* Reviewers say valve demonstrated superiority in trial
* Risk of stroke may be contentious issue at FDA panel
* If approved, valve would be first of its kind in U.S. (Adds valve-in-valve concerns, analyst comment, trial details, byline)
By Alina Selyukh
WASHINGTON, July 18 (Reuters) - U.S. drug reviewers said Edwards Lifesciences Corp’s (EW.N) heart valve “demonstrated superiority” in a trial that also showed the device’s safety and effectiveness for patients considered to be too sick to have open-heart surgery.
The trial, however, also showed people were at high risk of stroke or other neurological impact after using the valve, and the reviewers, in documents released on Monday, said adverse neurological effects remain an important safety consideration.
A panel of FDA advisers will look at the data on Edwards’ Sapien heart valve on Wednesday, and the reviewers specifically asked the advisory panel to weigh the device’s benefits versus risks.
If approved, the Edwards valve would be the first so-called transcatheter aortic valve sold in the United States. Edwards has sold such a valve in Europe since 2007.
Analysts have pegged the worldwide market for transcatheter aortic valves at more than $2 billion in annual sales.
“In our view, the only contentious issue for the panel will be the neurovascular events because the event rate was 3.1 (times) higher with Sapien,” Wells Fargo Securities analyst Larry Biegelsen said in a note.
“Overall, the FDA briefing documents were in line with our expectations and we continue to expect a favorable panel outcome,” he said.
The Sapien transcatheter heart valve is a replacement valve that spares patients the need for open-heart surgery. It is threaded into place through the arteries via a catheter.
The catheter is inserted either in the femoral artery in the groin or through a small incision between the ribs, avoiding surgery in which the ribs are sawed open, the heart is stopped and a new valve is sewn in.
Sophisticated devices and nonsurgical techniques are taking the spotlight as the wave of the future in the battle against heart disease as drugmakers produce fewer new medicines to fight the world’s leading cause of death. [ID:nN14240333]
Edwards submitted its application to the FDA last fall based on data from the Cohort B portion of its Partner clinical trial for patients with severe aortic stenosis — a narrowing of the valve — who are considered too sick for open-heart surgery.
In Cohort A, Edwards compared its valve with open-heart surgery, while in Cohort B the device was tested against “standard” therapy. The FDA advisory panel is expected to discuss who gets considered “too sick” and how.
Edwards argued that the valve “substantially increases survival compared to the standard of care,” but the FDA reviewers underscored that no clear “standard” therapy exists for such circumstances.
The trial compared Edwards’ heart valve to an array of therapies, and the reviewers asked the advisory panel to consider whether that variedness of therapies impacts the evaluation of the device’s safety and effectiveness.
The trial showed patients using the valve had a 3.1 times higher rate of developing neurological problems such as stroke, intracranial hemorrhage or transient ischemic attacks.
At the same time, one year after the procedure, the survival rate for patients implanted with Edwards’ valve was 69.3 percent, compared with 50.3 percent in those treated with other therapies.
Patients in the Edwards study were not taking blood clot-preventing anticoagulants or thrombus-preventing antiplatelet drugs. Edwards has proposed requiring such medications for its heart valve patients to lower the risk of stroke.
In the documents, FDA reviewers also said they were concerned that the valve’s growing use would lead to more and more operations implanting one valve inside another, which has not been tested. The reviewers asked the advisory panel to consider what labeling, operator training or other testing could address this concern.
“Panel questions raise some concerns, but nothing that would derail approval,” JPMorgan analyst Michael Weinstein said in a note, adding that the chances of a positive vote were “extremely high.” (Reporting by Alina Selyukh; Editing by Derek Caney, Maureen Bavdek and John Wallace)