d) Subject has moderate to severe sensorineural hearing loss in the ear to be 
implanted defined by pure tone average air-conduction threshold level. 
e) Subject has an unaided maximum word recognition score of greater than or 
equal to 40% with recorded delivery using a phonetically balanced word list 
at SRT + 40 dB or at maximum tolerable presentation level. 
f) 
Subject is a current user of a properly functioning and appropriately fit 
hearing aid for at least one (1) month in the ear to be implanted.     
g) Subject has normally functioning eustachian tube  
h) Subject has normal tympanic membrane 
i) 
Subject has a normal middle ear anatomy 
j) 
Subject has adequate space for Esteem® System implant determined via 
fine cut temporal bone CT scan 
k) Subject is a native speaker of the English language. 
 
4.1.2 
Exclusion Criteria 
Subjects will be excluded from the trial if any one of the following criteria is met: 
a. Subject has a history of post-adolescent chronic middle ear infections, 
inner ear disorders or recurring vertigo requiring treatment, disorders 
such as mastoiditis, Hydrops or Meniere’s syndrome or disease 

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b. Subject has a history of otitis externa or eczema for the outer ear canal 
and the investigator believes this will affect the Esteem® System 
implantation 
c. Subject has cholesteatoma or destructive middle ear disease 
d. Subject has life expectancy of  two (2) years due to other medical 
conditions 
e. Subject has retrocochlear or central auditory disorders 
f. 
Subject is known to be suffering from any psychological, developmental, 
physical, or emotional disorder that the investigator feels would interfere 
with the surgery or follow-up testing 
g. Subject has a known history of fluctuating air conduction and/or bone 
conduction hearing loss over a one-year period of 15 dB in either 
direction at 2 or more frequencies (from 500 – 4000 Hz) 
h. Subject has sudden hearing loss due to unknown cause 
i. 
Subject has a history of disabling tinnitus, defined as tinnitus which 
required treatment. 
j. 
Subject is unable to adequately perform audiological testing 
k. Subject has a medical condition or undergoing a treatment that may 
affect healing and the investigator does not believe the subject is a good 
candidate for the trial. 
l. 
Subject has diabetes that is not well controlled with medication or diet 
and the investigator does not believe in his best medical judgment that 
the subject would be a good candidate for the trial 
m. Subject is pregnant at the time of device implant 
n. Subject has a history of keloid formation 
o. Subject has known hypersensitivity to silicone rubber, polyurethane, 
stainless steel, titanium and/or gold 
4.2 
Screening and Baseline 
Screening and baseline consists of a thorough evaluation of the subject’s unaided and 
aided hearing to verify that the subject meets the entrance criteria and to serve as a 
baseline.  The testing to be performed for the screening and baseline can be found in Table 
1.  All screening and baseline testing must be completed within 2 months of the Esteem® 
System implant procedure. 
The screening process will begin with a review of the Screening and Baseline Subject 
Informed Consent Form.  If the subject signs the Screening and Baseline Subject Informed 
Consent Form the subject will not be excluded from screening testing. 
The screening will continue with an Audiological Pre-Screen.  If the subject’s audiological 
criteria do not exclude him or her from the trial, the subject’s medical records will be 
reviewed to determine if the subject meets the basic screening criteria.  If the subject’s 
medical history does not exclude him or her from the trial, the Esteem® System clinical trial 
will be discussed with the subject and the subject will be asked to sign the Surgical Subject 
Informed Consent Form. 
The screening will continue with basic audiological testing and high resolution CT scan to 
further evaluate the subject’s eligibility for enrollment into the trial.  If the subject has had a 
standard of care CT scan that shows adequate space for the Esteem® System implant, 
within 6 months of study screening procedures, this data will be acceptable for use in 
fulfilling the related inclusion criterion.  This testing will consist of audiological testing in the 
unaided and aided condition.   
 
In order to be implanted with the device, the subject must have worn an appropriately fit 
hearing aid for a minimum of 30 days prior to the Esteem® System implant procedure.  An 
optimized fit for the pre-implant hearing aid will achieve insertion gain within +/- 10 dB of 
the gain recommended by the hearing aid manufacturer.  Real Ear Measurement (REM) 
will be used to validate that the subject’s hearing aid is properly fit to within +10 dB (500 Hz 

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to 4000 Hz) of this optimized gain.  If the subject meets all of the initial screening criteria, 
but does not have an appropriately fit hearing aid, the patient's hearing aid will be fit with 
the manufacturer's proprietary fitting program for the optimized fit for the patient.  The REM 
data will be recorded on the Screening Case Report Form to validate optimal fit of the 
baseline hearing aid.   
If the subject requires a new hearing aid or the subject’s own hearing aid settings were 
adjusted, the subject will need to return a minimum of 30 days later to ensure that the 
subject is well adjusted to the new hearing aid.  When the subject returns, all screening and 
baseline testing will need to be tested / re-tested.  If the subject’s hearing aid is 
appropriately fit but does NOT pass the REM enrollment criteria, and the subject declines 
to return 30 days later to repeat all screening and baseline testing as required for the REM 
criteria, the subject may still be enrolled but their audiometric data will not be included in 
the analysis of study efficacy endpoints (safety and adverse event data at least through 1-
month follow-up will still be included). 
If the subject’s hearing aid did not require adjustment, the subject can proceed with the 
remainder of the screening and baseline procedures.   
Following the screening and baseline testing, if the subject meets all of the 
Inclusion/Exclusion Criteria, the subject will proceed with the Esteem® System Implant. 
This study is a non-randomized clinical trial.  If the pure tone average (average of 500, 1K 
and 2K) for both ears is within 5 dB, it will be up to the Investigator and the subject to select 
the ear that is to be implanted.  
 
