Vivus, Inc. (VVUS) said this Monday morning that a proof-of-concept study published in the journal SLEEP showed that patients with moderate to severe obstructive sleep apnea (OSA) benefited from taking phentermine and topiramate extended-release capsules. The Mountain View, California company markets the capsules currently under the brand name Qsymia after receiving FDA approval in July as a treatment for obesity. The drug has not been approved for OSA.
After 28 weeks of treatment, patients in the study showed significant improvement in key measures of OSA and cardiovascular risk factors along with weight loss, according to the research.
Current standard of care for OSA is positive airway pressure (PAP), a device that keeps the upper airway open through increased air pressure. There are currently no drugs available for OSA, a chronic condition that affects between three and seven percent of the U.S. population. Sufferers of OSA demonstrate abnormal breathing patterns during sleep in which breathing is very shallow (hypopnea) or stops completely (apnea) for at least 10 seconds. Hypertension, cardiovascular disease, heart attacks and stroke are all associated with OSA.
45 obese patients who were not using PAP were randomized to placebo or treatment for evaluation in the study with both groups receiving intensive lifestyle modification counseling. The primary endpoint was change in the apnea-hypopnea index (AHI), a measure of the average number of breathing interruptions per hour during sleep.
At the end of the study the treated cohort showed a reduction in apnea-hypopnea events from 44 events per hour (considered severe) to 14 events per hour (considered mild). Cardiovascular and metabolic risk factors, such as systolic blood pressure and mean overnight oxygen saturation, were also improved. The mean weigh loss for the treated group was -10.3 percent, compared to -4.2 percent in the placebo group.
“Obstructive sleep apnea is a serious condition associated with potentially deadly cardiovascular and metabolic events for the more than 15 million patients living with the disease. Unfortunately, there are no drug treatments available for the condition, and because current treatment options are limited to devices or surgery, patient compliance is low,” stated David Winslow, MD., the principal investigator of the study and lead author of the paper. “These positive data, from what is considered a sizable study for OSA, are exciting for those of us in the medical community treating obese patients with this condition.”
Additional larger-scale studies are necessary to further evaluate the results, but Vivus believes that Qsymia, combined with lifestyle modification holds promise as a new treatment for OSA patients that are unable to use PAP therapy.
Shares of VVUS went through a substantial appreciation leading into the FDA approval earlier this year to hit 52-week highs of $31.21. A poor earnings report, slow initial sales of Qsymia and failure to gain approval of European drug regulators because of concerns over potential side effects have crippled shares in recent months back to the area of $10 each. Shares closed Friday at $10.84, up 5.86 percent during the trading session are rising in early Monday trading on the latest news.