CVRx, a Minneapolis-based developer of an implantable device for the control of high blood pressure, raised $65 million in a fourth round of funding that will support a “pivotal” clinical trial of the device. The round was led by Johnson & Johnson Development, and also included existing investors New Enterprise Associates, Thomas Weisel Healthcare Venture Partners, InterWest Partners, ABS Ventures, Frazier Healthcare Ventures and SightLine Partners. CVRx has so far raised a total of $125 million.

The company’s Rheos Baroreflex device is designed to stimulate the body’s own blood-pressure regulation system — known as the baroreflex — to control hypertension. It consists of an implantable pulse generator and two lead wires that are attached to the left and right carotid arteries. Using timed electrical stimulation, the device triggers the baroreflex, which in turn signals the brain to lower blood pressure throughout the body. This sort of “neuromodulation” approach is an increasingly hot area in medical-device development, although it remains largely unproven.