 

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Esteem®  Post Approval Study Pre-Screen Process 
Audiological Pre-
Screen 
Subject Chooses 
NOT to Sign 
Screening Informed 
Consent 
Subject Signs 
Screening Informed 
Consent 
Subject Does NOT 
Pass Audiological 
Screen 
Subject Does NOT 
Pass Medical History 
Screen 
Subject Passes  
Audiological Screen 
Subject Passes 
Medical History Screen 
Subject Does NOT 
Continue with 
Procedure 
Subject 
Visits Site 
Subject 
Reviews 
Screening 
Informed 
Consent 
No Tests are 
Performed 
Failed  
Screen  
Medical History 
is Reviewed by 
Investigator 
Failed  
Screen  
Surgical Informed 
Consent is 
Reviewed with 
Physician 
Failed  
Screen  
Subject Signs 
Surgical Informed 
Consent 
Subject is 
Scheduled for 
Surgery  

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4.3 
Surgical Procedure 
 
The surgical procedure for the implantation of the Esteem® System is outlined below.  
Subjects will be considered enrolled in the trial once they have signed the Informed 
Consent Form.  
4.3.1 
Preparation of the subject and Esteem® System placement 
a) The subject will be anesthetized. 
b) Prepare subject for intra-operative testing  
c) Ensure that a facial nerve monitor is positioned to monitor the facial nerve 
during the procedure (use of this at surgeon discretion). 
d) The replica Sound Processor may be used for determination of initial incision 
placement. 
e) The incision will be made and the ear retracted for the creation of the mastoid 
cavity.   
f) Use the replica Sound Processor to create a bed in the largest flat area of the 
temporal bone.  The bed should be positioned so that the Sound Processor will 
lie as flat as possible without rocking.  Note:  The Sound Processor bed should 
be drilled first to prevent excess bone dust from getting into the facial recess.  In 
addition, when drilling the SP bed care should be taken to prevent any 
penetration of the dura.  A thin layer of bone should remain in the bottom of the 
SP bed for the SP to rest on.  If the SP bed is drilled after the facial recess has 
been opened the facial recess and mastoid cavity should be packed to prevent 
bone dust from accumulating in the middle ear. 
g) Create a channel for placement of the Driver/Sensor leads. 
h) The facial recess will be opened to allow placement of the Driver. 
i) Throughout the procedure the surgical site should be continuously irrigated with 
antibiotic solution. 
j) Upon completion of the mastoidectomy and prior to separation of the ossicular 
chain, perform baseline test for comparison to Esteem® System implanted 
components and record results. 
k) Separate the incus from the stapes and resect approximately 1mm to 3mm from 
the long process of the incus.  
4.3.2 
Driver and Sensor Placement 
The placement order of the Sensor/Driver is at the discretion of the surgeon.  The 
order of placement will be recorded on the Esteem® System Implant Worksheet. 
a) After removing the Driver from the packaging, measure the capacitance using a 
capacitance meter.  Compare the measured capacitance of the Driver to the 
capacitance value printed on the label of the shipping container.   If the value is 
not within +/- 10% of the labeled value do not use the Driver. Record the labeled 
and pre-implant measured capacitance values. 
b) Apply the first coating of EnvoyCem™ cement to the capitulum of the stapes, 
taking care to assure complete coverage. 

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c) Attach the Glasscock Stabilizer to the cortex of the temporal bone with bone 
screws in the base. 
d) Insert the Glasscock Stabilizer in the stabilizer socket of the Driver. 
e) Position the Driver transducer tip above the stapes and secure the Driver 
housing and legs to the mastoid floor using MedCem™ cement.  After the Driver 
housing cement on the mastoid floor has set, connect the Driver transducer tip 
to the stapes using EnvoyCem™ cement. 
f) Open and remove the Sensor from the packaging, measure the capacitance.  
Compare the measured capacitance of the Sensor to the capacitance value 
printed on the label of the shipping container.  If the value is not within +/- 10% 
of the labeled value do not use the Sensor. Record the labeled and pre-implant 
measured capacitance values.   
Note: 
One Glasscock Stabilizer may be used to position both the Sensor and 
Driver.  If reusing the stabilizer and it has not been removed from the 
cortex skip to step h. 
g) Attach the Glasscock Stabilizer to the cortex of the temporal bone with bone 
screws in the base. 
h) Insert the Glasscock Stabilizer in the stabilizer socket of the Sensor. 
i) 
Position the Sensor transducer tip in the suggested incus / malleus position 
and secure the Sensor housing and legs to the mastoid floor using MedCem™ 
cement.  
j) 
After the Sensor housing bone cement on the mastoid floor has set, connect 
the Sensor transducer tip to the malleus and/or incus using EnvoyCem™ 
cement. 
k) After all bone cement has set remove the Glasscock Stabilizers and bone 
screws from both the Sensor and Driver. 
4.3.3 
Intra-operative Testing 
Once the Sensor and Driver have been positioned, testing will be performed using 
the Intra-operative System Analyzer (ISA).  This testing may be performed in any 
order at the discretion of the surgeon. 
NOTE: 
During the performance of the intra-operative testing the surgical site 
must be kept dry.  Therefore, it may be necessary to drain fluid from the surgical 
site during the testing procedure. 
4.3.3.1 
Intra-operative Driver Testing 
a) Connect the Driver to the driver cable.   
b) Check the capacitance of the Driver and compare to pre-positioning 
value.  If the value is not within +/- 10% of the labeled value remove 
the Driver and do not use.  Record the post-implant capacitance on 
the CRF. 
c) Conduct Laser Doppler Vibrometry (LDV) test to measure stapes 
displacement. 
d) Compare the Driver signal strength at 1Vrms to the acceptance 
range according to the ISA.  
e) Record the capacitance, and intra-operative test results. 

