Introduction
The ExVent is an optional accessory to the O2Vent Optima mandibular advancement device (MAD) and provides oral Expiratory Positive Airway Pressure (EPAP). The oral EPAP provided by the ExVent accessory is designed to augment the OSA therapy provided by the O2Vent Optima.

Methods
This is a prospective, open-label, single-arm study conducted at 3 sites. Subjects who have been diagnosed with mild to moderate OSA (i.e., AHI ? 5 and ? 30) were included. The subjects completed a PSG study to obtain the baseline AHI and confirm a diagnosis of mild to moderate OSA.Subsequent to the Home Use Phase subjects underwent an in-lab PSG sleep night while using the O2Vent Optima + ExVent.

Primary Outcome Measure: Change in AHI between baseline and the AHI measured during the in-lab PSG sleep night using O2Vent Optima + ExVent.

Results
Patients with mild to moderate OSA were treated with Optima MAD and ExVent for 3 months at 3 different sites in North America. Preliminary data analysis demonstrated that treatment with Optima MAD and ExVent reduced AHI from 13.5±6.4/hr to 6.6±4.5/hr (p< 0.05), average 58% reduction in AHI. The lowest oxygen during sleep increased from 84.6±2.7% to 88.6±2.9% (p< 0.05). Overall success rate (>50% reduction in AHI) with treatment was 80%. 

Conclusion
The clinical trial confirmed successful treatment with combined use of O2Vent Optima MAD and oral Expiratory Positive Airway Pressure accessory - ExVent in patients with mild to moderate OSA. Treatment was well tolerated with no excessive adverse effects.