HealthDay News – Vagus nerve stimulation in patients with rheumatoid arthritis (RA), specifically targeting the inflammatory reflex modulating tumor necrosis factor (TNF) production, appears to reduce systemic inflammation and decrease RA symptoms. These findings were published in the Proceedings of the National Academy of Sciences.
Kevin Tracey, MD, president of the Feinstein Institute for Medical Research in Manhasset, N.Y., and colleagues implanted a vagus nerve stimulation (VNS) device in 17 patients with RA. Seven were in the earlier stages of the disease and had not responded to methotrexate. The rest had more advanced disease and had failed to improve after trying at least two biologic drugs.
High Yield Data Summary
- Vagus nerve stimulation in patients with RA decreased TNF production and decreased standardized measures of RA disease severity
Six weeks after the VNS devices were implanted, most of the patients were improving. The researchers found that 71.4% had at least a 20% improvement in their symptoms — including a reduction in the number of tender, swollen joints.
In the group with early-stage RA, 57.1% had at least a 50% improvement; that was true for 28.6 percent of patients with more advanced disease.
Blood levels of tumor necrosis factor, interleukin-1β, and interleukin-6 declined.
“This first-in-class study supports a conceptual framework for further studies of electronic medical devices in diseases currently treated with drugs,” the authors write. “Larger clinical trials in RA can be designed and powered to assess clinical efficacy, but our findings encourage pursuing this strategy.”
Summary and Clinical Applicability
These results suggest that vagal stimulation may be future potential treatment strategy in RA and in other cytokine-mediated inflammatory disorders.
“the inhibition of TNF during electrical stimulation and the significant clinical responses shown give evidence that the clinical mechanism is mediated by the inflammatory reflex,” the authors concluded.
Limitations and Disclosures
Individual cohorts had small number of subjects (n=1-, n=7). Placebo effect cannot be excluded as patients were aware of treatment status.
SetPoint Medical, a company that is developing neuromodulation therapies for RA and other diseases, funded the study. Tracey is a consultant to the company, and several of his co-researchers are SetPoint employees.
Koopman FA, Chavan SS, Miljko S, et al. Vagus nerve stimulation inhibits cytokine production and attenuates disease severity in rheumatoid arthritis. Proc Natl Acad Sci USA. 2016; doi: 10.1073/pnas.1605635113