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4.3.3.2 
Intra-operative Sensor Testing 
a) Connect the Sensor to the sensor cable.   
b) Check the capacitance of the Sensor and compare to pre-positioning 
value.  If the value is not within +/- 10% of the labeled value remove 
the Sensor and do not use.  Record the post-implant capacitance on 
the CRF. 
c) Conduct the Sensor test. 
d) Measure the Sensor signal strength in volts peak-to-peak. 
e) Compare the Sensor signal strength at 100 dB to the acceptance 
range according to the ISA.   
f) 
Record the Sensor signal strength and capacitance.  
4.3.3.3 
Intra-operative System Testing 
The complete Esteem® System will be tested. 
a) Interrogate the Sound Processor prior to opening the non-sterile 
shelf carton.  If the Sound Processor does not respond to 
interrogation, do not use and return to Envoy Medical. 
The following testing will be performed after the leads have been 
connected to the Sound Processor and prior to wound closure.  The 
surgical site must be keep free of all fluids and as dry as possible during 
the system test to reliably collect valid test data.  
b) Connect the Sensor and Driver connectors to the Sound Processor.  
Verify that the lead terminal pins are completely inserted into the SP 
lead barrels (the pin will be visible past the connector block). 
c) Program the Sound Processor to perform the system test. 
d) Perform the system test at 80 dB according to the ISA. 
e) Record the system test results. 
f) 
After completion of all testing, program the Sound Processor 
volume step to “OFF” 
4.3.4 
 Placement of Sound Processor 
Prior to the Sound Processor being placed in the Sound Processor bed the wound 
will be irrigated with an antibiotic solution.  In addition if the subject is diabetic and 
the surgeon, using his best medical judgment, feels that the subject would benefit 
from an additional treatment the wound may be flushed with a 10% Fluconazole 
anti-fungal solution.  After the Sensor and Driver connectors are inserted into the 
Sound Processor, the surgeon has the option to secure the Sound Processor with 
sutures, titanium straps or Gortex strips in the previously created bed.  Verify that 
the Sound Processor fits tight and does not move.  Position the Driver/Sensor 
leads in the previously created channels and secure to prevent the leads from 
crossing, touching, or rubbing.  After all testing is complete the surgeon will close 
the incision. 
 
4.4 
Post-Procedure/Discharge 
Prior to discharge, the investigator may take an x-ray of the implanted device to visualize 
the location of the device so that leads are not accidentally cut in the event of a battery 
exchange or a system revision is required. The Investigator will also assess the subject’s 
clinical status and record any clinical events.  It is recommended that any subject that is 
diabetic would be administered an oral prophylactic antifungal treatment of either 

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Fluconazole or Voriconazole for two weeks post-operatively.  This treatment should be 
given only if in the investigator’s best medical judgment and after a careful review of the 
subject’s medical status and history. 
The Investigator/Audiologist/Research Coordinator will review the follow-up requirements 
with the subject to ensure compliance with the follow-up schedule.  Subjects will be 
reminded of the requirements for follow-up. 
4.5 
Follow-Up 
Post-implant, the subjects will be required to return for follow-up and testing of the 
Esteem® System as listed below.   
All subjects will return to the investigator/audiologist for the scheduled clinical and 
audiological follow-up visits.  Follow-up testing should be performed in the same 
clinic/laboratory as the baseline testing whenever possible.  The testing for each visit is 
outlined in Table 1.  
Due to the complexity of the device, Envoy Medical personnel may be present at the follow-
up visits in order to assist the site personnel on programming methods. 
4.5.1 
Post Implant Follow-up Visit(s)  
The investigator may schedule as many post surgical visits as he/she feels are 
necessary to evaluate each subject’s healing status.  The investigator should 
ensure proper healing of the middle ear and around the SP.  These visits may be 
scheduled as needed until the Activation Visit, at which time the protocol defined 
time frames must be followed.   
4.5.2 
Activation Visit (8 weeks  2 week post implant) 
At the Activation visit, the subject will be evaluated to ensure proper healing of the 
middle ear and around the implanted Sound Processor.  The device will be turned 
on to begin the acclimation period.  An audiogram will be performed along with an 
Envoygram to ensure that the device is providing the subject with some benefit.   
The testing required at the Activation Visit is outlined in Table 1.  
A personal programmer will be provided to the subject and he or she will be 
instructed on how to use the Personal Programmer prior to leaving the clinic. 
 
Due to the nature of Middle Ear surgery and potential requirements for multiple 
revisions, the surgical procedure may require a second procedure or “revision” to 
properly adhere the driver to the stapes. The procedure will be considered 
complete once the driver to the stapes connection has been determined to be 
successful by the surgeon. All revision surgeries will be reported as clinical 
procedure failures. 
4.5.3 
Follow-up Visits  
The subjects will return to the clinic for follow-up visits after the device is activated.   
The visits will occur at 1 month ( 3 weeks), 4 months ( 3 weeks) and 10 months 
(3 weeks) post activation. The visits will consist of the testing outlined in Table 1. 
 
 

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4.6 
Testing Requirements 
Testing requirements for the trial are listed in table 1.  
 
TABLE 1:  Minimum Screening and Follow-up Requirements 
 
Scr / 
BL 
Proc/ 
Disc 
Act 
1 Mo 
 
4 Mo 
 
10 Mo 
Informed Consent 
X 
 
 
 
 
 
Medical History 
X 
 
 
 
 
 
Audiological and Hearing Aid History 
X 
 
 
 
 
 
Current Medications 
X 
 
X 
X 
X 
X 
Adverse Events 
 
 
X 
X 
X 
X 
Device Settings 
 
 
X 
X 
X 
X 
Testing Requirements 
 
 
 
 
 
 
APHAB Questionnaire 
X 
 
 
 
X 
X 
Esteem®  Questionnaire 
 
 
 
 
X 
X 
Otoscope Exam  
(perform prior to testing) 
I/N 
 
I 
I 
I 
I 
Tympanogram 
I/N 
 
I 
I 
I 
I 
Air Conduction Thresholds 
I/N 
 
I 
I 
I/N 
I/N 
Air Conduction – Aided (Implant) Ear 
Warble Tone 
I 
 
 
I 
I 
I 
Bone Conduction Thresholds  
I/N 
 
I 
I 
I/N 
I/N 
Most Comfortable Listening Level (MCL)  
I/N 
 
I 
I 
I 
I 
Uncomfortable Listening Level (UCL)  
I/N 
 
I 
I 
I 
I 
Speech Reception Threshold (SRT)– 
unaided 
I/N 
 
 
 
 
 
Speech Reception Threshold (SRT)– aided 
I/N 
 
I 
I 
I 
I 
Word Recognition – unaided 
I/N 
 
 
 
 
 
