Al Franken (D-MN) requested detailed information about Medtronic from federal investigators, according to a Reuters report.
The Senator asked for information about Infuse after the Minneapolis Star Tribune published a special investigation into the previously reported issues with clinical studies that lead to the FDA's approval in 2002. The FDA granted approval after reviewing clinical trial studies, but not all the data on adverse events was sent to the agency at that time. The Senator also asked Medtronic to clarify the information given to the FDA and inquired about training staff to report adverse events.
Medtronic plans to discuss these issues with Sen. Franken and claimed allegations in the Star Tribune report were false.
Sen. Franken also sent a letter to the FDA for information about the issue; the FDA plans to respond to Sen. Franken directly, according to the report.
The renewed interest in the Infuse case comes long after the spine community initially addressed the issue. The Spine Journal dedicated an entire 2011 issue to studies outlining potential issues with the Infuse product, especially with off-label use. The company also addressed mishandling clinical study information — Medtronic claims data about adverse events was "misfiled" and not considered during the FDA clearance process.
Since then, the Yale Open Data Access Project published two studies in the Annals of Internal Medicine about the safety and effectiveness of Infuse based on data that included the adverse events. The studies found Infuse produced similar effectiveness, but Infuse patients where more commonly associated with pain and cancer postoperatively.
Medtronic underwrote the $2.5 million YODA project. Since then, The Spine Journal has changed its policies to disclose financial relationships between physician researchers and device companies associated with the studies. Sales of Infuse dipped in the United States after the YODA studies were published, but some surgeons continue to use the product.
At its zenith, Infuse was used in 28.1 percent of all spinal fusions. Surgeons stopped using it for various reasons, but continue to use it for some procedures:
• Open posterior fusion: 7.8 percent of surgeons
• Open interbody surgery: 6.2 percent of surgeons
• Minimally invasive interbody surgery for degenerative spondylolisthesis: 12.1 percent of surgeons
A North American Spine Society survey shows 85 percent of surgeons had read one or both of the YODA articles and felt:
High concern for cancer risk: 3 percent in 2013 vs. 4.7 percent in 2014
Moderate concern: 16 percent in 2013 vs. 14.8 percent in 2014
Mild concern: 58 percent in 2013 vs. 54.2 percent in 2014
None: 24 percent in 2013 vs. 26.4 percent in 2014
The numbers were similar for concern in retrograde ejaculation and cervical swelling. Most respondents had high concern for cervical swelling. Among other complications, there was a decreased high concern and relative increase in mild concerns. Finally, they looked at utilization. In ALIF, the respondents reported:
• Always — 40 percent in 2013 vs. 37.3 percent in 2014
• Occasionally — 17 percent in 2013 vs. 14.3 percent in 2014
• Rarely — 12 percent in 2013 vs. 13.7 percent in 2014
• Never — 15 percent in 2013 vs. 18.1 percent in 2014
However, when asked whether the physicians significantly changed their use patterns for BMP, 41 percent said they decreased their dose and frequency in 2013, compared to 21.8 percent in 2014. Seventeen percent decreased frequency in 2013, compared with 12.3 percent in 2014. Twelve percent just decreased dosage in 2013, compared with 7.3 percent in 2014. The most interesting was those who didn't change; 55.7 percent reported no change in 2014, compared with just 30 percent in 2013.
The new reports about Infuse don't present any new information about the product or the company's involvement since the "misfiled" information was released.