Yale's Independent Review of Medtronic's Infuse Described as Inherently FlawedJun 7, 2013
A group of Yale University researchers commissioned by medical device maker Medtronic to conduct independent studies of its Infuse Bone Graft products are expected to release their results this month.
The Spine Journal first disclosed, in a June 2011 article, that Medtronic-paid researchers had deliberately failed to report serious potential complications caused by Infuse bone graft products in spinal surgery. Bloomberg Businessweek jumped on the bandwagon, reporting that Medtronic had paid about $210 million in royalties and consulting fees to doctors and researchers who had authored at least 11 medical journal reports about Infuse. Senate investigators charged that Medtronic deliberately manipulated Infuse studies to mitigate any adverse reactions to the bone graft product, as well as to promote off-label uses.
The new CEO of Medtronic, Omar Ishrak, announced on August 3, 2011, that Medtronic had hired Yale University and Dr. Harlan Krumholz, a professor at Yale through their Yale University Open Data Access (YODA) Project, to assemble a group of experts who would commission two outside research organizations to independently review the safety and efficacy of Medtronic’s Infuse.
Dr. Krumholz would perform the Yale review while a steering committee of medical experts appointed by Yale would be led by Dr. Ezekiel Emanuel, Chair of the Department of Bioethics at the National Institutes of Health.
Medtronic made a $2.5 million grant to Yale University for the study.
"The two groups will work independently to answer the same questions: What's the quality of the data and what can you infer about the benefits and harms," Krumholz said. "That's pretty hard to rig."
However, as noted at the time by Dr. Eugene J. Carragee, editor of the Spine Journal, several major challenges to “true transparency and patient safety remain.”
Dr. Carragee wrote that the partnership between Medtronic and Yale was a “big first step in the right direction,” – but at the same time, the Yale study, no matter what else, would be inherently flawed – in three specific ways.
A study must be created without bias, Dr. Carragee wrote. “Later analysis of original flawed data, such as in some of the industry-sponsored [Infuse] studies, will have little value. Unfortunately, the Yale University researchers will not be able to fix the study’s design flaws and assessment biases that were used in some of the original studies.”
In addition, because the original Medtronic-sponsored research did not report any adverse events, the voluntary reporting by practicing surgeons was handicapped by surgeons and patients not recognizing many of the complications were related to the product, Dr. Carragee said.
Finally, the most common use of Infuse today is posterior lumbar fusions and the randomized trial on this particular use was halted early on because of complications and adverse events, Dr. Carragee noted. “Consequently, the Yale group will still have very little controlled data to judge actual safety of the product.”
The U.S. Food and Drug Administration (FDA) approved Infuse in 2002 for use in fusing damaged vertebrae in the lower spine. Although Infuse was not approved for use on the upper, or cervical, spine, it is widely used in cervical spine fusions, according to a Businessweek report. Businessweek noted a July 2008 FDA warning of serious complications associated with Infuse when used in cervical spine fusions. These include excessive swelling in the neck, compressed airways, difficulty breathing, problems swallowing, and nerve damage.