In Battle to Treat Obstructive Sleep Apnea, Two Companies Forge AheadIn Battle to Treat Obstructive Sleep Apnea, Two Companies Forge Ahead

The gold stadard in treating obstructive sleep apnea, a sleep disorder where breathing stops and starts during sleep, is the continuous positive airway pressure system.

The problem is that patients are turned off by the cumbrous CPAP mask and other related equipment, and many simply don't comply with the therapy.

Three U.S. companies were pursuing an alternative treatment that would involve implanting a device and providing mild electrical stimulation to the upper airways - ImThera Medical, Apnex Medical and Inspire Medical Systems. But two - ImThera and Inspire have forged ahead - while Apnex Medical closed down earlier this year after the company deemed it unlikely that it would meet a primary endpoint in its clinical trial. Apnex had reportedly raised $50 million from wellknown investors like NEA (New Enterprise Associates, Domain Associates and others. 

On Monday, San Diego-based ImThera Medical announced that it has completed enrollment in nine medical center in five countries where the company's aura6000 leep Therapy System for the treatment of moderate to severe obstructive sleep apnea in 57 patients. The date for the study's completion is September 2014.

"We are excited to be the first U.S. center to implant subjects in this landmark clinical study," said SR. Michael Friedman,  rofessor of Otolaryngology and Chairman Sleep Surgery Section at Rush University Medical Center, Chicago and a study investigator, said in a news release. "The surgeries were simple to perform and took under 60 minutes. Patient satisfaction with the therapy is high and early results are very promising."

Inspire Medical is ahead of its San Diego-based competitor with an ongoing trial that will be complete in March. The number of patients enrolled is 900, according to ClinicalTrials.gov. While Inspire is pursuing regulatory approval in the U.S., the company's device is commercially available in certain parts of Europe.

Despite the fact, that both companies use neurostimulation to control OSA, there are key differences between the technologies.

ImThera's technology involves stimulating mutiple areas of the hypoglossal nerve through electrodes and the idea is to maintain muscle tone so that the tongue doesn't fall backwards into the throat, which obstructs breathing during sleep.

Inspire Medical also stimualtes the tongue, but only the largest muscle within it and not multiple areas within the tongue. The system also has a mechanism to sense respiration using uses a pulmonary pressure sensor and thereby adds another sensing lead to the neurostimulation therapy. 

Given Apnex's shuttering these two companies will be at the forefront of gaining U.S. regulatory approval and convincing patients and doctors looking for an alternative to the burdensome CPAP masks to picks their therapy. More than 18 million adults are estimated to suffer from obstructive sleep apnea.  

[Featured Photo Credit: iStockphoto.com user  lisegagne]

-- By Arundhati Parmar, Senior Editor, MD+DI
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