
Medical device heavyweight Medtronic (NYSE:MDT) notched some significant milestones in the ongoing clinical studies of the CoreValve transcatheter aortic valve implantation systems.
Medtronic announced this week that it had closed enrollment in the "high risk" arm of its U.S. pivotal trial and that the FDA granted the company approval to expand a separate CoreValve study to lower risk patients.
Medtronic hit its cap for the CoreValveR U.S. pivotal trial, having enrolled more than 1,500 patients with severe aortic stenosis who are at high or extreme risk for open-heart aortic valve surgery, according to a press release.
The company plans to continue enrolling patients in its "extreme risk" arm, which it received permission to do under an FDA Continued Access Policy after enrollment for that group reached its cap in January.
The Continued Access Policy products with investigational device exemption status to continue clinical trial enrollment above initially approved numbers under the criteria that they either meet a public health need or demonstrate no significant safety concerns and prove effective with preliminary evidence, according to the FDA’s website.
Medtronic hopes to expand its CAP approval to enroll more patients in the high risk arm as well.
In addition, Medtronic can now expand its TAVI research to evaluate CoreValve in lower risk patients, according to the company statement.
The device maker will enroll those patients in its ongoing Surgical Replacement & Transcatheter Aortic Valve Implantation study, which Medtronic says is the largest global, randomized, controlled TAVI trial to date.
That study will evaluate around 2,500 lower-risk heart failure patients. The FDA granted Medtronic conditional approval to assess CoreValve in "intermediate risk" aortic stenosis patients, with U.S. enrollment slated to begin within weeks.
Researchers are evaluating 3 different sizes of the CoreValve device: 26mm, 29mm and 31mm. The study also considers 3 different access routes: Through the transfemoral artery in the upper leg, via the subclavian artery beneath the collar bone and directly through the aorta via a minimally invasive surgical incision.
High risk patients are being being randomized to receive either the CoreValve aortic valve replacement or open-heart surgery, while "extreme risk" patients are being compared to a performance goal derived from other studies."
CoreValve was the first TAVR system to hit the market when it won CE Mark approval in the European Union in March 2007. Edwards Lifesciences (NYSE:EW) won CE Mark approval for its Sapien TAVR system in September of that year and landed FDA clearance for its Sapien system in Nov. 2011.
Medtronic has predicted that CoreValve will be "a 2014 product" for the U.S.