AT CHEST 2017
TORONTO (FRONTLINE MEDICAL NEWS) – The implanted phrenic-nerve stimulation device that received Food and Drug Administration marketing approval in October 2017 for treating central sleep apnea has now shown safety and efficacy out to 18 months of continuous use in 102 patients.
After 18 months of treatment with the remede System, patients’ outcomes remained stable and patients continued to see the improvements they had experienced after 6 and 12 months of treatment. These improvements included significant average reductions from baseline in apnea-hypopnea index and central apnea index and significant increases in oxygenation and sleep quality, Andrew C. Kao, MD, said at the CHEST annual meeting.
“We were concerned that there would be a degradation of the benefit [over time]. We are very happy that the benefit was sustained,” said Dr. Kao, a heart failure cardiologist at Saint Luke’s Health System in Kansas City, Mo.
Dr. Kao did not report an 18-month follow-up for the study’s primary endpoint, the percentage of patients after 6 months on treatment who had at least a 50% reduction from baseline in their apnea-hypopnea index. His report focused on the 6-, 12-, and 18-month changes relative to baseline for five secondary outcomes: central sleep apnea index, apnea-hypopnea index, arousal index, oxygen desaturation index, and time spent in REM sleep. For all five of these outcomes, the 102 patients showed an average, statistically significant improvement compared with baseline after 6 months on treatment that persisted virtually unchanged at 12 and 18 months.
For example, average central sleep apnea index fell from 27 events/hour at baseline to 5 per hour at 6, 12, and 18 months. Average apnea-hypopnea index fell from 46 events/hour at baseline to about 25 per hour at 6, 12, and 18 months. The average percentage of sleep spent in REM sleep improved from 12% at baseline to about 15% at 6, 12, and 18 months.
During 18 months of treatment following device implantation, four of the 102 patients had a serious adverse event. One patient required lead repositioning to relieve discomfort and three had an interaction with an implanted cardiac device. The effects resolved in all four patients without long-term impact. An additional 16 patients had discomfort that required an unscheduled medical visit, but these were not classified as serious episodes, and in 14 of these patients the discomfort resolved.
The remede System phrenic-nerve stimulator received FDA marketing approval for moderate to severe central sleep apnea based on 6-month efficacy and 12-month safety data (Lancet. 2016 Sept 3;388:974-82). The Pivotal Trial of the remede System enrolled 151 patients with an apnea-hypopnea index of at least 20 events/hour, about half of whom had heart failure. All patients received a device implant: In the initial intervention group of 73 patients, researchers turned on the device 1 month after implantation, and in the 78 patients randomized to the initial control arm, the device remained off for the first 7 months and then went active. The researchers followed up with 46 patients drawn from both the original treatment arm and 56 patients from the original control arm, at which point the patients had been receiving 18 months of treatment.
The remede System pivotal trial was sponsored by Respicardia, which markets the phrenic-verse stimulator. Dr. Kao’s institution, Saint Luke’s Health System, received grant support from Respicardia.
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