Word Recognition – aided  
I/N 
 
I 
I 
I 
I 
Envoygram IT 
 
 
X 
X 
X 
X 
CT Scan 
X 
 
 
 
 
 
X-ray of implanted device (optional) 
 
X 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
I=Implanted Ear  
N=Non-Implant Ear 
 
 

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4.6.1 
Device Revisions / Interventions 
There is also a possibility that post-implant, a surgical intervention may be required 
to repair, replace or completely remove some or all of the components of the 
Esteem® System due to device failure, malfunction or as a result of an adverse 
event.  The surgical procedure may be performed in one of two ways: either 
through the subject’s original incision or through the external ear canal; depending 
on the scope of the intervention.  The surgical procedure may be performed under 
local or general anesthesia at the discretion of the surgeon.   
A description of the recommended procedure that will be followed for each revision 
method is listed below: 
4.6.1.1 
Mastoid Approach (through the original incision) 
 
The original incision will be opened to expose the Sound Processor 
(SP). 
 
The Driver and Sensor lead will be disconnected from the SP. 
 
The capacitance of the Driver and Sensor will be tested. 
 
The Driver and Sensor will be tested.  All or some of the intra-
operative testing may be preformed in order to evaluate the system. 
 
The test results will be evaluated to determine if the Driver and 
Sensor are functioning correctly.  If one or both are not performing as 
expected the non-functioning part will be removed and replaced with 
a new part following the standard implant techniques outlined above.  
The new part will be tested to verify correct function. 
 
The Driver and Sensor will be connected to the Sound Processor, 
system testing will be performed and the wound closed. 
4.6.1.2 
Ear Canal Revision 
This approach will only be used to give access to the Driver/stapes 
interface.  No part of the device will be removed or replaced using this 
approach.  It is possible that the bone cement may be removed and 
reapplied. 
 
An incision will be made in the ear canal close to the tympanic 
membrane (TM). 
 
The TM will be lifted away to expose the Driver/stapes interface for 
evaluation. 
 
If the bone cement requires replacement the old cement will be 
removed and new cement will be placed. 
 
Laser Doppler Vibrometer (LDV) measurements may be made. 
 
The TM will be replaced and the outer ear canal will be packed. 
All revisions will be documented in the subject CRFs. 
4.6.2 
Removal of Subjects from Study 
All subjects enrolled in this study are subject to complete clinical follow-up and will 
be included in the analysis of safety and effectiveness, as appropriate. 
A subject may be removed from the study for any of the following reasons: 
 
Subject has fulfilled Protocol Requirements 
 
Subject did not receive the implant 
 
Subject withdraws consent 
 
Subject is lost to follow-up 

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 
Subject has an inter-current illness that precludes follow-up 
 
Subject does not comply with the protocol 
 
Subject dies 
 
Investigator believes that it is in the best interest of the subject 
 
Sponsor terminates the study 
 
If the subject completes or is withdrawn from the study the reason will be recorded 
on the CRF along with any relevant information concerning any device explant, 
subject death, and autopsy. 
 
 
4.7 
Adverse Events 
 
The 109 subjects to be reported for the Adverse Event endpoint will consist of the 
45 newly-implanted subjects supplemented by data from a retrospective chart 
review of “commercial” (non-study subjects).    
4.7.1 
Definitions 
Adverse Event (AE):  An Adverse Event is any undesirable clinical event 
occurring to a subject, during a clinical trial, whether or not it is considered related 
to the investigational product.  This includes a change in a subject's condition or 
laboratory results, which has or could have a deleterious effect on the subject’s 
health or well-being, including failure of bone conduction/safety algorithm. 
Serious Adverse Event (SAE):  A Serious Adverse Event (SAE) or a Serious 
Adverse Device Effect (SADE) are events which: 
 
Results in death 
 
Is life threatening 
 
Results in persistent or significant disability / incapacity 
 
Results in a congenital anomaly / birth defect 
 
Requires or prolongs in-patient hospitalization (>24 hours) 
 
Requires intervention to prevent permanent impairment/damage 
Unanticipated Adverse Device Effect (UADE):  An Unanticipated Adverse 
Device Effect is any serious adverse effect on health or safety or any life-
threatening problem or death caused by, or associated with, a device, if that effect, 
problem, or death was not previously identified in nature, severity, or degree of 
incidence in the investigational plan or application (including a supplementary plan 
or application), or any other unanticipated serious problem associated with a 
device that relates to the rights, safety, or welfare of subjects.  NOTE:  an UADE is, 
by definition, serious in nature. 

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4.7.2 
Reporting of Adverse Events 
The procedure for reporting any AE is as follows: 
 
All Adverse events  will be documented on an Adverse Event Form 
 
The Investigator is responsible for reporting AEs to his or her IRB in 
accordance to their site’s IRB procedures.  
 
The Investigator shall report all unanticipated adverse device effect to the 
Monitor/Sponsor as soon as possible, but definitely no later than 10 days after 
obtaining knowledge of event.  
 
The Sponsor is responsible for informing the FDA, all reviewing IRBs and other 
investigators of any unanticipated adverse device effect that has occurred. 
4.8 
Device Failures and Malfunctions 
4.8.1 
Definition: A Device failure is defined as the inability of the device to perform its 
intended function.  Device failures can result from hardware/software problems or 
surgical procedure problems. 
4.8.2 
Reporting and Return: All failures and malfunctions will be documented on the 
CRF and reported in the clinical results.  Esteem® System devices that fail or 
malfunction will be returned to the Sponsor for analysis. 
If at all possible, a representative from the Sponsor will be present for the 
removal of an Esteem® System due to a failure or malfunction.  
5 
STATISTICAL ANALYSIS 
5.1 
Sample Size 
 
For the effectiveness objectives, based upon the following analysis and 0204 clinical data, 
a sample size of 45 new subjects meets the guidelines for statistical power.  For the facial 
pareses/paralysis objective with an end point of 1 month, a sample size of 109 subjects is 
required as shown below.   
 
