Off-Label Use of Bone Growth Proteins in Children Questioned

According to a recent study published in the Journal of the American Medical Association (JAMA), almost one tenth of U.S. children undergoing arthrodesis, a type of spine fusion surgery, are injected with bone morphogenetic (bone growth) proteins (BMPs) that have not been approved for use by the U.S. Food and Drug Administration.

Off-label use of medical therapies is legal in the United States (although companies marketing their products for off-label uses is not), but researchers are concerned that “augmentation beyond instrumentation and autograft bone grafting in pediatric spinal arthrodesis” is unnecessary. BMPs are approved for limited use in adults when healing might not occur at an optimal rate. The use of BMPs, researchers reported, raises concerns about the possible onset of cancer, wound dehiscence (where the wound opens along the surgical suture), spinal stenosis (an abnormal narrowing of the spinal cord), and respiratory complications.

Last year, Medtronic Inc. faced a lawsuit over its bone growth device Infuse, also known as BMP-2. Physicians on the company payroll had failed to report serious complications arising from Infuse, which included carcinogenesis, sterility in men, infections, and bone dissolution.

Emily Dodwell, M.D., a lead researcher on the JAMA study, told Reuters Health that it is unclear whether children would suffer the same side effects, but the ways in which BMPs react with still-growing skeletons was concerning. Her study did not specify particular products by brand. There also is no reliable existing data on whether BMPs help children, who heal more quickly and effectively from spinal surgery than adults.

The researchers looked at approximately 4,100 hospitals in the national registry for their study. Out of 8,000 arthrodesis surgeries of patients under the age of 18, 9.2 percent involved BMPs. In cases where BMPs were used, patients’ hospital bills were an average of $47,136, compared to $43,126 when surgeons didn’t use the product.

There was no immediate difference between the recovery of children and the use of BMPs, but Dodwell and her colleagues stated that long-term effects were the main concern. She and her team will continue to monitor the progress of these children through a different registry once they leave the hospital.

Photo of Medtronic’s Infuse bone graft system courtesy of the Maher Law Firm.