
Medtronic (NYSE:MDT) said it’s completed enrollment in the "extreme risk" arm of a pivotal trial for the CoreValve device and won FDA approval to add more subjects to the cohort.
The federal watchdog agency granted a Continued Access Study protocol that will allow Medtronic to continue enrolling "extreme risk" patients in the trial. It’s slated to include more than 1,500 patients across 45 U.S. sites who are deemed either "high risk" or "extreme risk" for surgical heart valve replacement, with about ⅔ of patients in the "high risk" arm.
"Medtronic is very pleased with our investigators’ enrollment progress and with the clinical community’s enthusiasm for the CoreValve U.S. trial," senior VP and structural heart president Dr. John Liddicoat said in prepared remarks.
The device is a transcatheter aortic valve implantation system, designed as a minimally invasive treatment for patients with severe heart disease who are unable to undergo open-heart surgery.
"High risk" patients are being randomized to receive either the CoreValve system or surgery, while "extreme risk" patients are being compared to a performance goal derived from other studies, according to a press release.
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.
The Minneapolis, Minn.-based med-tech giant expects enrollment of "high risk" patients to close later this year, according to the release.
The FDA nod for more "extreme risk" patients was made under the agency’s Continued Access Policy, which allows clinical trials for products with investigational device exemption status to continue enrollment 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.
The news has yet to resonate strongly with The Street, where MDT shares remained flat at $39.35 as of 3:30 p.m. today.
CoreValve was the first TAVR system to hit the market when it won CE Mark approval in the European Union in March 2007, Medtronic spokeswoman Kathleen Janasz told MassDevice.
Edwards Lifesciences Inc. (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.
Janasz confirmed that Medtronic anticipates a CoreValve launch in the U.S. in 2014, as it said at the European Society of Cardiology Congress in Aug. 2011.
CoreValve has undergone first implants in Thailand, Singapore, China, Hong Kong and Taiwan since Sept. 2010, she told us.
TAVR technology is at the heart of an ongoing patent lawsuit between Medtronic and Edwards.

Edwards Lifesciences’ Sapien
Edwards and CoreValve Inc. began the spat when the Irvine, Calif.-based rivals filed suit against each other in 2007. Medtronic inherited the beef when it purchased CoreValve for $1 billion in 2009.
Edwards claimed $73.5 million win in April 2010, but in February of last year Judge Gregory Sleet of the U.S. District Court for Delaware rejected an Edwards motion to enjoin Medtronic from making and selling the aortic valve replacement device. Edwards promised to appeal the unfavorable rulings.
More recently, Medtronic appealed Edwards’ patent win earlier this month, arguing that CoreValve does not infringe due to on exact wording in the patent.