SRT 
Based on a mean improvement in SRT over hearing aid of 10 dB and a standard deviation 
of 13 dB, 45 subjects at 1 year would provide at least 80% power for testing non-inferiority 
and superiority at a one-sided 0.05 alpha level. A margin of – 5 dB will be used for non-
inferiority and a margin of +5 dB will be used for superiority. 
 
WRS 
Based on a mean improvement in WRS over hearing aid of 22% and a standard deviation 
of 31, 45 subjects at 1 year would provide at least 80% power for testing non-inferiority and 
superiority at a one-sided 0.05 alpha level. A margin of –10% will be used for non-inferiority 
and a margin of +10% will be used for superiority. 
 
Facial Pareses/paralysis: 
Based upon a null hypothesis of 7% and a hypothesized true rate of 2% of facial 
paresis/paralysis, 109 subjects at 1 month would provide at least 80% power for testing the 
hypothesis. 
 
5.2 
Objective Analysis 
 
The following statistical analyses will be done. 

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Objective 1: To determine whether the Esteem® System improves the subjects’ threshold 
of sensitivity for hearing and identifying speech signals as well as or better than the 
pre-implant conventional hearing aid. 
Endpoint:  Comparison of the subjects’ speech reception threshold using the 
subjects’ pre-implant aided condition as compared to the Esteem®  at follow-ups 
of 4 months to 1 year. 
Criterion for Non-Inferiority- The 95% Lower Confidence Bound (LBC) for the 
mean difference between the SRT at baseline versus follow-up (μ Pre-implant aided 
– follow-up) is greater than or equal to -5 dB. 
95% LCB for μ Pre-implant aided – follow-up  >   
 
Criterion for Superiority- The 95% Lower Confidence Bound (LCB) for the mean 
difference between the SRT at baseline versus follow-up (μ Pre-implant aided – 
follow-up) is greater than +5 dB. 
95% LCB for μ Pre-implant aided – follow-up >   
Category Analysis: In addition, the results will be categorized by level of 
improvement, showing % of subjects at each improvement/unimprovement 
category compared to pre-implant aided condition with the categories of 
improved/unimproved based on the +/- 5 dB margins. 
Objective 2:  To demonstrate that the Esteem® System is as effective as or better than the 
hearing aid for improving speech discrimination (intelligibility) as shown by the 
word recognition score at 50 dB. 
 
Endpoint:  Comparison of the word recognition score using the Esteem® 
compared to the pre-implant aided condition at follow-up from 4 months to 1 year. 
Criterion for Non-Inferiority- The 95% Lower Confidence Bound (LBC) for the 
mean difference between the WRS at baseline versus follow-up (μ Pre-implant aided 
– follow-up) is greater than or equal to -10%. 
95% LCB for μ Pre-implant aided – follow-up  >   
 
Criterion for Superiority- The 95% Lower Confidence Bound (LCB) for the mean 
difference between the WRS at baseline versus follow-up (μ Pre-implant aided – 
follow-up)  is greater than +10%. 
95% LCB for μ Pre-implant aided – follow-up >   
   
Additional Analyses:  The Word Recognition Scores will be compared using the 
Thornton and Raffin (1978) published upper and lower limits for various word lists 
based upon percentage scores.   Based upon this, an analysis of the % better 
than, % equal to and % below the aided condition (HA) will be presented. 
 
Reference: 
Thornton AR, Raffin MJ. Speech discrimination scores modeled as a binomial 
variable. J Speech Hear Res 1978; 21:507-18. 
    Objective 3:   To determine the incidence rate of Serious Adverse Device Effects (SADE) and 
the incidence rate of device failures and replacements. 

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Endpoint:  The analysis of the incidence of SADEs and device failures and 
replacements at each follow-up. 
Hypotheses:  There is no formal hypothesis.  This objective is to provide an 
accurate estimate of the SADE rate and device failure and replacement rate 
associated with the Esteem® System.   
Statistical Analyses:  The incidence of SADEs and device failures and 
replacements will be estimated with the observed number of SADEs and device 
failures and replacements over the total person-months of follow-up at each 
follow-up.  The upper bound of the one-sided 95% exact binomial confidence 
interval on the SADE rate and device failure and replacement rate will be 
calculated and reported. 
 
Objective 4: To demonstrate that the incidence of facial pareses/paralysis is no greater than 
the 7% incidence experienced in the PMA clinical trial. 
Endpoint: The analysis of the incidence of facial pareses/paralysis at 1 month 
follow-up.  
Criterion for success: The 95% Upper Confidence Bound (UCB) for the incidence 
of facial paresis/paralysis (pparesis/paralysis)  is less than 7% 
95% UCB for pparesis/paralysis < 7% 
Statistical Analyses:  The upper bound of the one-sided 95% exact binomial 
confidence interval on the incidence of facial paresis/paralysis will be compared to 
7% and success declared if it is lower than 7%. 
 
Objective 5:     To demonstrate that the subject’s cochlear function remains unchanged with the 
Esteem® system as shown by comparison of the subject’s pre-implant baseline 
Bone Conduction Threshold (BCT) vs. the subject’s post activation BCT. 
Endpoint Analysis: Bone conduction will be measured with forehead probe 
placement. The Safety Algorithm as described in Attachment C, will be used for 
any Bone Conduction results outside the stability range. 
 
 
6 
ADMINISTRATIVE RESPONSIBILITIES 
6.1 
Institutional Review Board (IRB)  
This protocol and the informed consent must be reviewed and approved by each site’s IRB 
prior to obtaining written informed consent or allowing a subject to participate.  Changes to 
the protocol that may increase the risk or present new risks to the subject, or may 
adversely affect the validity of the trial, must be approved in writing by Sponsor, IRB and 
the FDA before the change is made. 
IRB approval to participate in this trial is required from each institution participating in this 
investigation.  Prior to subject enrollment, a signed copy of the IRB approval letter must be 
submitted to Sponsor certifying trial approval.  Investigators are responsible for submitting 
and obtaining initial and continuing review (at intervals not greater than once a year) of the 
trial by their IRB. 
The investigator will report to the Sponsor immediately, if, for any reason, the approval to 
conduct the investigation is withdrawn.  The report will include a complete description of the 
reason(s) for which the approval was withdrawn. 

