Back in January 2014, Fridley, Minn.-based Medtronic shocked medtech when it announced that the highly anticipated Symplicity HTN-3 trial, examining ablation of the nerves around the renal arteries in treating hypertension, failed to meet its efficacy endpoint. The company suspended enrollment in its other Symplicity trials and later took a $200 million write-down on its renal denervation assets. News of the trial’s failure reverberated throughout the medical device industry, prompting other companies to follow suit by either scaling back their RDN programs or spiking them altogether.
Last summer Medtronic said positive preliminary results from another study, the 353-patient Spyral HTN-Off Med investigational device exemption trial, prompted it to proceed with its plans to win regulatory approvals for the Symplicity Spyral ablation catheter in the U.S., Japan and elsewhere. Spyral HTN-Off Med study is one of a pair designed to examine RDN with and without high blood pressure medication. Unlike the Symplicity-3 trial and its cohort of severe, treatment-resistant high blood pressure, each 100-patient trial was slated to enroll subjects with moderate- to high-risk hypertension. Spyral On-Med is designed to evaluate the treatment with the use of anti-hypertensive medications, but not at the maximum doses required by Symplicity-3’s protocol.
The new 433-patient Spyral HTN pivotal trial will compare renal denervation with a sham procedure in hypertension patients who are not on medication for the condition, with a primary efficacy endpoint of 24-hour blood pressure measurement at three months and a primary safety endpoint of the rate of major adverse events at one month, Medtronic said.
“This global pivotal trial demonstrates our commitment to realizing the full potential of renal denervation and will support therapy approval and adoption in new geographies,” coronary & renal denervation general manager Dave Moeller said in prepared remarks. “Initiation of the pivotal trial represents another important step in establishing the clinical utility of renal denervation for hypertension and we are confident we have the trial and technology to propel the therapy forward.”
“We are entering a new era for blood pressure control with data from a rigorous sham controlled trial showing that renal denervation significantly lowered blood pressure in the absence of antihypertension medications,” added co-principal investigator Dr. David Kandzari of Atlanta’s Piedmont Heart Institute.
“We understand the renal denervation procedure much better than we did just a few years ago, and our growing body of clinical evidence strongly suggests that this unique procedure can positively impact patients with high blood pressure,” co-principal investigator Dr. Raymond Townsend, of the Hospital of the University of Pennsylvania, said in the statement.