In an op-ed piece in the Wall Street Journal Scott Gottlieb, a former FDA official under George W. Bush, argues that the FDA should stop requiring medical device companies to use sham procedures when they test certain new products. To support his argument he uses the example of renal denervation, a once highly promising new technology for lowering blood pressure. Unfortunately, Gottlieb extracts exactly the wrong lesson from this story, because the renal denervation story is a perfect example of why sham procedures can be both necessary and more ethical than any alternative.
At first glance it’s hard to disagree with Gottlieb. The idea that patients would receive an invasive surgical procedure that could do no good appears abhorrent. “Research that introduces harm or risk with no opportunity for benefit would seem to conflict with the principles governing research on humans,” writes Gottlieb.
But the same exact words could and should be used to describe medical devices with no proven benefit. In such cases, however, instead of the relatively small number of patients potentially exposed to harm in clinical studies, the number of patients exposed to harm in the real world may be larger by many orders of magnitude.
Let’s examine this issue using the same example used by Gottlieb: renal denervation….
Click here to read the full post on Forbes.
The hypertension community woke up this morning to a large dose of reality with an announcement by Medtronic that the novel SYMPLICITY HTN-3 trial of its much-anticipated renal denervation device had failed to meet its primary efficacy endpoint. Renal denervation has been widely touted as a breakthrough product that could dramatically lower blood pressure by as much as 30 mm Hg, allowing physicians to cure the most severe form of high blood pressure, resistant hypertension.
“SYMPLICITY HTN-3 met its primary safety endpoint related to the incidence of major adverse events one month following randomization and renal artery stenosis to six months,” said Deepak Bhatt, the co-principal investigator of the trial, in the Medtronic press release. “Importantly, however, the trial did not meet its primary efficacy endpoint.”
Click here to read the full post on Forbes.
Early trials of renal denervation, the innovative new catheter-based blood pressure lowering technology, have resulted in extremely impressive drops in systolic blood pressure in the range of 30 mm Hg. These results have sparked a great deal of excitement in the hypertension community and stirred the interest of a multitude of medical device companies. Some experts have proclaimed renal denervation a potential “cure” for resistant hypertension, perhaps enabling a significant number of patients to eliminate all drug therapy. Other expanded uses of the technology in more moderate forms of hypertension and other diseases are under active consideration. Now, however, a new analysis of the available data suggests the troubling possibility that renal denervation may not be nearly as effective in cutting blood pressure as had been suggested in the earlier trials. Rather than reducing systolic blood pressure by 30 mm hg, the new analysis suggests that a more realistic estimate of the effect of renal denervation may be a much more modest reduction of about 11 mm Hg.
A paper published online in Heart demonstrates that the large reductions in blood pressure seen so far in clinical trials of renal denervation may be a consequence of certain key aspects in the design of these trials. The apparent blood pressure lowering effect of renal denervation has been greatly magnified because the trials have been uncontrolled, unblinded, and have utilized office-based blood pressure measurements rather than the far more reliable and consistent ambulatory blood pressure monitoring (ABPM).
Click here to read the full story on Forbes.
The already hot field of renal denervation for resistant hypertension just got a little hotter. With the announcement of a clinical trial powered to detect improvements in cardiovascular outcomes, St. Jude Medical has raised the stakes.
“To date, the renal denervation studies that have been conducted only looked at reducing blood pressure in patients with uncontrolled or resistant hypertension,” said Michael Böhm, a principal investigator for the trial, in a St. Jude press release. “What we need to know is if this minimally invasive approach for treating hypertension also correlates to a reduction in major cardiac events such as heart attack, stroke and death, which are the primary risks for patients whose blood pressure is not well controlled.”
Click here to read the entire post on Forbes.
St Jude EngligHTN Rendal Denervation System
Over on CardioExchange, Murray Essler, the chief investigator of the Symplicity HTN-2 trial, answers questions from John Ryan about renal denervation:
Non-pharmacologic antihypertensive measures must remain the starting point for patients with hypertension, but will often not be enough. Renal denervation should be reserved for patients in whom behavior modification combined with adequate and skillful antihypertensive drug prescribing cannot achieve BP reduction to target. There are no clinical trial data to support renal denervation in hypertension outside of this setting. In countries where the “genie is out of the bottle”, and clinical use is authorized, prevention of overuse will be difficult. In some instances government regulations will confine the use of renal denervation to drug-resistant hypertension. Insurer or governmental reimbursement rules should be framed to prevent overuse.
Click here to read the entire CardioExchange interview.