top of page

ProSomnus non-inferior to CPAP therapy for the treatment of moderate to severe OSA

The First Line Obstructive Sleep Apnea Treatment study (FLOSAT) clinical trial assessing ProSomnus, a CPAP alternative for the treatment of obstructive sleep apnoea (OSA), has reported the device is effective and non-inferior to CPAP, as a first-line treatment for moderate to severe OSA. The findings, presented at the ProSleep 2023 Users Conference, indicate that the trial is on track to achieve all endpoints.

FLOSAT is an ongoing, prospective, independent, head-to-head study comparing the effectiveness of precision obstructive apnoea treatment (OAT) as first-line treatment versus CPAP therapy. ProSomnus EVO devices are being used exclusively for the precision OAT arm of the study. A total of 136 patients with moderate and severe OSA were included in the study.


Designed and conducted by The Antwerp University Hospital (UZA), the primary endpoints of FLOSAT are to evaluate the overall effectiveness of OAT as a first-line treatment for OSA, compare the overall effectiveness of OAT with that of CPAP and evaluate patients’ preference. A total of 136 patients enrolled in FLOSAT, all with moderate to severe OSA, body mass index less than 35 kg/m2, and central AHI less than 30% of total AHI, and all of whom had not received any previous OSA therapy and were eligible for OAT. After completing three months of first-line treatment with OAT followed by three months of CPAP, participants are asked which therapy they prefer.


Key findings to date include:

  • Precision OAT was effective among 90% of moderate and 85% of severe OSA patients

  • Precision oral appliance therapy was preferred by patients, with 98% continuing therapy at three months versus 22% discontinuing CPAP therapy over the same period of time

  • In an intention to treat analysis factoring efficacy and adherence, precision OAT (ProSomnus) demonstrated twice the mean disease alleviation as CPAP

“The FLOSAT study was designed to evaluate whether precision Oral Appliance Therapy could be utilized for the very practical and emergent issue of patients with OSA who could not access CPAP due to the recall,” explained Professor Olivier Vanderveken, Antwerp University Hospital. “The preliminary results of this study indicate that precision oral appliances are an effective and patient preferred treatment option, which is particularly relevant for the growing number of sleep clinicians practicing the P4 approach to making medicine more predictive, preventive, personalised and participatory.”


An additional observation from FLOSAT is the performance of precision OAT among severe OSA patients, in the context of data reported for hypoglossal nerve stimulation (HNS). Using the same criteria for efficacy – an AHI < 20 and a 50% improvement – 85% of severe OSA patients were successfully treated with non-invasive precision OAT. Clinical studies for the surgically implanted HNS devices, such as the STAR trial, report success in the range of 66% even with patient selection and the exclusion of concentric collapse patients. In July, ProSomnus announced plans to design a head-to-head clinical trial comparing precision OAT and HNS in treating patients with severe OSA.

Patients are actively being enrolled in the Severe OSA Study, a multi-centre, prospective, clinical trial designed to demonstrate the safety and effectiveness of ProSomnus devices for the treatment of severe OSA and apply for FDA label expansion.


“The updated data and analysis from FLOSAT is validation that precision oral appliance therapy with ProSomnus devices is an effective front-line treatment for moderate to severe OSA,” said Len Liptak, Co-Founder and Chief Executive Officer of ProSomnus. “This is an important finding. Each year millions of people worldwide are diagnosed with moderate to severe OSA. An estimated 40% of them refuse CPAP. Over two and a half million people have been impacted by the recent CPAP recall and seek alternatives. The results of this study indicate that precision OAT with ProSomnus devices is an effective, and preferred, option for these patients.”

bottom of page