Boston Scientific bought a 34% equity stake in private medtech MiRus for $1.5 billion, and it’s not done. The deal includes an exclusive option to take 100% ownership of MiRus’s SIEGEL Balloon Expandable TAVR system for an additional $3 billion in cash, bringing the total potential outlay to $4.5 billion.
MiRus is a private company, so there’s no per-share premium to calculate. But $1.5 billion for a 34% stake implies a company valuation around $4.4 billion on the equity alone. The $3 billion TAVR option would be layered on top, contingent on additional payments and milestone achievements.
What does Boston Scientific actually get? The SIEGEL system’s delivery sheath is designed to be roughly half the size of those currently on the market, which could reduce vascular injury risk. The device is investigational: it hasn’t cleared FDA yet, and peak-sales projections weren’t disclosed. Compare that to Boston Scientific’s $14.5 billion Penumbra deal earlier this year, where it bought a commercial-stage thrombectomy portfolio. This one’s a bet on a pipeline.
The timing matters. Boston Scientific pulled its own TAVR platforms, Acurate neo2 and its successor Acurate Prime, from global markets last year after clinical study setbacks. It also walked away from U.S. approval efforts. The MiRus deal fills that gap, assuming SIEGEL clears the regulatory bar the Acurate platform couldn’t.
No close date was disclosed. The real question: does Boston Scientific take up the $3 billion option when the time comes, or does this stay a 34% bet?
Diana Kowalski