CDU Associate

For only the second time since its creation, the FDA's Medical Devices Dispute Resolution Panel (MDDRP) will determine the fate of a company’s technology. The five-person panel is scheduled to meet Dec. 15 to review the premarket approval (PMA) application of Acorn Cardiovascular (St. Paul, Minnesota) for its CorCap cardiac support device (CSD), a mesh wrap implanted around the heart to provide ventricular support and to reduce ventricular wall stress in patients with dilated cardiomyopathy and symptomatic heart failure, worsening despite optimal medical management.

The panel serves as final recourse for companies in their bid to win device approval when all other avenues have failed them or if they decide that they don't want to, or need to, do further trials. In July 2005 the FDA’s cardiovascular device panel voted against recommending approval of the CorCap, citing what it saw as gaps in New York Heart Association (NYHA) functional class follow-up data and the lack of substantial evidence of efficacy, compared to control.

Panel members also expressed concern about how a CorCap implant might impact the effectiveness of follow-on surgical procedures, if necessary. That concern pinpointed trial data indicating an 11% chance of major heart surgery two years after CorCap implantation, despite being significantly below the 26% rate of heart surgery for the control group. The FDA then issued a “non-approvable” letter.

Rich Lunsford, Acorn's president/CEO, said that the agency gave the company several options to address the panel's concerns. "One of those options was to conduct a subsequent analysis that would identify where the patients did the best within our subset, which is what we chose," he said.

Though the company presented that data to the FDA this past January, it then in February received a second "non-approvable" letter. The letter did not provide reasons for the decision, Lunsford told Cardiovascular Device Update. “It just said we want you to go out and get additional patients." In essence, it wanted another trial.

The company made the call that another trial was not needed and filed for referral to the MDDRP, that request granted by Les Weinstein, ombudsman for the Center for Devices and Radiological Health, who established the panel and administers it.

Acorn said it decided to take the dispute route based on what it believes is robust trial data. "This is the largest cardiac surgery multicenter trial that's ever been conducted," Lunsford said, with more than 300 patients enrolled at 29 sites in the U.S. and Canada. The CSD group showed improvements in several categories, with more patients improved according to NYHA class (38% vs. 27%) and fewer patients "worsened" (37% vs. 45%). The CSD group had fewer follow-on major cardiac procedures (such as heart transplant, implantation of a ventricular assist device or need for electrical stimulation therapy), compared to the control group. And using a quality-of-life assessment, the CSD group reported greater improvement in quality of life over the control group

Lunsford noted that the company's trial for the device has cost it nearly $30 million since it began in 2000, and he wonders what more the agency needs to grant approval, particularly since he said it wanted the company to use "similar endpoints" for the new trial.

If the MDDRP needs to take a vote, Lunsford said, its recommendation will then be forwarded to the head of the CDRH, Dan Schultz, for final action. While Lunsford noted that Schultz could turn down a positive MDDRP recommendation, he does not see this as a likely scenario.

"If this panel votes to approve the PMA, we're looking at this as highly likely that we'll get an approval."

The CorCap fills a gap in the treatment continuum of heart failure, Lunsford said, and could be most useful for NYHA Class III patients, moderate cases of heart failure patients that are not doing well on medical therapy, a pool that he said ranged from 1 million to 1.5 million of the 5 million U.S. heart failure patients.

He said the company feels that it really has nothing to lose by pursuing the dispute resolution pathway. "Everything in the company is based on the success of this approval, so we felt that the decision was pretty easy.” Lunsford said that doing another trial would cost Acorn another three years and $15 million to $20 million. "We are looking forward to the opportunity to present this data to the dispute panel,” he said.

The dispute panel waters aren’t completely uncharted. One other company, Lifecore Biomedical (Chaska, Minnesota), won a panel appeal for its Intergel Solution for the reduction of adhesions following gynecological surgery in September 2001. (That product was withdrawn in 2003 by the company because of complaints about it, primarily related to off-label use.)

Another company in the cardiovascular device sector also is taking the dispute resolution route. Cardima (Fremont, California) in July said it would go before the panel to seek reverasal of an advisory panel vote against approval of its Refelation Tx micro-catheter system to treat atrial fibrillation. That meeting is set for some time in January.