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6.2 
Subject Informed Consent 
Prior to screening for eligibility, subjects must consent to screening and baseline testing.  
During the consent process, the scope, and the description of tests of the screening and 
baseline should be reviewed with the subject.  The subject should have the option to ask 
questions and have them answered to their satisfaction.  The process of consenting the 
subjects must be documented on the screening and baseline informed consent form. 
Prior to enrollment into the trial, subjects must consent to participate in the trial.  During the 
consent process, the scope, requirements, risks and benefits of the trial should be 
reviewed with the subject.  The subject should have the option to ask questions and have 
them answered to their satisfaction.  The process of consenting the subjects must be 
documented on the Surgical Informed Consent Form.  
The template Surgical Subject Informed Consent Form and Screening & Baseline Informed 
Consent Form for this trial is located in Attachment A.  Any adaptation of this format must 
include the elements of Informed Consent as required by 21CFR Part 50.  The Informed 
Consent used must be approved by the Sponsor and the Institutional Review Board (IRB) 
prior to its use.   
A copy of the signed IRB approved Surgical Subject Informed Consent Form and 
Screening and Baseline Subject Informed Consent Form must be retained at the 
investigational site along with the other investigational forms.  A copy of the consent form is 
to be given to the subject. 
6.3 
Confidentiality 
All information and data sent to Sponsor concerning subjects or their participation in this 
trial will be considered confidential by the Sponsor.  Only authorized Envoy Medical 
personnel and their designees (including contract research organizations), advisory 
committees, Investigators at other sites and IRBs will have access to these confidential files 
and have the right to inspect and copy all of the records pertinent to this trial.  This may 
include medical information gathered prior to the onset of this trial.  Authorized FDA 
personnel also have the right to inspect and copy all records pertinent to this trial.  All data 
used in the analysis and reporting of this evaluation will be without identifiable reference to 
the subject.   
Data collected and stored at the Sponsor will be free of identifying information of the 
subject including subject names and medical records numbers. 
In order to comply with the Health Insurance Portability and Accountability Act (HIPAA) that 
became effective April 14, 2003 in the US all subjects enrolled in the trial will be required to 
provide authorization to disclose Protected Health Information (PHI). 
6.4 
Investigator Training 
All investigators chosen to participate in the Esteem® System Post Approval Study are 
qualified by training and experience in otolaryngology therapy and surgery and have 
special expertise in the field of clinical research relating to the trial. 
Sponsor will schedule training on the surgical procedure for each of the participating 
investigators.   
Training will consist of a discussion of the scientific basis for the Esteem® System, 
indications for the device, pre-operative assessment of temporal bone CT scan, the 
sequence and positioning of the Driver and the Sensor.  The training will include a 
discussion on the programmable features of the Sound Processor.  Work in the temporal 
bone lab for hands on experience with the mastoidectomy; positioning the Sensor and 
Driver; and implantation of the Envoy Sound Processor will be included as part of training.  
Each participant will implant approximately 2 Esteem® Systems in temporal bones during 
training. 
In addition, all site personnel will be trained on the clinical trial protocol, the CRF 
completion procedures, the regulations pertaining to conducting clinical trials, study 
processes, device handling, and the Esteem® System programmer. 

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The audiologists at each site will be trained on the use of the Esteem® Programmer.  This 
training will include a discussion on the programmable features of the Sound Processor.   
In addition, a representative from Envoy Medical will be present at all of the implant 
procedures to perform intra-operative testing and advise the investigators if needed, and at 
the initial clinical follow-ups to answer any questions and help set up the device program 
with the site audiologist.   
All training will be documented in the clinical site files at the sponsor. 
6.5 
Investigators Responsibilities 
In accordance with FDA regulation 21 CFR Part 812 the investigator is responsible for 
ensuring that the investigation is conducted according to this protocol and that signed 
informed consent is obtained from the subject prior to his inclusion in the study.  It is the 
investigator’s responsibility to ensure that all staff assisting with the trial have appropriate 
qualifications, are fully instructed on the trial procedures and will respect confidentiality. 
6.6 
Data Monitoring and Quality Control 
6.6.1 
Training 
The training of appropriate clinical site personnel will be the responsibility of 
Sponsor.  To ensure uniform data collection and protocol compliance, personnel 
from Sponsor will review the Investigational Plan, techniques for the identification 
of eligible subjects, instructions on data collection, methods for soliciting data from 
alternative sources, and schedules for follow-up with the research coordinator and 
audiologist.   
6.6.2 
Case Report Forms (CRFs) 
CRFs will be used to collect all subject data during the trial.  CRFs will be 
monitored following the guidelines established by Sponsor’s Standard Operating 
Procedures (SOPs). 
6.6.3 
Data Reporting 
All data should be recorded on the site’s standard source documentation. 
The investigator, or an individual designated by him/her, is responsible for 
transferring the information to the appropriate CRFs.  The data on each CRF must 
be legibly handwritten with a blue/black ballpoint pen.  The investigator is 
responsible for the quality of the data collected and recorded during the trial.   
The investigator is required to sign the CRF on the appropriate page(s) to verify 
that he/she has reviewed the recorded data.. 
  
6.6.4 
Data Review 
All CRFs will be reviewed for completeness and clarity upon receipt by Sponsor.  
Missing or unclear data will be requested as necessary throughout the trial.  
Sponsor will request further documentation such as physician procedure notes 
when SAEs, and/or malfunctions are observed and reported. 
Data entry and development of the primary database for the trial will be performed 
by Sponsor or their designee(s).  Sponsor or designee(s) will also be responsible 
for auditing the database and confirming the overall integrity of the data. 
Sponsor or designee will provide clinical monitoring, including review of CRFs and 
parity checks with the source documentation including operator worksheets 
retained with CRF documentation and hospital charts. 

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All clinical sites will be monitored routinely for timeliness of CRF submission to 
Sponsor.  Any evident pattern of non-compliance with respect to the timeliness will 
initiate remedial actions.  If corrective actions are not subsequently undertaken, the 
clinical site may be withdrawn. 
To this end, the Principal Investigator must permit inspection of the trial files and 
subject CRFs by such representatives and/or responsible government agencies. 
 
