Mainstay Medical

Mainstay Medical is a medical device company focused on commercializing its innovative implantable ReActiv8 neurostimulation system for treating chronic low back pain associated with multifidus muscle dysfunction. ReActiv8 is a restorative neurostimulation therapy that helps restore functional spine stability and reduces pain by electrically stimulating the nerves responsible for activating the key muscles that stabilize the lower back.

The ReActiv8 system consists of an implantable pulse generator (IPG) and leads that deliver stimulation to the medial branch of the dorsal ramus nerve to elicit episodic multifidus muscle contractions. Patients undergo stimulation sessions twice a day for about 30 minutes each, aided by an external programmer to customize settings and a wireless remote control. Over time, this stimulated muscle activation aims to help the brain relearn how to control these stabilizing muscles, allowing the body to recover from chronic low back pain.

ReActiv8 secured CE mark approval in Europe in 2016 and US FDA approval in 2020. As of March 2024, it is commercially available in the European Economic Area, Australia, the UK, and the US. A landmark study published in March 2024 reported ReActiv8's long-term efficacy, durability, and safety over five years in treating intractable chronic low back pain. In November 2022, real-world data from an interim analysis also demonstrated statistically significant improvements in pain, disability, and quality of life measures among ReActiv8 patients.