Mainstay Medical Announces Release of Two-Year Patient Outcome Data from ReActiv8-B Clinical Trial Demonstrating Long-Term Efficacy of ReActiv8® Restorative Neurostimulation

Data Shows Compelling Efficacy and Safety, and Improvement in All Key Pain and Disability Measures Compared to One-Year Study Results

January 6, 2022

Dublin, Ireland-(BUSINESS WIRE)–Mainstay Medical Holdings plc today announced the release of two-year patient outcome data from its pivotal ReActiv8-B clinical trial. The data, published in the journal of the International Neuromodulation Society, Neuromodulationconfirm the efficacy and safety of ReActiv8 restorative neurostimulation, and also demonstrate compelling long-term durability and improvement over time on key outcome measures in the treatment of intractable chronic low back pain.

On virtually all key measures of effectiveness, the 2-year data showed improvements over the 1-year patient visit data. To note :

Results measurement Result at 2 years (N = 156) Result at 1 year (N = 176)
Patients reporting pain intensity (VAS score) reduced by 50% or more from baseline 71% 64%
Patients reporting a reduction of more than 20 points in the Oswestry Disability Index 61% 57%
Patients reporting a VAS score 65% 52%
Patients taking opioids at baseline who voluntarily eliminated or reduced opioid use 60% 48%

Dr. Chris Gilligan, director of the Brigham and Women’s Spine Center at Brigham and Women’s Hospital and assistant professor of anesthesia at Harvard Medical School, said: Recently published data from the ReActiv8-B clinical trial showed clinically significant improvements in pain and function in patients with refractory chronic low back pain who received two years of neurostimulation. Patient pain scores have significantly decreased from an average of 7.3 to 2.4 and are maintained for 2+ years with ongoing data collection. These long-term data are extremely important and encouraging given the chronic and refractory nature of this condition.

“These impressive results represent an important milestone for Mainstay, as the profound improvements in patient outcomes we have seen from baseline through 1 to 2 years validate the restorative nature of the therapy and represent a new paradigm among treatments. available for patients with chronic incurable low back pain, said Jason Hannon, CEO of Mainstay Medical. “We are proud to have the only commercially available device with a strong safety profile and long-term peer-reviewed evidence supporting rehabilitation in this severely affected patient population, evidence that continues to expand to through multiple clinical trials.

The full publication can be downloaded free of charge at The ReActiv8-B trial patient cohort continues to be evaluated to generate additional longer-term efficacy data.

About ReActiv8®

ReActiv8 is an implantable medical device designed to treat adults with chronic intractable low back pain (CLBP) associated with multifidus muscle dysfunction. Multifidus muscle dysfunction may be demonstrated by imaging or physiological testing in adults who have failed treatment, including pain medications and physical therapy, and who are not candidates for spinal surgery. ReActiv8 has received regulatory approval in multiple geographies and is commercially available in the European Economic Area, Australia, the United Kingdom and the United States.

About the ReActiv8-B clinical trial

The ReActiv8-B clinical trial is an international, multicenter, prospective, randomized, active simulation-controlled, blinded, one-way crossover trial conducted under an investigational device exemption (IDE) from the FDA. A total of 204 patients with chronic low back pain refractory to physiotherapy and medical management were implanted with ReActiv8 at leading clinical sites in the United States, Europe and Australia and randomized 1:1 for treatment or a control. In the treatment group, the ReActiv8 pulse generator was programmed to deliver electrical stimulation believed to cause episodic contractions of the multifidus muscle. In the control group, the ReActiv8 device was programmed to provide a low level of electrical stimulation. Following assessment of the primary endpoint at 120 days, patients in the control group were switched to receive similar levels of electrical stimulation as the treatment group.

Clinical trial funded by Mainstay Medical. Dr. Chris Gilligan, principal investigator of the trial, is a consultant to Mainstay Medical. Information about the study is available at

About Mainstay Medical

Mainstay Medical is a medical device company focused on commercializing its innovative Restorative Neurostimulation™ implantable system, ReActiv8®, for people with disabling mechanical CLBP. Mainstay Medical is headquartered in Dublin, Ireland, and has subsidiaries operating in Ireland, the United States, Australia, Germany and the Netherlands.

Further information can be found at

Forward-looking statements

All statements in this announcement other than statements of historical fact are, or may be deemed to be, forward-looking statements. These forward-looking statements may include, but are not limited to, statements regarding the Company’s current intentions, beliefs or expectations regarding, among other things, the Company’s business efforts and performance, financial condition, funding strategies , product design and development, regulatory applications and approvals, and reimbursement terms.

Forward-looking statements involve risks and uncertainties and are not guarantees of future performance. Actual results may differ materially from those described or implied by the forward-looking statements. A number of factors could cause actual results and developments to differ materially from those expressed or implied by the forward-looking statements herein, including, without limitation, the possibility that future clinical results may not be consistent. previous reported results; the possibility that business results will not meet expectations; and other risks and uncertainties included in the Company’s Annual Report for the fiscal year ended December 31, 2020, which should be read in conjunction with the Company’s public information (available on the Company’s website, The forward-looking statements contained herein speak only as of the date of this announcement.


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