Medical Device Daily Associate

If ongoing trials are successful, the device sector may one day have another innovative implantable technology, this one used to treat difficult-to-manage high blood pressure, particularly in patients who have a resistance to hypertension drugs.

CVRx (Minneapolis) reported that it has received FDA approval for a conditional investigational device exemption (IDE) to begin a pivotal clinical to evaluate the safety and effectiveness of its Rheos baroreflex hypertension therapy system, an implantable device to treat high blood pressure.

The blinded study, sponsored by the company, is a prospective, randomized, multi-center trial that will be conducted at up to 40 sites in the U.S. The study seeks to determine the safety and effectiveness of the Rheos System when used in drug-resistant hypertension patients. To be enrolled in the trial, patients need to be resistant to treatment with at least three anti-hypertension agents, including a diuretic. Their systolic blood pressure must be greater than or equal to 160 mmHg.

Data from this clinical trial is intended to support the pre-market approval application for the Rheos system to the FDA.

CVRx’s flagship product, the Rheos system is intended for use in patients who cannot control their blood pressure with medications, or medication combined with lifestyle modifications. The device provides what physicians might describe as a “physiologically rational” method to reduce blood pressure. It is designed to do this with the use of mild electrical signals to influence the body’s blood pressure regulation system, called the baroreflex.

According to Robert Kieval, founder and current vice president and chief technology officer of CVRx, the Rheos is a pacemaker-like device designed to stimulate tissues within the body.

“We stimulate areas of the vascular system that have sensors in them that report blood pressure to the brain,” he told Medical Device Daily. “The brain compares what it believes is the blood pressure to the needs of the body and then makes the appropriate adjustments.”

Kieval said the signals that the device generates are interpreted by the body as a rise in blood pressure that needs to be corrected. The brain then works through the body’s own blood pressure control mechanisms to attempt to restore blood pressure to normal. Thus, in essence, it fools the body and leads to a net reduction in blood pressure.

Kieval likened this mechanism of action to the ability to cool a room by holding a match under a thermostat: “The heat of a match fools the thermostat into thinking that the entire room has become too warm and causes the air conditioning system to be activated.”

The device has thus far enjoyed early clinical success in European and U.S. feasibility clinical trials for its evaluation. European patients started enrolling in the trial in 2004. Early results for the first 12 patients were reported at the European Society of Hypertension meeting in June 2006.

In this study, after three months of active Rheos therapy, systolic blood pressure was reduced by an average of 24 mmHg (189 mmHg vs. 165 mmHg). There were no unanticipated serious adverse events related to the system or procedures.

“The Rheos System represents a fundamentally new approach to therapeutic intervention for resistant hypertension,” said principal investigator, Thomas Pickering, MD, professor of medicine, Columbia University Medical Center – Presbyterian Hospital (New York). “This pivotal study will help us further understand the potential role of this device in treating patients with difficult-to-manage high blood pressure. Reducing high blood pressure can help prevent serious heart and kidney disease, stroke and death.”

The company said initial U.S. results will be presented at the American Heart Association (AHA; Dallas) annual meeting being held in Chicago in November.

Kieval, now chief technology officer, was previously president/CEO of the company but stepped down earlier this month in order to let somebody else lead the company though the clinical trials and ultimately to commercialization. Nadim Yared assumed those titles on Oct. 4.

Yared was most recently the vice president and general manager of Medtronic Navigation , a unit of Medtronic (Minneapolis) that makes integrated image-guided surgery products.

Before joining Medtronic Navigation in 2002, Yared worked with GE Medical (Little Chalfont, UK) for 10 years as an engineer and manager and was eventually promoted to vice president and general manager or GE’s European X-ray business.

Kieval explained that the company grew out of a medical technology incubator called ProtoStar, formed by Piper Jaffray Ventures, NEA and several former executives of Boston Scientific SciMED.

To date, the company has undergone three rounds of financing, he noted: an $8 million round in 2001, a $22 million round in 2003 and a $30 million round this past May, making it one of the biggest venture capital deals of the year for a device company. In all, the company has raised more than $60 million in private funding.

Kieval feels the company’s financing success underscores the importance of the treatment and its market potential.

That potential is enormous since 25% of the 65 million people in the U.S. who have hypertension cannot control their high blood pressure, despite the use of multiple medications.

And hypertension then leads to huge stressors on the individual and the healthcare system as a whole since it is a leading cause of stroke, heart attack, heart failure and kidney disease. It is estimated to cause one in every eight deaths worldwide.