One Year Symplicity™ HTN-2 Trial Results Show Sustained BP Reduction

In short

It’s all good news for renal denervation therapy as Medtronic, Inc. suggests we take a look at the one-year results from its Symplicity™ HTN-2, renal denervation trial. The data, published online before print in Circulation, the Journal of the American Heart Association, showed patients who initially received treatment with the Symplicity™ renal denervation system sustained a significant drop in blood pressure compared to baseline at 12 months, demonstrating preservation of the benefit at six month follow-up.

Background

In case you’ve missed it, renal denervation therapy is a minimally invasive, catheter-based procedure that modulates the output of nerves that lie within the renal artery wall and lead into and out of the kidneys. The nerves passing to the kidneys are part of the sympathetic nervous system, which affects the major organs that are responsible for regulating blood pressure: the brain, the heart, the kidneys and the blood vessels.

Symplicity HTN-2 is an international, multi-centre, prospective, randomised, controlled study of renal denervation in patients with treatment-resistant hypertension, involving use of Medtronic’s Symplicity renal dnervation system. One hundred and six patients were randomly allocated in a one-to-one ratio to undergo renal denervation with previous anti-hypertensive medication treatment or to maintain previous anti-hypertensive medication treatment alone (control group) at 24 participating centers. Patients in the control arm of the study were offered renal denervation following assessment of the trial’s primary endpoint at six months following randomization.

In the study, 47 patients sustained a significant drop in blood pressure (-28/-10 mm Hg [p<0.001]) compared to baseline at 12 months; these 12 month results demonstrate preservation of the benefit noted at six month follow-up (-32/-12 mm Hg).  Furthermore no device-related serious adverse events, no late vascular complications, and no significant decline in kidney function were reported at 12 months.  No device-related serious adverse events, no late vascular complications, and no significant decline in kidney function were reported at 12 months.

Also reported in the manuscript were 6 month results of 35 patients in the control group who received renal denervation after the primary endpoint was assessed at six months post randomisation (referred to as the crossover group). The crossover group also showed a significant drop in blood pressure six months after the renal denervation procedure (-24/-8 mm Hg [p<0.001]). This decrease in blood pressure is similar to the blood pressure reduction in the initial treatment arm at 6 months.

Investigator comments

“We continue to see positive results from the Symplicity HTN-2 clinical trial, demonstrating consistent, long-term blood pressure reduction with the Symplicity system in patients with treatment-resistant hypertension, who have a three-fold increase in risk of cardiovascular events,” said Murray Esler, M.B.B.S., Ph.D., principal investigator of the Symplicity HTN-2 trial and Senior Director of the Baker IDI Heart and Diabetes Institute of Melbourne, Australia. “These data further substantiate the clinical benefits of renal denervation with Symplicity over longer periods of time in this difficult-to-treat patient group.”

Regulatory status

The Symplicity renal denervation system is not approved by the U.S. Food and Drug Administration (FDA) for commercial distribution in the United States.

Source: Medtronic, Inc.