Senators asking Medtronic to address concerns over bone graft product

Two U.S. senators have asked Medtronic to address concerns about the safety of its InFuse bone graft product, as well as financial ties between the company and clinical investigators who reviewed the device.

Sen. Chuck Grassley, R-Iowa, is one of the senators who sent a letter to Medtronic this week, asking for detailed information about InFuse.

"It's kind of alarming to learn that there's conflicting conclusions about the device's safety and the complications that can result from it," Grassley said. "Then there's the lack of disclosure of payments to certain consultants. It raises questions about the competence of the people doing the work."

Medtronic said it will respond, but also said the "adverse events" the senators cite are disclosed on government-approved product labels. Medtronic also said financial relationships with researchers don't affect its reports to the FDA.

Sales of InFuse suffered after regulators warned the product has been linked to some life-threatening complications.

The InFuse bone graft product is approved to treat, fusion of the lumbar spine, degenerative disc disease and some other conditions.