6.7 
Record Maintenance 
6.7.1 
Records 
Records to be maintained by the investigator in a designated clinical trial 
administrative file include: 
 
Clinical trial investigational plan and all amendments 
 
Signed clinical trial agreement 
 
IRB approval letter(s) including informed consent 
 
IRB membership list or compliance assurance statement 
 
Correspondence relating to the trial 
 
Curriculum Vitae (CVs) for all investigators (Principal and Co-
investigator), audiologist and research coordinator 
 
Site personnel signature list 
 
Sponsor personnel sign-in log 
 
Blank sets of CRFs and instructions for completion 
 
Subject enrollment log 
 
Investigational device inventory log with invoices, including: date, 
quantity, serial numbers of all devices, and identification of all 
persons the device was used on (subject identification log) 
 
Log of all devices returned to the Sponsor and the reason for the 
return 
 
Device manual(s) and/or Instructions for Use (IFU) 
 
 
7 
REPORTS (INCLUDES ANNUAL REPORTS, FINAL REPORTS FROM INVESTIGATOR AND 
SPONSOR) 
The following records must be maintained for each subject enrolled in the trial: 
 
Signed Esteem® System Subject Informed Consent Form 
 
All completed CRFs 
 
Record of and supporting documentation for any AEs. 
 
Procedure reports, nursing notes, and subject office files 
 
Records pertaining to subject death during the investigation 
(including death records, death certificate, and autopsy report, if 
performed) 
Sponsor recommends that the investigator retain copies of procedure reports, 
procedure nursing notes, audiologist’s reports and the results of any procedures 
that occur post trial procedure. 
7.1.1 
Reports 
Investigators are required to prepare and submit to Sponsor complete, accurate 
and timely reports on this investigation when necessary. 

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Records and reports will remain on file for a minimum of two (2) years after the 
completion/termination of the investigational trial.  They may be discarded upon 
notification by Sponsor.  To avoid error, the principal investigator should contact 
Sponsor before the destruction of any records and reports pertaining to the trial to 
ensure they no longer need to be retained. 
In addition, Sponsor should be contacted if the principal investigator plans to leave 
the investigational site so that arrangements can be made for transfer of records. 
7.1.2 
Investigator’s Final Report 
Upon completion or termination of the Esteem® System clinical trial, the principal 
investigator must submit a final written report to Sponsor and their IRB.  The report 
must be submitted within three (3) months of completion or termination of the trial. 
7.2 
Investigational Site Monitoring Procedure 
Envoy Medical will serve as the Sponsor of the Esteem® System clinical trial, and Envoy 
Medical or their designee will monitor the trial according to Envoy Medical’s Standard 
Operating Procedures (SOPs) and specific FDA regulations.   
 
7.3 
Labeling:  Instructions for Use 
Copies of the proposed Instructions for Use for the Esteem® System are included as a 
separate document.   
7.4 
Deviations from Protocol 
The investigator shall not deviate from the protocol without the prior written approval of 
Sponsor except in medical emergencies or in unforeseen, isolated instances where minor 
changes are made that will not increase the subject’s risk or affect the validity of the trial.  
In medical emergencies, prior approval for protocol deviations will not be required, but 
Envoy Medical Personnel or their designee must be notified within five (5) working days of 
the incident.  All protocol deviations must be documented as to the nature of the deviation 
and the reason for the deviation on the appropriate CRF. 
7.5 
Investigational Site Termination 
Envoy Medical reserves the right to terminate an investigational site for any of the following 
reasons: 
 
Failure to secure subject informed consent 
 
Failure to report UADEs within 10 days of knowledge of 
the event 
 
Repeated protocol violations 
 
Repeated failure to complete case report forms 
 
Failure to enroll an adequate number of subjects 
 
Loss of or unaccounted for investigational product inventor

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ATTACHMENT A: Safety Algorithm 
 

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Bone Conduction/Safety Algorithm 
Introduction 
Bone conduction (BC) using forehead probe placement will be the primary test for cochlear function 
stability.  While forehead placement will minimize some of the test variability issues associated with the 
mastoid probe placement as detailed in IDE G000321, there remains the possibility that BC test-retest 
variability may result in test results outside the ±10 dB limits due to equipment limitations and probe 
placement.  As an improvement over the methods used in IDE G000321, the Safety Algorithm has been 
refined for use in this new clinical trial.  In addition to bone conduction, the EnvoyGram function will be 
used as an in-situ audiogram to directly stimulate the cochlea.  This method will be more accurate and a 
better indicator of cochlear stability than the previous EnvoyGram tests where testing done at implant was 
used to predict future performance. 
 
The EnvoyGram IT 
In addition to the programmable parameters used to affect the incoming signal, the Sound Processor has 
an internal tone generator that can be accessed through the Esteem®  Programmer in a test mode called 
the EnvoyGram IT (EnvoyGram In-situ). 
Simply put, the EnvoyGram IT is an in-situ audiogram utilizing the Driver to test cochlear function. When 
entering this test mode, the Sensor is deactivated.  The Esteem®  Programmer software allows the 
audiologists to select a frequency in the range 250 to 4000 Hz and amplitude in the range 55 to 119 dB 
SPL.   The Sound Processor synthesizes and delivers a pure tone signal to the Driver to induce known 
vibrations directly into the cochlea. There are twelve steps of amplitude. Each step provides a 4 - 6 dB 
increase over the previous step.  The typical EnvoyGram IT levels are based on: 
a. a typical intact chain displacement of 40 nm at 100 dB for frequencies below 1 kHz (Validated 
per ASTM F 2504 and EMC 003798-001),  
b. a typical Model 7502 Driver displacement in temporal bones of 88 nm/V (Validated per EMC 
003798-001), and  
c. a typical SP tone output for each volume and tone setting (Validated per EMC 003788-101 
and EMC 003872-001). 
Each patient’s intact chain has a unique displacement profile.  During implant of the Esteem® , intact 
chain data is measured and recorded to provide a normalization factor for the EnvoyGram IT. 
Intra-operative data, ASTM F 2504, and temporal bone studies at Envoy (i.e. EMC 003798-001) all 
indicate that patient-to-patient variability of intact chain displacement is at least ±6 dB.  ASTM F 2504 
cites a 95% confidence interval of ±6 dB in temporal bones.  Clinical experience has also shown that 
accurately quantifying the intact chain displacement of each patient in a live surgical field is also limited to 
approximately ±6 dB, due to presence of fluid in the middle ear space, available LDV laser angle, etc. 
 
