The study involved implanting signal generator connected to the vagus nerve. Stimulation was found to reduced the production of proteins called cytokines.
“This is a real breakthrough in our ability to help people suffering from inflammatory diseases,” said Dr Kevin Tracey, CEO of the Feinstein Institute for Medical Research in New York. “While we’ve previously studied animal models of inflammation, until now we had no proof that electrical stimulation of the vagus nerve can indeed inhibit cytokine production and reduce disease severity in humans. I believe this study will change the way we see modern medicine, helping us understand that our nerves can, with a little help, make the drugs that we need to help our body heal itself.”
The Feinstein Institute worked with the University of Amsterdam, which lead the study, and a Californian company called SetPoint Medical.
In the study, a stimulation device was surgically implanted on the vagus nerve then activated and deactivated over 84 days. Patients were assessed for tender joints, swollen joints and serum C-reactive protein levels. Qualitative measures included the patient’s own assessment and the assessment of medical staff.
During the treatment, current up to 2mA (depending on what could be tolerated) was delivered in 250μs pulses at 10Hz for 60s once a day, or four times daily in some patients.
Of 17 patients with active rheumatoid arthritis in the study, “several patients that had failed to respond to multiple therapies, including biologicals with different mechanisms of action, demonstrated robust responses”, said the Feinstein Institute. “The findings indicate that active electrical stimulation of the vagus nerve inhibits TNF production in rheumatoid arthritis patients and significantly attenuates rheumatoid arthritis disease severity.”
TNF is the cytokine ‘tumour necrosis factor’ which promotes inflammation and has been associated with autoimmune diseases including rheumatoid arthritis.
Several patients reported significant improvements, said Feistein, including some who had previously failed to respond to any other form of pharmaceutical treatment – and no serious adverse side effects were reported.
Results are published as ‘Vagus nerve stimulation inhibits cytokine production and attenuates disease severity in rheumatoid arthritis” in the Proceedings of the National Academy of Sciences.
While focused on rheumatoid arthritis, the researchers suggest the trial results may have implications for patients with other inflammatory diseases including Crohn’s, Parkinson’s and Alzheimer’s.
SetPoint is developing platform consisting of a neuromodulation implant for the vagus nerve and iPad prescription app intended to treat a variety of immune-mediated inflammatory diseases. As well as rheumatoid arthritis, it is involved in a clinical study for Crohn’s disease.
Vagus nerve stimulation through an implanted device similar to a pacemaker is a standard way to lessen the effects of epilepsy.
