Yale Study of Medtronic's Infuse Spinal Fusion Product Neither Vindicates Nor VillifiesYale Study of Medtronic's Infuse Spinal Fusion Product Neither Vindicates Nor Villifies

Yale released its independent report of Medtronic's controversial bone growth product Infuse after the markets closed on Monday and the results are mixed for the product. As a result, one analyst concludes that Infuse will likely not be pulled from the market.

The evaluation found that the biologics product is as good as but not better than traditional iliac crest bone graft (ICBG) procedures. Further, cancer rates were higher among patients who underwent Medtronic's Infuse procedure. Still, the studies that were commissioned by Medtronic said that the data regarding cancer risk is limited, according to a research note published by RBC Capital Markets senior analyst Glenn Novarro. 

Novarro added that the first study conducted by the University of York found that the data "showed increased fusion rates at 24 months, no clinically significant reduction in pain, and increased cancer incidence of Infuse versus ICBG" even though they could not reach a hard conclusion whether Infuse actually increases the risk of cancer.

Notably the study authors also found that there was no increased risk when patients used Medtronic's Amplify, a more concentrated bone growth product than Infuse, Novarro said.

A second study conducted by Oregon University found that Infuse has no real clinical superiority over traditional procedures whether it is overall success or fusion rates. Notably, the study authors found that "early journal publications misrepresented the effectiveness through selective reporting, duplicate publication, and underreporting" Novarro said. That appeared to echo some of the charges against Medtronic and clinical investigators of the product.

Like the University of York study authors, they found an increased risk for cancer through 24 months following the procedure but could not draw a firm conclusion regarding cancer risk, Novarro said.

Given these studies, Novarro concludes that the decline in sales of Infuse will continue but at a slower rate.

"We believe, on the margin, some doctors may cut back their Infuse usage because of the Oregon State study. However, we believe the headline takeaway from both studies was largely neutral and expect year-to-year declines to moderate," Novarro wrote.

Meanwhile Medtronic must be relieved that the studies did not expose any damning results.

"We are pleased to have reached a milestone in completing this review as we move forward with this important treatment option," said Chris O'Connell, executive vice president and president of Medtronic's Restorative Therapies Group, including the Spine business. "We remain committed to INFUSE Bone Graft, which has a decade of clinical use and has been cited as one of the most important innovations in orthopedic medicine."

 -- By Arundhati Parmar, Senior Editor, MD+DI