Background
Catheter-based renal denervation has significantly reduced blood pressure in previous
studies. Following a positive pilot trial, the SPYRAL HTN-OFF MED (SPYRAL Pivotal)
trial was designed to assess the efficacy of renal denervation in the absence of antihypertensive
medications.
Methods
44 study sites in Australia, Austria, Canada, Germany, Greece, Ireland, Japan, the
UK, and the USA, hypertensive patients with office systolic blood pressure of 150
mm Hg to less than 180 mm Hg were randomly assigned 1:1 to either a renal denervation
or sham procedure. The primary efficacy endpoint was baseline-adjusted change in 24-h
systolic blood pressure and the secondary efficacy endpoint was baseline-adjusted
change in office systolic blood pressure from baseline to 3 months after the procedure.
We used a Bayesian design with an informative prior, so the primary analysis combines
evidence from the pilot and Pivotal trials. The primary efficacy and safety analyses
were done in the intention-to-treat population. This trial is registered at
ClinicalTrials.gov,
NCT02439749.
Findings
From June 25, 2015, to Oct 15, 2019, 331 patients were randomly assigned to either
renal denervation (n=166) or a sham procedure (n=165). The primary and secondary efficacy
endpoints were met, with posterior probability of superiority more than 0·999 for
both. The treatment difference between the two groups for 24-h systolic blood pressure
was −3·9 mm Hg (Bayesian 95% credible interval −6·2 to −1·6) and for office systolic
blood pressure the difference was −6·5 mm Hg (−9·6 to −3·5). No major device-related
or procedural-related safety events occurred up to 3 months.
Interpretation
SPYRAL Pivotal showed the superiority of catheter-based renal denervation compared
with a sham procedure to safely lower blood pressure in the absence of antihypertensive
medications.
Funding
Medtronic.
