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Learn More About Proton Therapy

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Still River Systems becomes Mevion Medical Systems

Move signals the company’s transition from Research and Development to Product Commercialization.

Littleton, Mass. -- Mevion Medical Systems, Inc. announced today that it changed its name from Still River Systems. This change reflects the company’s transition from a research and development organization to the commercial manufacturer of the MEVION S250™ Proton Therapy System.

Proton therapy is widely regarded as the optimal means of delivering therapeutic radiation to treat a variety of cancers, but is not widely available because of the immense size, enormous expense, and sheer complexity of traditional proton therapy systems. Mevion eliminates these obstacles with the introduction of the MEVION S250, a revolutionary proton therapy system that combines a patented, gantry-mounted proton source with highly integrated, image-based workflow – making proton therapy a practical clinical reality. “Years of intense and focused research lead to the development of a breakthrough high-energy proton source, the world’s first superconducting synchrocyclotron”, says Dr. Kenneth Gall, Co-Founder and Chief Technology Officer. “This innovative design allowed us to dramatically reduce the size, cost and complexity of proton acceleration, while preserving all of the treatment benefits of proton therapy.”

"Since our inception, we have been dedicated to developing a safe, precise and efficient approach to proton therapy. Similar in footprint, workflow, and throughput to a modern radiation therapy linac, the MEVION S250 provides a remarkably practical means of delivering cutting-edge cancer care”, said Joseph Jachinowski, Chief Executive Officer of Mevion Medical Systems. “Today we feel confident that we can expand our focus from strictly R&D to full product commercialization. Given this important moment in our history, we think it is appropriate that we mark this transformation with a new name and identity”.

The MEVION S250 was introduced with the new corporate branding at the 2011 Annual Meeting of the American Society of Radiation Oncology (ASTRO) in Miami Beach, Fl; October 2nd – 4th at the Miami Beach Convention Center. Full details of Mevion’s technology and the MEVION S250 Proton Therapy System can be found on the new corporate website,

About Mevion Medical Systems

Mevion Medical Systems, Inc. (formerly Still River Systems, Inc.) is a radiation therapy company dedicated to advancing the treatment of cancer. As the pioneering developer of modern proton therapy systems, Mevion provides innovative, safe, and effective solutions by transforming advances in medical technology and science into practical clinical reality.

Mevion’s flagship product, the MEVION S250 Proton Therapy System, is designed to preserve all of the treatment benefits of traditional proton therapy systems while removing the obstacles of size, cost, and complexity. Realizing this vision, Mevion has forever changed the economics and accessibility of proton therapy worldwide.

Founded in 2004, Mevion is a privately held company headquartered in the Boston metropolitan area with international offices in the United Kingdom and Japan.

The MEVION S250 Proton Therapy Systems is USFDA 510(k) cleared and complies with all MDD / CE requirements.

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