UPDATED: Medtronic shut down study of Infuse bone graft and tucked away the evidence: Report

Infuse Bone Graft/LT-Cage Lumbar Tapered Fusion Device

Medtronic ($MDT) is coming under fire for shutting down a study of its bone graft, Infuse, and allegedly tucking away the data. A recent report from The Minneapolis Star Tribune said that the company uncovered serious problems linked to the product but didn't immediately tell anyone, which sparked pushback from the government and the public.

Back in 2008, the company pulled the plug on a retrospective chart review (RCR) of Infuse. The study looked at the medical records of 3,647 patients at 26 sites who had gotten the graft, and was meant to garner more data to prep Infuse for new uses. While some of the records included good outcomes, others showed more than 1,000 complications, some of which were linked to Infuse. Other records turned up four deaths from causes such as heart problems and cancer.

Employees running the study filed the data in the company's internal archives without reporting anything to the FDA, the Star Tribune reports. But the company looked at and recorded each adverse event from the review years later in 2013, Dr. Richard Kuntz, Medtronic's chief scientific, regulatory and medical officer, told the newspaper.

In 2008, employees running the RCR identified the events "very clearly in the database," Kuntz said. "When they kind of discovered through discussions that this just wasn't going to be a pathway to lead to an expanded (approval), they stopped the project and closed out the study."

Medtronic did not report the data to the FDA until 2013 after reports of grave complications with Infuse surfaced. The company filed four death reports and an injury report that year, and asked the FDA how to share the rest of the side effects. The agency let the company file a summary instead of a detailed report of the remaining adverse events "because this information was dated, and didn't reflect new public health concerns," an FDA spokesman told the newspaper in an email.

Medtronic also submitted a sixth individual injury report in 2014 and a 76-page summary report with 1,039 side effect reports. The FDA blacked out the number of injuries, though, and only showed a three-sentence summary of problems linked to Infuse.

During the time that the company sat on study data, Medtronic hired Yale University researchers to study Infuse. The researchers did not get data from the company's buried RCR until they were almost finished with their analyses. Scientists opted to use data from clinical trials instead, even though Medtronic contacted them to see if they wanted the RCR data.

The company has dealt with fallout regarding its product since 2008. Medtronic was subpoenaed by the U.S. attorney's office in Massachusetts in 2008 over Infuse. And the Senate Finance Committee asked the company for information on "adverse postoperative events" associated with the product, according to the Star Tribune story.

Medtronic also faces more than 6,000 injury claims from patients who got Infuse. Insurance giant Humana ($HUM) also filed a racketeering suit against the company over Infuse.

To some legal experts, Medtronic and the FDA's behavior can't be explained away. "In some ways what's curious about this particular case is the FDA's behavior, even more than Medtronic's behavior," David Prince of Mitchell Hamline School of Law told the newspaper. Infuse "is a widely, routinely used product," Prince said. "When you get that kind of feedback from the marketplace telling you things are going wrong with some frequency, to just shrug and say, 'Well, we won't look at it any further' is the ostrich approach. You're just burying your head in the sand."

But Medtronic is standing by its actions. The company put out a statement on Sunday slamming the Star Tribune article, saying that it "makes insinuations that are false" and that it "fails to include important information regarding the RCR and Medtronic's actions."

Medtronic "never did an analysis back in 2008" when the RCR review was concluded, so "there was no real sense of what was in the data," spokesman Eric Epperson told FierceMedicalDevices. "We take responsibility that it should have been handled differently, but there was no attempt to cover up data," Epperson said.

Plus, the company has updated its clinical policies and training to improve reporting, Epperson said. And Medtronic eventually reported RCR data to the FDA, the company said in a statement. "We are committed to, and have led the industry in, transparency--transparency regarding our business, our interactions with physicians, and the disclosure of clinical evidence related to our therapies--in particular with Infuse," the company said.

Medtronic has a lot on the line with the product. Sales for Infuse slumped a bit in recent years after peaking at $750 million in 2011. But the product charted double-digit growth in the U.S. in the company's most recent quarter.

- read the Star Tribune story
- here's Medtronic's statement

Editor's note: This story was updated with information from an interview with Medtronic.