Study: 17% off-label use of bone graft substitute in spine

Investigator says spine industry must take a critical look at off-label use of bone-fusion proteins.

TORONTO — Investigators at the Cleveland Clinic quantified on- and off-label use of a recombinant human bone morphogenetic protein for spine fusion surgery in Medicare and non-Medicare patients, estimating the product’s sales at about three times greater in 2007 than in 2003.

During those years, they saw off-label use of Infuse (recombinant human bone morphogenetic protein-2, Medtronic) decrease in Medicare-aged patients but increase for non-Medicare patients, a trend that has investigators concerned.

“We estimated that the sales of Infuse went up over $760 million” from 2003 to 2007, Isador H. Lieberman, MD, FRCSC, said.

For the retrospective analysis, investigators sought to delineate on- and off-label usage trends for Infuse and explore how they were reflected in Medicare and non-Medicare patient populations, Lieberman said at the North American Spine Society 23rd Annual Meeting, here.

Estimates used

The study, which involved several different parameters and assumptions, estimated Infuse usage from Wall Street volume estimates and other information from the product’s manufacturer and databases.

To determine Infuse usage in the Medicare population, Lieberman and colleagues analyzed data derived from the Medicare Provider Analysis Review database (MedPAR). Actual sales data for Infuse was unavailable, Lieberman noted.

For sales, “The unit figure assumes a charge of $4,500 per unit of Infuse,” he said. “Some centers may have been paying less. Some centers may have been paying more for it. We also used the assumption the annual growth rate of lumbar fusion is about 9.5% per year,” he said.

Increased sales

According to Lieberman, overall Infuse sales in those 5 years rose substantially from $204 million to $763 million as projected from published information.

For the same period, overall sales in Medicare vs. non-Medicare populations increased as well, changing in the non-Medicare sector from $149 million to $681 million. Sales for the Medicare sector increased from $54 million to $79 million, although the percentage of total units sold decreased annually in the Medicare patient population, Lieberman pointed out.

Usage trends

For on- vs. off-label Infuse use as a percentage of total sales, investigators noted an increase in on-label use among the Medicare population from about 9,200 to about 13,000 units, or 7.9% of Infuse sales. Off-label use of Infuse also increased in that group, but the percentage of total sales actually went down from 6.5% to 2.5%, Lieberman said.

On-label non-Medicare Infuse usage rose to about 127,200 units in 2007 and off-label use increased to about 24,200 in 2007 or 14.3%. During the period analyzed, 17.3% of all Infuse usage was off-label, according to Lieberman.

“I think these data really emphasize we have to critically study the off-label use of bone biologics,” he said.

For more information:
Isador H. Lieberman, MD, FRCSC, is the chairman of the Spine Care Center at Cleveland Clinic Florida. He can be reached at, 2950 Cleveland Clinic Blvd., Weston, FL 33331; 954-659-5630; e-mail: lieberi@ccf.org. He receives royalties from Stryker, DePuy, Axiomed, Crosstrees, Trans1, Mazor, Merlot OrthopediX, he owns stock in Axiomed, Crosstrees, Trans1, Mazor and Merlot OrthopediX stock, he is a paid consultant to Axiomed, Trans1, Mazor, Merlot OrthopediX and Kyphon and he receives research support from Trans1, Mazor, Kyphon, Medtronic and Orthovita.

Reference:
Mroz TE, Yamashita T, Lieberman IH. The on- and off-label use of rhBMP-2 (Infuse) in Medicare and non-Medicare patients. #79. Presented at the North American Spine Society 23rd Annual Meeting. Oct. 15-18, 2008. Toronto.