Boston Scientific announced a $1.5B strategic investment in MiRus on May 18, 2026. The payment buys an equity stake of about 34%. It also gives Boston Scientific an exclusive option to acquire the rest of MiRus's transcatheter aortic valve business. That would cost up to $3B more, paid against clinical and regulatory milestones. MiRus keeps a right to further payments on SIEGEL valve net sales. Boston Scientific also holds a separate option on the company's mitral and tricuspid assets.
SIEGEL is a nickel-free, balloon-expandable TAVR valve. The frame uses a proprietary rhenium alloy with a nitric oxide coating, and the leaflets are dry porcine tissue. It comes in 23, 26 and 29 mm sizes. It delivers through an 8 French expandable sheath, about half the size of current TAVR sheaths by the company's account. The STAR trial has just started. It will enroll up to 1,025 patients with severe symptomatic aortic stenosis at low, intermediate and high surgical risk.
Founder and CEO Jay Yadav, an interventional cardiologist, built the Marietta, GA company on molybdenum-rhenium alloys already used in its spine implants. openFDA lists 24 510(k) clearances under MiRus, LLC, the latest K253444 on March 18, 2026, for EUROPA posterior cervical fusion navigated instruments. Boston Scientific expects the deal to be immaterial to 2026 adjusted EPS.
Structurally this is a priced option. Boston Scientific pays for a third of the company now and buys the rest only if STAR delivers. For MiRus, $1.5B at the start of its approval trial exceeds what most structural heart startups raise in their lifetime.