US-based Medtronic has announced that the Symplicity HTN-3 clinical trial evaluating the use of its renal denervation system in patients with treatment-resistant hypertension has failed to meet its primary efficacy endpoint.
However, the Symplicity HTN-3 clinical trial, however, has met its primary safety endpoint. The trial's data safety monitoring board concluded that there were no safety concerns in the study.
Change in office blood pressure from baseline to six months and incidence of major adverse events were the primary endpoints of the study.
Based on the Symplicity HTN-3 study findings, Medtronic intends to formulate a panel of independent advisors with physicians and researchers who will be asked to make recommendations about the future of the global hypertension clinical trial programme.
Pending panel review of the study, the company intends to suspend patient enrolment in the three countries where renal denervation hypertension trials are being conducted for regulatory approvals (Symplicity HTN-4 in the US, HTN-Japan and HTN-India).
The company also intends to continue the Global Symplicity post-market surveillance registry and renal denervation studies evaluating other non-hypertension indications.
Medtronic chief medical officer Dr Rick Kuntz said the company was disappointed that the clinical trial failed to meet its primary efficacy endpoint.
"We believe this course of action is the most prudent and will help us thoroughly evaluate these findings and determine the appropriate next steps for renal denervation therapy," said Kuntz. "We would like to thank the patients and investigators for their participation in the trial and their important contribution to the field of hypertension research."
Medtronic designed the Symplicity HTN-3 randomised, controlled trial to measure the safety and efficacy of its Symplicity renal denervation system in patients with treatment-resistant hypertension and systolic blood pressure higher than 160mmHg in the US.
The study randomised 535 treatment-resistant hypertension patients in 87 US medical centres. Patients receiving the investigational treatment were compared with a sham-control group that did not receive treatment, with all patients continuing to take their blood pressure medications.
Medtronic's Symplicity renal denervation system features a flexible catheter and proprietary generator.
The system is specifically designed to deliver low-level radio frequency (RF) energy through the wall of the renal artery to achieve renal denervation.
Image: Medtronic's world headquarters in Minneapolis. Photo: courtesy of Medtronic, Inc.