Is Renal Denervation Making a Comeback?

4 min


Hypertension - more commonly known as high blood pressure - affects 1.2 billion people worldwide, a figure which has doubled in the last five years alone. It is responsible for 54% of strokes and 47% of cases of ischemic heart disease, killing approximately 7.6 million people every year. It is estimated that of this population, one third do not respond to medication; this is known as resistant hypertension. With no effective method of treatment available for these patients, the race to find a long lasting solution has gained a newfound urgency in recent years.

In 2012 Renal Denervation (RDN) was set to become that miracle treatment. The stakes were huge; cardiovascular companies were making enormous investments and the buzz surrounding this new therapy made major news within the field. But after Medtronic’s unsuccessful clinical trial, the idea was dropped as quickly as it was taken up.

Now, several years on, Renal Denervation is remerging and investments are – once again – being made. But will it prove more effective this time around? What has changed? Or is it fated to be just as disappointing as once before?

A Failed First Trial

Renal Denervation is, in brief, the deliberate damaging of the sympathetic nerve which plays a role in high blood pressure. The procedure is done with an ablation catheter that is inserted through the femoral artery. In 2013, companies likes Medtronic, Covidien, St Jude and Boston were all investing in RDN. The therapy became a major buzz word in the Cardiovascular space, the American College of Cardiology even listing in its ‘top cardiovascular stories to watch for in 2014’.

Medtronic’s 2014 clinical trial, ‘SYMPLICITY HTN-3’, was the largest study on RDN treatment and set to lead the way for the whole industry. However, despite such high expectations, the trial’s results were a major disappointment, failing to show a sustained reduction in blood pressure after six months. Whilst many showed some reduction in blood pressure, it was not enough that patients could stop using medication. What’s more, the control group demonstrated a reduction in blood pressure too, making the results inconclusive. It seemed Renal Denervation didn’t work.

Medtronic’s results forced the entire cardiovascular industry to revaluate the treatment; they took a $200 million write-down on RDN assets and suspended their enrolment in other global SYMPLICITY trials. The industry’s major players followed suit, scaling back or cancelling their RDN programmes and many small companies withdrew their investments altogether.

Learning From SYMPLICITY HTN-3

Since that time, several factors have been identified which can be tied to SYMPLICITY HTN-3’s failure. As more investigation has gone into the trial, evidence has emerged that the trial itself was not conducted well enough to prove RDN is ineffective. With significant drops in blood pressure observed from surgical denervation as early as the 1920s, this innovation still remains the most promising solution for drug-resistant hypertension. Conversation around RDN and its potential has therefore reopened and, with trials proving more conclusive, Medtronic have funded further clinical testing of their own.

The Trial Revised: Spyral HTN Off-Med’s Exciting Results

Medtronic’s revised trial, ‘Spyral HTN-Off Med’, examined RDN without high blood pressure medication, a notable change from the first trial in which patients were taking an average of about five antihypertensive drugs.

What’s more, the more recent trial excluded patients with isolated systolic hypertension – the samples used in SYMPLICITY HTN-3 included patients with this variation, which has been shown to be less responsive to RDN. Spyral HTN also adopted a more aggressive treatment approach to ensure full/significant ablation, using a multi-electrode, spiral catheter that caused circumferential ablation and targeted both the main renal arteries and the branches.

The revised trial resulted in a significant decline in 24-hour systolic and diastolic pressure versus those who underwent the sham procedure, who showed no changes: Spyral HTN was a success. Results suggest that a more intensive approach to ablating renal nerves can reduce blood pressure in patients with untreated mild-to-moderate hypertension and also, in their efficacy, warrant larger, more definitive trials once again.

The Future of RDN

In its more recent trials, Renal Denervation has lowered blood pressure in 75% of patients. Given the prevalence of hypertension and the side effects of antihypertensive medications, it’s likely that funding into RDN and its trialling will continue to increase, pushing the therapy into mainstream medicine very soon. GlobalData believes that RDN will make a full comeback, and that there is the potential for RDN devices to be released in 15 major markets worldwide – including the US, Germany and France – before 2022.

The Need For Specialists

It’s clear from its revival that RDN holds huge potential for the industry. The treatment will not only benefit patients individually, but will also have positive societal implications, as high blood pressure contributes more than $500 billion in direct costs to healthcare systems globally. RDN devices will be able to treat patients with serious resistant hypertension and those with less severe hypertension who are looking for an alternative treatment that will allow them to stop taking medication altogether.

With this said, the need for companies to be investing in talented personnel to drive new technologies is becoming more pressing. CSG has worked with many innovative cardiovascular businesses over the years as they commercialise new therapies and build up international teams. I have a wealth of experience recruiting into this sector, partnering with start-ups as well as Top 20 Global Medical Devices businesses to create new international business units. CSG has set up new divisions in specialist fields such as TAVI, AAA and EP, hiring from EMEA VP level through to local country teams. If you would like support in hiring the best talent for niche therapeutic areas, please don’t hesitate to get in touch at



GlobalData Healthcare, Renal denervation: a fallen innovation that will rise again, 22.11.17

tctmd, Renal Denervation: Proof-of-Concept Study Gives Fresh Jolt to Fizzled Field, 28.8.17

Vascular News, From SYMPLICITY HTN-1 to SPYRAL HTN-OFF MED: The story of renal denervation, 27.9.17

Cardio Brief, Renal Denervation: Back From The Dead Or Deja Vu All Over Again?, 14.8.27

Mass Device, Medtronic readies pivotal trial in renal denervation, 28.8.17