MAINSTAY MEDICAL, a start-up device company targeting lower back pain, will relocate to Ireland following a $20 million fundraising led by Irish VC group Fountain Healthcare Partners.

The company, previously based in Minneapolis in the US, has developed a device to address chronic lower back pain through electrical stimulation.

Chief executive Peter Crosby says the funding will finance clinical trials and subsequent certification for marketing in Europe. Further funding would be required to see the company through to the conclusion of the US regulatory process.

Mainstay, founded by serial entrepreneur Dan Sachs, targets what is known as chronic non-specific lower back pain, an often debilitating condition with no identifiable anatomical cause, which is estimated to affect as many as 7.5 million people in the US alone.

Mr Crosby states that lower back pain is the single largest cause of lost working days in the working world, costing $60 billion annually in the US.

“If we can get people back to work – as we have demonstrated and as well as we anticipate – not only will we have a wonderful market for ourselves, potentially in the billions, but we will be able to save society much more than that,” he said.

The funding round, which was oversubscribed, was led by Dublin-based Fountain, a new investor for the company. Other new investors include medical device giant Medtronic, Capricorn Venture Partners from Belgium and Seventure Partners, based in France.

French group Sofinnova Partners and US-based Twin City Angels, which have previously put about $6 million into Mainstay, also took part in the latest round.

Manus Rogan, managing partner at Fountain, who is joining the Mainstay board, described the fundraising as a “headturning deal” for a very promising venture. “This is a multibillion dollar market that is poorly served both by drugs – existing and even in the development pipeline – and medical devices,” he said.

Mr Crosby says the company’s proprietary products are based on recent science that attributes the continuing back pain in patients to the “control system for spine stability being out of whack”.

Mainstay is currently sourcing office space in Dublin and will relocate its executive team here.