FDA Panel Disapproves of Expanded Stryker Putty Use

A U.S. Food and Drug Administration advisory panel has recommended that Stryker Corp.’s bone-growth OP-1 putty for spinal surgery not be approved by the agency for expanded use. The putty already is cleared for limited use in certain surgeries to treat back pain.

Concerns among the panel, which voted 6-1, include possible bias during the company’s clinical trial and lack of attentiveness to scientifically studying safety and effectiveness.

“I have major concerns about the biases in this study,” including reliance on patients’ self-reported satisfaction while at the same time knowing which group they were put in, said Kathleen Propert, a panelist and statistician at the University of Pennsylvania.

Stryker’s main study compared the putty to a procedure in which surgeons take a piece of bone from a patient’s hip and use it to fuse the vertebrae.

OP-1 putty is an alternative to autograft in compromised patients requiring revision posterolateral lumbar spinal fusion, for whom autologous bone and bone marrow harvest are not feasible or are not expected to promote fusion. Examples of compromising factors include osteoporosis, smoking and diabetes.

The FDA is not obliged to follow panel recommendations, but does in most cases.