June 22, 2020 DUBLIN–(BUSINESS WIRE)–Mainstay Medical Holdings plc (“Mainstay” or the “Company”) today announced that the U.S. Food and Drug Administration (FDA) has approved the Company’s Premarket Approval (PMA) application for ReActiv8®, its implantable neurostimulation system to treat intractable chronic low back pain. Jason Hannon, CEO of Mainstay, said: “I am so proud of our team …