Hyoid Suspension to the Mandible for the Treatment of Obstructive Sleep Apnea

Obstructive sleep apnea (OSA) has become a major heath problem in the United States. With
prevalence in middle-aged adults of 2 to 4% of the population, untreated OSA has been
implicated in increased risk for cardiovascular disease, including hypertension and heart
failure.

The first line and most common treatment for OSA is continuous positive airway pressure
(CPAP) treatment, utilized by an estimated 3 million Americans. CPAP is effective in reducing
the AHI if used properly. However, the nasal mask required for CPAP during sleep leads to
poor acceptance and compliance rates. Published studies on CPAP have shown that only 58 to
80% of patients accept CPAP therapy,, and further 65 to 90% of these patients exhibit
long-term compliance with CPAP. Additionally, there are many patients who would choose other
therapy besides CPAP.

Patients cite a number of issues with CPAP, namely discomfort and inability to sleep while
connected to an air pump. Auto-titrating CPAP, heated and humidified air, and bi-PAP
(different pressures on inspiration and expiration) have improved patient compliance, but
there remains a significant unmet clinical need.

It is widely accepted that the region behind the tongue is a major site of collapse during
obstructive sleep apnea. In fact, there are many surgical procedures performed currently to
address tongue base collapse. These include: RF ablation (Somnoplasty) of the tongue base;
genioglossus advancement; Medtronic's Repose system for tongue base suspension; hyoid
suspension; and maxillomandibular advancement (MMA). The change in airway dimension after MMA
surgery on the lateral cephalograph is presented in Figure 1.

One of the principal mechanisms of effect of MMA surgery is to move the base of the tongue
and the attached structures forward. Hyo-mandibular suspension has been previously studied as
a treatment for OSA and has shown to be highly effective.

This is a prospective, multi-center, registry during which 30 subjects with OSA will be
considered for hyo-mandubular suspension treatment. After obtaining informed consent and
meeting all inclusions and exclusion criteria, subjects will be treated using the Encore
System. Subject follow-up with the physician or nurse will occur at one (1) week, one (1)
month, three (3) months, and twelve (12) months.

This study will assess the effectiveness of hyoid suspension in reducing the apnea-hypopnea
index (AHI), and improving the Epworth Sleepiness Scale (ESS), snoring (VAS) and functional
outcome (FOSQ) for the treatment of obstructive sleep apnea (OSA). In addition, the study
will evaluate the effect that the change in hyoid position has on the airway anatomy.

Inclusion Criteria:

1. Documented diagnosis of moderate or severe obstructive sleep apnea (AHI between 20 and
60/hour) evaluated with a sleep study within 12 months prior to the planned procedure

2. Age ≥ 20 and ≤ 65 years old

3. Body Mass Index (BMI) ≤ 36 (kg/m2)

4. Patient has been offered CPAP and has refused or failed to continue CPAP treatment or
is noncompliant with CPAP

5. Significant airway narrowing while mild posterior is pressure applied to hyoid bone

6. Evidence of hypopharyngeal obstruction via pharyngoscopy

7. Signed informed consent to participate in this clinical study

Exclusion Criteria:

Patient History

1. Prior OSA surgery (uvulopalatopharyngoplasty [UPPP], tonsillectomy and nasal surgery
are acceptable)

2. Active systemic infection

3. Allergy to any medication used during implantation

4. Previous history of neck or upper respiratory tract cancer

5. Radiation therapy to neck or upper respiratory tract

6. Significant dysphagia or speech disorder Anatomical Considerations

1. Identified obvious palatal stenosis 2. Enlarged tonsils (3+) 3. Anatomy unable to
accommodate the implant

Other

1. Other medical, social or psychological problems that, in the opinion of the
investigator, preclude patient from receiving this treatment, as well as the
procedures and evaluations pre- and post-treatment

2. Enrollment in another pharmacological or medical device study that may effect or bias
the results of this clinical study

3. Unable and/or not willing to comply with treatment follow-up requirements

4. Pregnancy (Female subjects of childbearing potential must have a negative pregnancy
test prior to enrollment.)

5. Lack of insurance coverage for procedure and PSG follow up and unwillingness to self
pay

6. Unwilling or unable to give signed informed consent