The EnvoyGram IT test protocol is similar to that of an audiogram. The intact-chain measurements are 
recorded on the Procedure and Discharge CRF (EMC 003900-003) and entered into the EnvoyGram IT 
by the audiologist.  The test methodology is performed consistent with the Hughson-Westlake procedure.  
A signal is presented at the prescribed amplitude and frequency. If the subject acknowledges the signal, 
the intensity level is decreased two steps (10 - 12 dB). If that signal is not acknowledged, the intensity 
level is increased one step (6 dB), thus determining a threshold. This threshold provides a measure of 
cochlear function independent of the external auditory mechanism.   
 
EnvoyGram IT SPL levels are customized to the patient by taking into account each patient’s IC data.  
For instance, a patient with typical 40 nm IC displacement at 100 dB will have levels from 55 to 117 dB, 
but a patient with stiff 20 nm IC displacement at 100 dB will have levels from 61 to 123 dB.  The table 
below lists the EnvoyGram levels for a) a typical intact chain displacement of 40 nm at 1.0 kHz, 100 dB 
SPL, b) an intact chain displacement of 20 nm at 1.0 kHz, 100 dB SPL, and c) an intact chain 
displacement of 80 nm at 1.0 kHz, 100 dB SPL. 
 
Table 1: EnvoyGram IT levels in Esteem®  Programmer after intra-operative IC data 
entry.  EnvoyGram IT levels are listed in dB SPL and are automatically calculated in 

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the Esteem®  Programmer for each patient’s IC data collected during implant 
procedure.  These are the levels available for each of the test frequencies. 
 
Typical (40nm IC @ 100dB SPL) 34 
40 
46 
52 
58 
64 
70 
76 
82 
88 
94 
100 
Stiff (20nm IC @ 100dB SPL) 40 
46 
52 
58 
64 
70 
76 
82 
88 
94 
100 
106 
Loose (80nm IC @ 100dB SPL) 28 
34 
40 
46 
52 
58 
64 
70 
76 
82 
88 
94 
 
Since the EnvoyGram IT levels are calibrated to each patient, the “predicted” EnvoyGram IT thresholds 
are equal to the baseline pre-implant unaided audiogram for each test frequency.  For instance, a patient 
with 55 dB baseline air conduction threshold at 1 kHz and 80 nm measured IC would have a predicted 
EnvoyGram IT of 58 dB at 1 kHz (first level above baseline unaided threshold of 55 dB).  
 
Bone Conduction/Safety Algorithm 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
Safety Algorithm Explanation: 
 
The first level of the safety algorithm will use standard bone conduction (BC) thresholds.  Bone 
conduction thresholds are measured in the implanted ear at 0.5, 1.0, 2.0, and 4.0 kHz at baseline and 
follow-up visits.  If less than two (2) of the follow-up thresholds are more than 10 dB greater than the 
baseline thresholds, then the individual test frequencies are evaluated.  At each test frequency, if the 
follow-up threshold is less than 20 dB greater than the baseline threshold then the algorithm is considered 
complete, with a conclusion that no change cochlear function occurred.  However, if at least two (2) of the 
thresholds have increased more than 10 dB or if any individual threshold has increased by 20 dB or more, 
then the EnvoyGram data is evaluated. 
  
The second level of the safety algorithm will use EnvoyGram thresholds.  Baseline unaided air conduction 
pure tone thresholds at 0.5, 1.0, 2.0, and 4.0 kHz are measured at baseline.  Similarly, EnvoyGram 
thresholds are measured in the implanted ear at 0.5, 1.0, 2.0, and 4.0 kHz at follow-up visits.  Based on 
the intra-operative intact chain data, an EnvoyGram equivalent dB threshold is calculated for each of the 
four test frequencies.  If less than two (2) of the follow-up EnvoyGram thresholds are more than 10 dB 
greater than the baseline thresholds, then the individual test frequencies are evaluated.  At each test 
frequency, if the follow-up EnvoyGram threshold is less than 20 dB greater than the baseline threshold 
Bone Conduction 
Testing at 0.5, 1.0, 
2.0, and 4.0 kHz 
Measure  
EnvoyGram at 
0.5, 1.0, 2.0, and 
Are 
at least two 
points more than 
10 dB greater 
than 
baseline
Is 
any   
frequency  
20 dB greater 
than 
baseline 
?
No Change 
in  
Cochlear 
Done 
NO 
NO 
YES 
YES 
Is 
any   
frequency  
20 dB greater 
than 
baseline 
?
No Change 
in 
Cochlear 
Done 
NO 
NO 
YES 
YES 
Change in 
Cochlear 
Function 
Done 
Are 
at least two 
points more than 
10 dB greater 
than 
baseline

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then the algorithm is considered complete, with a conclusion that no change in cochlear function 
occurred.  However, if at least two (2) of the EnvoyGram thresholds have increased more than 10 dB or if 
any individual EnvoyGram threshold has increased by 20 dB or more, then the algorithm is considered 
complete with a conclusion that a change in cochlear function occurred. 
 
For patients with moderate to severe sensorineural hearing loss, non-responses (NR) are not uncommon 
during bone-conduction testing.  If an NR occurs during baseline bone conduction testing, that test 
frequency is not evaluated (for the same patient) in the follow-up bone conduction portion of the safety 
algorithm.  However, if an NR occurs during follow-up bone conduction testing (and is not preceded by a 
baseline NR at the same test frequency), the corresponding EnvoyGram threshold is substituted at the 
bone conduction NR test frequency.