Millions of Americans suffer from sleep apnea, a disorder in which the patient repeatedly stops breathing during sleep. Sleep apnea occurs when the tongue or throat muscles close off the airway during sleep, or the brain fails to properly signal the muscles that control breathing. Patients may stop breathing as many as one hundred times per night. Sleep apnea is linked to poor sleep quality, impaired cognitive function, headaches, weight gain, stroke, increased risk of heart problems such as coronary artery disease and hypertension, and death.
Sleep apnea is typically treated with a Continuous Positive Airway Device (CPAP), an air pump and mask that the patient wears during sleep. However, the device can be uncomfortable for patients to use, and it has a poor compliance rate—by some estimates, as low as 40 to 50 percent. There is an unmet clinical need for effective sleep apnea devices that encourage compliance.
Earlier this month, Apnex Medical announced positive preliminary data from a first-in-man clinical trial of an implantable device to treat obstructive sleep apnea (OSA), a form of the disorder caused by blockage of the airway. The study found that the device reduced the severity of OSA by 50 percent, according to an index that measures the number of times breathing is prevented or restricted during sleep. Patients reported improved quality of life, and the device was found to be well-tolerated. The Apnex Hypoglossal Nerve Stimulation (HGNS) system is designed to automatically activate an upper airway muscle to prevent the tongue from blocking the airway during sleep. The device automatically turns on during sleep and turns off when the patient is awake.
Apne Medical is one of several companies developing devices to treat sleep apnea. Another company working in this space is LinguaFlex. The LinguaFlex LTR is an implantable device injected into the tongue, made to manipulate the upper airway and eliminate the root cause of sleep apnea. Additional companies working on sleep apnea therapies include Pavad Medical and Apneon.
In related news, VIVUS announced in January that its anti-obesity drug candidate Qnexa reduced sleep apnea events by 69 percent in a small clinical trial. It may be that the reduction in sleep apnea events is due to weight loss, as obesity is associated with the sleep disorder. Either way, VIVUS has only submitted Qnexa to the FDA as a weight-loss drug at this time.
Before sleep apnea can be treated, it must be diagnosed. The majority of obstructive OSA cases go undiagnosed and untreated, but a recent study indicates that OSA can be diagnosed at home just as successfully as at a sleep center. Portable sleep monitors for home testing may make it easier and more convenient for patients to obtain a diagnosis. Both Advanced Brain Monitoring and Sleep Solutions offer home tests to aid in the diagnosis of sleep apnea.
Have you heard of any other interesting sleep apnea therapies in the works? Please share in comments.