VIVUS, Inc. (Nasdaq: VVUS) today announced that data from a previously reported phase 2 study evaluating the safety and efficacy of the investigational drug Qnexa® for the treatment of obstructive sleep apnea (OSA) were presented at SLEEP 2010, the 24th Annual Meeting of the Associated Professional Sleep Societies (APSS). Data from the study entitled, "A Randomized, Double-Blind, Placebo-Controlled, Parallel-Group Study of Phentermine/Topiramate CR (VI-0521) for the Treatment of Obstructive Sleep Apnea/Hypopnea Syndrome in Obese Adults," were presented by David Winslow, MD, president, Kentucky Research Group, Chest Medicine Associates, P.S.C., Louisville and the study's principal investigator. The presentation marks the first time these results have been presented at a major medical meeting.
The study demonstrated statistically significant improvement in the apnea/hypopnea index (AHI), a measure of the severity of sleep apnea, in patients with OSA treated with Qnexa for 28 weeks. Qnexa-treated patients also experienced significant weight loss, reductions in both systolic and diastolic blood pressure, and reductions in respiratory disturbances and improvements in overnight blood oxygen levels. Qnexa treatment was well-tolerated. The most common side effects were dry mouth, altered taste and sinus infection.
"Obstructive sleep apnea is a serious condition associated with potentially deadly cardiovascular and metabolic events for the more than 18 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. "These positive Qnexa data, from what is considered a sizable study for OSA, are exciting for those of us in the medical community treating obese patients with hypopnea syndrome. Particularly notable are the positive improvements achieved in mean oxygen saturation levels, which are difficult to accomplish and incredibly important. Patients would truly benefit from a safe and effective oral pharmacologic therapy for OSA, and I look forward to further exploring the potential of Qnexa."
OSA is a sleep-related breathing disorder that involves a decrease or complete cessation of airflow despite an ongoing effort to breathe. OSA is associated with an increased risk of hypertension, diabetes, stroke, sudden cardiac death and all-cause mortality. Sleep apnea is one of the leading co-morbidities associated with obesity, and research has shown that weight loss can improve OSA.
The phase 2 study (OB-204) was a single-center, randomized, double-blind, placebo-controlled parallel group trial including 45 obese men and women (BMI 30 to 40 kg/m^2, inclusive), 30 to 65 years of age. Patients enrolled were diagnosed with OSA based on an AHI ≥15 (moderate to severe) at baseline. In addition to receiving active or placebo drug, all patients were provided with a lifestyle modification program.
Highlights of the study include:
- Patients treated with Qnexa for 28 weeks had a nearly two-fold improvement in mean AHI compared with placebo
- Qnexa treatment reduced the number of apnea/hypopnea events from a mean of 45.5 events per hour of sleep to 14.0 - compared to placebo patients with a reduction from a mean 43.5 events per hour of sleep to 27.0 (LS Mean, ITT-LOCF>
- Qnexa treated patients lost 10.3% body weight, or 23.7 lbs, in 28 weeks, compared to 4.2% for placebo patients, or 10.4 lbs (LS Mean ITT-LOCF p<0.001 active vs. placebo).
- Systolic blood pressure was reduced by 15 mm Hg in the Qnexa group from a mean of 138 mm Hg at baseline (LS Mean ITT-LOCF>
- Diastolic blood pressure was reduced by 6.3 mm Hg in the Qnexa group from a mean of 87 mm Hg at baseline (LS Mean ITT-LOCF>
- Mean overnight oxygen saturation was significantly improved in Qnexa patients>
- Qnexa patients had a net reduction in the sleep arousals per hour of 19.5 versus an increase in sleep arousals of 21.2 for the placebo group.
- Qnexa patients also had improvement in sleep quality as measured by a reduction in the Pittsburgh Sleep Quality Index (PSQI) as compared to the placebo group>
- Overall study completion rate was 88.9%.
- Qnexa treatment was well-tolerated with no serious adverse events reported in the Qnexa arm. The most common treatment-emergent adverse events were dry mouth, altered taste, sinusitis, upper respiratory infections, nasopharyngitis, paresthesia, diarrhea and constipation. Most of these adverse events were mild or moderate in severity.
"A safe and effective treatment for obstructive sleep apnea would be valuable for the sleep physician community and for the millions of patients living with this dangerous and often undiagnosed disorder," stated Leland Wilson, chief executive officer of VIVUS. "These phase 2 data indicate that the substantial weight loss achieved with Qnexa can significantly improve sleep apnea as measured by the apnea/hypopnea index. Patients in the study had improvements in multiple secondary endpoints including improvements in their sleep quality. We are pleased that Dr. Winslow is sharing these exciting data with the sleep community at SLEEP 2010, and we look forward to working with the FDA to determine a regulatory path forward for this indication."