A novel device that stimulates the vagus nerve was associated with encouraging DAS28-CRP response in a small cohort of patients with rheumatoid arthritis, according to findings presented at the EULAR Annual Congress.
“Our pilot study suggests this novel MicroRegulator device is well tolerated and reduces signs and symptoms of rheumatoid arthritis,” Mark C. Genovese, MD, James W. Raitt Professor of Medicine and director of the Rheumatology Clinic in the division of immunology and rheumatology at Stanford University Medical Center, said in a press release.
Activation of the neuroimmune reflex using an electrical vagus nerve stimulation was tested previously in a 17-participant proof-of-concept study. In that study, the researchers used a reprogrammed epilepsy stimulator in an RA cohort. For the current study, Genovese and colleagues developed a novel device known as the MicroRegulator (SetPoint Medical) to be tested in 14 patients with active RA.
A novel device that stimulates the vagus nerve was associated with encouraging DAS28-CRP response in a small cohort of patients with RA, according to findings.
Eligible participants had previously shown an insufficient response to two DMARDS or JAK inhibitors with two different mechanisms of action.
Three weeks after the device was implanted, three study patients were stimulated for 1 minute once daily. The study did not proceed until a safety review board approved the procedure. Following approval, the remaining 11 patients underwent implantation and randomly assigned 1 minute of a sham stimulation, stimulation once daily, or stimulation four times daily for 12 weeks.
Clinical efficacy as assessed by DAS28-CRP response and contrast-enhanced MRI served as the primary outcome measures. The researchers also used an ex-vivo bioassay to evaluate pharmacodynamic response.
At the 12-week assessment, the mean DAS28-CRP change was –1.44 for the open-label once-daily group; –1.24 for the once-daily study group; 0.38 for the four-times daily group; and 0.16 for the sham group.
The safety profile showed no treatment-emergent serious adverse events. In terms of other adverse events, one patient experienced left vocal cord paralysis, while one experienced Horner’s syndrome. Both events resolved without significant sequelae, according to the findings.
A strong EULAR response was reported in four of six patients who were stimulated once daily. However, no change in MRI measures of synovitis or osteitis were observed at 12 weeks.
Other findings showed a correlation between RAMRIS erosion scores and EULAR response. Among EULAR responders, the change in RAMRIS was –2.2, while the change in EULAR non-responders was 2.4.
The researchers confirmed the pharmacodynamic response to vagus nerve stimulation in active treatment groups with a decrease of 30% or more in levels of IL-1beta, IL-6, and TNF at 12 weeks’ follow up.
“These data support the study of this device in a larger placebo-controlled study as a novel treatment approach for rheumatoid arthritis and possibly other chronic inflammatory diseases,” Genovese said. – by Rob Volansky
Genovese M, et al. LB0009. Presented at: EULAR Annual Congress; June 12-15, 2019; Madrid.
Disclosure: Genovese reports receiving grant or research support and consulting for Genentech/Roche, RPharm and Sanofi/Genzyme.