Medtronic commits to renal denervation as company details disappointing trial results

Medtronic's Symplicity--Courtesy of Medtronic

Medtronic ($MDT) pledged to plow ahead at some point with a new Symplicity renal denervation trial, even as details of the company's failed U.S. pivotal study released March 29 revealed that the treatment for drug-resistant hypertension worked no better than a sham procedure.

"We will commit to doing another trial in collaboration with the FDA as long as all of the signals we are looking at continue to be positive," Nina Goodheart, general manager of Medtronic's renal denervation group, told Bloomberg in an interview at the American College of Cardiology meeting in Washington, DC. "I'm not saying we will start a U.S. trial tomorrow. It takes time to get it going and we want to understand what happened with this trial."

Goodheart noted in the Bloomberg story that Medtronic will work with the FDA on future renal denervation studies, based on the recommendation of independent advisers in the wake of the company's big setback in its 535-patient Symplicity HTN-3 U.S. pivotal trial. 

Her cautious optimism follows the company's presentation of details from that trial at the ACC meeting, plus publication of the sobering results in The New England Journal of Medicine. An accompanying editorial in NEJM, as Reuters noted, said that the Symplicity HTN-3 trial "brings the renal-denervation train to a grinding halt." The editorial, written by experts from Mount Sinai Roosevelt Hospital/Icahn School of Medicine and New York University School of Medicine, noted that a decrease in systolic blood pressure took place in both the renal-denervation group and the control group. That finding contrasted with earlier results in other trials that showed more promise for renal denervation.

But as the NEJM editorial explained, two previous Medtronic trials didn't rely on a sham-control cohort, so a placebo effect may explain why both groups saw some improvements in the latest trial. The renal denervation group saw blood pressure drop 14 points and the sham procedure group experienced an 11-point dip, Bloomberg noted. While the renal denervation generated slightly better results, the trial researchers said the numbers weren't significantly better than the sham procedure.

Medtronic's Symplicity has approval in other countries outside of the U.S., and the company has said it will continue to market it as it works with FDA officials to figure out how to proceed to U.S. regulatory approval.

Lead investigator Dr. Deepak Bhatt of Brigham and Women's Hospital in Boston told Reuters that researchers will continue to follow patients in the trial for up to 5 years to see if renal denervation shows some sort of delayed benefit.

St. Jude Medical ($STJ) has said it would move forward with its related renal denervation program. Boston Scientific ($BSX) paused its own efforts until more details came out regarding Medtronic's setback, but expressed optimism about advancing its own renal denervation efforts.

- read the Bloomberg story
- here's Reuters' take
- check out the NEJM editorial
- here's the study abstract