Medtronic Begins Chronic Back Pain Treatment Trial

Minneapolis, Minn.-based medical device giant Medtronic Inc. has enrolled the first patient in the Subqstim II pivotal clinical trial to pursue U.S. Food and Drug Administration (FDA) approval of peripheral nerve stimulation (PNS), also known as subcutaneous nerve stimulation (SQS), for the reduction of chronic, intractable post-surgical back pain.

PNS involves an implant of electrical leads just under the skin of the lower back. These leads are connected to a stimulator, which delivers mild electrical impulses to the nerves, interrupting pain signals traveling through the nervous system to the brain. Medtronic received CE mark for the first 16-electrode, fully implantable system for the percutaneous delivery of PNS in the management of chronic back pain in May 2011. Currently, the FDA has not approved any PNS treatment involving a fully implantable system.

The Subqstim II pivotal study is a randomized, controlled, blinded, parallel arm, multicenter trial to assess the safety and efficacy of PNS for chronic, intractable post-surgical back pain. The study will recruit up to 323 people at 30 U.S. centers who will receive PNS using a Medtronic neurostimulation system. Subjects will be randomized to a treatment or control group for the first three months and will continue to participate in open label follow-up for up to five years.

“The Subqstim II pivotal study will provide new information about subcutaneous nerve stimulation as a potentially valuable treatment option for U.S. patients with chronic, intractable back pain who have found insufficient relief with other treatment options,” said the study’s coordinating investigator, George Mandybur, M.D., associate professor and director Stereotactic and Functional Neurosurgery at the University of Cincinnati and a neurosurgeon with the Mayfield Clinic.

The first enrollments were performed by principal investigators Yeshvant Navalgund, M.D., of DNA Advanced Pain Treatment Center in Greensburg, Pa., and D. Joseph Meyer, M.D., Ph.D., of Columbia Interventional Pain Center in Columbia, Miss.

“Study findings will provide an unprecedented understanding of how leads placed in the subcutaneous tissue layer work with neurostimulation devices to help patients manage their chronic back pain,” said Navalgund.

The Subqstim II pivotal study is the latest in a series of clinical trials sponsored by Medtronic to generate a comprehensive portfolio of evidence demonstrating the clinical and economic value of its neurostimulation systems for the management of chronic pain. Medtronic recently initiated the Subqstim I post-market study in Europe, Israel, Australia and Canada to evaluate the effectiveness of PNS plus optimal medical management (OMM) for low back pain, compared to OMM alone in patients with failed back surgery syndrome (FBSS). In January, the company announced the beginning of Promise, a prospective, randomized study of multicolumn implantable lead stimulation for predominant low back pain. Promise is the first-ever, large-scale study comparing the effectiveness of Medtronic neurostimulation therapy with Specify 5-6-5 multicolumn surgical leads plus OMM, to OMM alone in patients with FBSS and predominant low back pain.

“Chronic back pain affects a significant number of adults in the United States, and if the Subqstim II pivotal trial results are positive, we plan to pursue FDA approval to make this potential treatment option available to patients who may benefit,” said Julie Foster, general manager and vice president of pain stimulation and targeted drug delivery in the neuromodulation business of Medtronic.

It is estimated that 100 million U.S. adults live with chronic pain, and it is the most prevalent type of chronic pain, affecting approximately 10 percent of the U.S. population. Many patients suffering from chronic pain following spine surgery receive oral medications and other therapy, but clinical experience finds many of these patients fail to obtain adequate relief and will require additional interventions.

Medtronic joins other companies in the multi-billion dollar neurostimulation market, including Boston Scientific, which recently gained FDA approval for Precision Spectra, its spinal cord stimulation device.