This is a prospective study of the Attune Sleep Apnea System for the treatment of obstructive sleep apnea. The objective of the study is to demonstrate safety and effectiveness of the Attune Sleep Apnea System to support FDA marketing clearance of the device.

Inclusion Criteria:

1. Subject is between the ages of 18 and 80.
2. Diagnosis of OSA, based on ODI 10-60 (as assessed per home screening night).
3. Subject is fluent in English and understands the Study protocol and is willing and able to comply with Study requirements and sign the informed consent form.
4. BMI < 40.
5. Subject has a least one molar in each of the four quadrants of the mouth (right upper, right lower, left upper, and left lower).
6. Subject has proper mouthpiece fit, as assessed by home screening night (See section 8.3).

Exclusion Criteria:

1. OSA treatment within two weeks prior to Medical/Dental screening visit.

2. Poor nasal patency as evidenced by Peak Nasal Inspiratory Flow (PNIF) less than 75 l/min (assessed at baseline medical visit). In addition, any ongoing process or condition that limits nasal breathing or indications thereof, including: obligate mouth-breathing, persistent blockage of one or both nostrils resulting in the inability to sleep with the mouth closed, chronic nasal congestion, chronic allergic rhinitis, and intermittent allergic rhinitis that does not respond to non-sedating/non-stimulating medical therapy.

3. Oral cavity infection or any other oral or dental condition or problem that would limit subject use of the Attune Sleep Apnea System (e.g. dentures, loose tooth/teeth, temporomandibular joint (TMJ) conditions, or any oral or dental condition that the Investigator believes could be exacerbated by the Attune Sleep Apnea System.

4. Prior use of the Attune Sleep Apnea System.

5. History of any OSA surgical treatment including uvulopalatopharyngoplasty surgery (UPPP), maxillomandibular advancement surgery (MMA), radio frequency (RF) ablation treatment, palatal stent devices, etc.

6. Current use or use within the previous 2 weeks of medications or other agents that may affect sleep or PSG, including:

   1. Hypnotics, anxiolytics, anticonvulsants, sedating antihistamines, stimulants, sedating antidepressants or other medications likely to affect neurocognitive function and/or alertness. Patients on stable selective serotonin reuptake inhibitor (SSRI) therapy for > 3 months and who are expected to remain on therapy for the Study duration, may continue SSRI treatment.
   2. Consumption of > 500mg caffeine per day (e.g. > 8 cola-type beverages, > 5 cups of coffee).
   3. Any known illicit drug use or abuse within the past year, or failure to pass drug urine screen test, or alcohol breathalyzer test with result over 0.05% BAL.
   4. Smokers who smoke during the night (interference with PSG).

7. Any concomitant diagnosed or suspected sleep or chronic neurological disorders, other than OSA, including insomnia, and central sleep apnea.

8. Currently working nights, rotating night shifts, planned travel across four or more time zones required during Study period, or within two weeks prior to Study enrollment, or sleep schedule not compatible with sleep lab practices.

9. Potential sleep apnea complications that, in the opinion of the investigator, may affect the health or safety of the participant, including: low blood oxygen, recent near-miss or prior automobile accident due to sleepiness, reported history of severe cardiovascular disease (including NYHA class III or IV heart failure, CAD with angina or MI/stroke in past 6 months, uncontrolled hypertension or hypotension, cardiac arrhythmias), reported respiratory disorders, or use of medication or other treatment which may pose additional risk to the subject or confound the results of the Study.

10. Female subjects who are pregnant or intend to become pregnant during the study period.

Baseline Demographics and Characteristics are presented for the Safety Cohort

Adverse events were collect at screening, control and treatment PSG, 7 days, 14 days, 21 days, 28 days and after the final treatment PSG.