Leo Cancer Care Closes $65M Series D for Upright Proton Therapy

Leo Cancer Care closed an oversubscribed $65 million Series D financing, the company said Wednesday. Yu Galaxy led the round, with Eventide Asset Management joining as a new investor. Existing backers also participated.

The Middleton, Wisconsin-based medical technology company builds systems that treat cancer patients in an upright, seated position. Its first product, Marie, is a CT scanner and patient positioning system for proton therapy. Instead of rotating a heavy gantry around the patient, Marie rotates the patient. That cuts the size, cost, and complexity of proton therapy equipment, the company said.

The oversubscribed round signals investor appetite for technologies that could lower the barriers to proton therapy. The treatment is more precise than conventional radiation but remains expensive and limited to large hospital centers. Leo Cancer Care’s approach could make it feasible for smaller clinics and more accessible to patients globally.

Proceeds from the Series D will support commercialization of Marie and expansion into new markets, the company said. The system is designed to work with existing proton therapy machines, which could speed adoption without requiring facilities to replace their entire infrastructure.

Leo Cancer Care has not disclosed its valuation or revenue figures. The company is privately held.