Cancer Findings Raise More Medtronic Infuse WorriesApr 16, 2012 | Parker Waichman LLP
A study presented this past November raised serious concerns about cancer risks that could be associated with Medtronic Inc.'s Infuse Bone Growth product. The study was conducted by long-time Infuse critic, Dr. Eugene Carragee, and found that within a year of implantation, cancer risks more than doubled in Infuse patients. At three years after implantation, the increased cancer risk grew to nearly five-fold.
Carragee's cancer study, presented at the annual North American Spine Society meeting in Chicago, isn't the first time the Stanford University professor and Spine Journal editor has raised concerns about Infuse. This past summer, he edited an entire issue of The Spine Journal dedicated to rhBMP-2 products which raised serious questions about the validity of the research that was used to gain regulatory approval of Infuse. One of the articles included in the journal, co-authored by Carragee, found that Medtronic-paid surgeons had failed to report serious complications from Infuse, including:
• Sterility in men
• Bone dissolution
• Worsened back and leg pain
Carragee's cancer study pooled clinical trial data from Infuse, and a high-dose version of the same protein, called Amplify. Medtronic also developed Amplify, but failed to garner U.S. Food & Drug Administration (FDA) approval for the product because of concerns it could increase cancer risks.
According to a report from The New York Times, Carragee’s analysis of Medtronic trial results for Amplify showed a significantly higher number of cancers in the study group that received the product when compared to a control group that received a bone graft as part of a spinal fusion. At three years after surgery, there were 20 cancers in the Amplify group versus five cases in the bone graft group.
Carragee pointed out that the Amplify findings could be important for Infuse patients, many of whom received Infuse in off-label procedures. Doctors often administered Infuse off-label at levels significantly above the recommended dosages, ones that approach or exceed the amount of rhBMP-2 found in a dose of Amplify, he said.
It is estimated that roughly 85% of Infuse procedures involve off-label use.
One interesting note, during his presentation, Carragee pointed out that the industry-sponsored studies upon which his analysis was based neglected to discuss the association between rhBMP-2 and cancer.