Medtronic Inc. said Wednesday that it will fund two independent studies of a controversial bone-growth product used in back surgery.

The Fridley-based medical technology giant has agreed to grant Yale University researchers $2.5 million to determine the safety and effectiveness of its Infuse product, which is used in spine fusion surgery. Leading the effort is Dr. Harlan Krumholz, a nationally known physician and advocate of patient safety and transparency in clinical studies.

Yale will work with two clinical research organizations to conduct separate reviews of data on the product.

Medtronic's initiative came after the Spine Journal, a major publication for back surgeons, published a study last month that found researchers with ties to Medtronic frequently failed to report complications associated with Infuse in clinical studies.

"When questions were raised a month ago, we asked ourselves what would be the best way to handle this," said Chris O'Connell, executive vice president and president of Medtronic's Restorative Therapies Group. "Instead of getting into a point-by-point debate with authors of a particular journal, we decided to take the high road and seek out a third party, a completely unbiased and independent organization that could do a systematic review of Infuse."

The Spine Journal study was the latest chapter in a long-standing controversy over perceived conflicts of interest between Medtronic and doctors who are paid by the company as consultants -- relationships that have drawn investigations by Congress and the U.S. Department of Justice.

Approved for use by the Food and Drug Administration in 2002, Infuse was a blockbuster product for Medtronic until recently, as the number of back surgeries has slowed in a tough economy. The bioengineered material can "grow" bone when inserted in a thimble-like cage between the vertebrae in an effort to mitigate back pain.

But the Spine Journal articles indicate that complications associated with the procedure -- excessive bone growth, cancer, male sterility, bladder dysfunction, and leg and back pain -- have been under-reported in clinical research.

Medtronic said it will provide Yale researchers with patient data from the 44 studies that have been conducted with Infuse, as well as reports of complications submitted to the FDA. Yale will then name a 13- to 15-member panel of experts and commission two clinical research organizations to analyze the data, with no participation from Medtronic. Yale is expected to complete the review within six months.

Beyond that, Medtronic agreed with Yale to develop a new program that would publish Infuse data on a website for use by researchers, a move the company called "unprecedented in the medical industry."

Aiming for transparency

The announcement by Medtronic is the first major initiative put forth by its new CEO, Omar Ishrak. Ishrak has not been made available for media interviews, but O'Connell said he was a catalyst in the effort. "He had just started his job when the [Spine Journal articles appeared] and he very much was the leader in saying this is what we want to do -- we need to stand for safety and integrity."

Dr. Eugene Carragee, editor of the Spine Journal, said the Yale initiative "appears to be a big first step in the right direction." Patients and doctors "deserve no less than a fully transparent accounting of the various [Infuse studies] with analysis by non-conflicted reviewers," he said in a statement.

However, Carragee cautioned that because some of the initial studies on Infuse were "flawed," analyzing that particular data will have little value. "Unfortunately, the Yale University researchers will not be able to fix the study design flaws and assessment biases that were used in some of the original studies," he said.

In addition, even though the top use of Infuse is in a type of back surgery called posterior interbody fusion, a randomized study of this particular use was halted due to complications. "Consequently, the Yale group will still have very little controlled data to judge actual safety of the product," Carragee said.

Krumholz, the physician leading the Yale effort, could not be reached for comment. A cardiologist and native Midwesterner, he is known for measuring outcomes in health care.

In a statement, Krumholz said the project "is intended to establish a landmark model for data transparency -- a breakthrough in balancing the needs of industry with the public's desire for an independent review of the complete set of data."

If the project is successful, he said, it could become standard practice in medicine.

Janet Moore • 612-673-7752