Symplicity HTN-2 trial shows significant blood pressure reduction, with no evidence of renal impairment, at six months post treatment


Six month pooled outcomes from randomised and crossover patients in the Symplicity HTN-2 clinical trial following renal denervation with the Symplicity renal denervation system (Medtronic) showed significant, sustained blood pressure reduction in patients with treatment-resistant hypertension.

Data presented on 27 April at the 22nd annual scientific meeting of the European Society of Hypertension showed patients (n=84) who received renal denervation treatment with Symplicity experienced a mean blood pressure reduction of -28/-10 mm Hg (p<0.001) at six months following treatment compared with baseline. No evidence of renal impairment was observed and renal function measures remained unchanged.

This pooled analysis included change in blood pressure at six months for all patients randomised to receive renal denervation with Symplicity at baseline (n=49), as well as patients in the control group (n=35) who met entry criteria and crossed over to the treatment group following assessment of the initial six month primary endpoint.

“The Symplicity clinical programme is the longest and largest clinical programme of its kind evaluating renal denervation in resistant hypertension,” said Markus Schlaich, associate professor, head, Hypertension & Kidney Disease, Baker IDI Heart and Diabetes Institute in Melbourne, Australia.

“This largest pooled analysis of controlled trial data at six months adds to the growing body of clinical evidence about the safety, effectiveness and sustainability of blood pressure reductions achieved with renal denervation.”

Six-month pooled outcome data from the Symplicity HTN-2 study

The Symplicity HTN-2 trial is an international, multicentre, prospective, randomised, controlled study of the safety and effectiveness of renal denervation in patients with treatment-resistant hypertension. One hundred and six patients were enrolled from 24 investigational sites. At baseline, the randomised treatment and control patients had similar high blood pressures: 178/97 mm Hg and 178/98 mm Hg, respectively, despite both receiving an average daily regimen of five antihypertensive medications. Patients in the control arm of the study were offered renal denervation following assessment of the trial’s primary endpoint at six months following randomisation. Pre-randomisation, all patients in the study had an office-based systolic blood pressure ≥160 mm Hg despite adherence to at least three antihypertensive medications given at optimal dosage. Mean change in systolic and diastolic blood pressure was -28/-10 mg Hg (n=84) from baseline (p<0.001) to six months post-treatment. Renal function measures were unchanged (eGFR: 82.1±20.2 vs. 80.5±18.9mL/min/1.73m2; p=NS). There was one right artery dissection in a crossover patient, which occurred while injecting contrast during angiography. No other serious procedure-related adverse events occurred.

The FDA granted Medtronic approval for the protocol for SYMPLICITY HTN-3, the company’s US clinical trial of the Symplicity renal denervation system for treatment resistant hypertension in August 2011. SYMPLICITY HTN-3 is a randomised controlled trial designed to evaluate the safety and effectiveness of renal denervation with the Symplicity renal denervation system in patients with treatment-resistant hypertension. The study will include approximately 530 treatment-resistant hypertension patients across up to 90 US medical centres.