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Learn More About Proton Therapy
Learn More About Proton Therapy

About Mevion

Mevion Medical Systems exists to deliver on the promise of proton therapy for cancer centers, clinicians and patients worldwide. We invented compact proton therapy and are continuing to transform the industry and patient care with the MEVION S250 Series™.

As a testament to the proven results delivered by our systems, we have more systems installed and treating patients than any other compact proton therapy manufacturer.

Powerful Medicine. Smart Business.

The MEVION S250 Series integrates our patented technology at the very forefront of proton therapy to deliver exceptional beam quality, industry-leading uptime, reduced system size and complexity, higher reliability and throughput, and lower capital and operating costs. Because of these advantages, more NCI-Designated Cancer Centers choose Mevion than any other proton therapy system provider.

The Mevion advantage is clear:

  • Superior clinical performance
  • Highly efficient design
  • Lower cost and rapid deployment
  • Proven profitability

Leadership Team

  • Lawrence Yuan Tian, Ph.D.


    Lawrence Yuan Tian, Ph.D.


    Mevion has benefited from Dr. Lawrence Tian’s leadership as a member of the board of directors since 2015 and was appointed Chairman in 2018. Dr. Tian brings a wealth of experience from the life sciences and medical device industry to this role. He is a Founding Partner of YuanMing Capital, a leading private equity firm which focuses on the investment in pharmaceutical research and development, innovative medical devices and high-end medical services in both China and the United States. He also serves as the Chairman of Investment Committee of China Pharmaceutical Industry Research and Development Association, and he is a member of the Biotech Advisory Panel of the Stock Exchange of Hong Kong Limited.

    Dr. Tian also brings experience networking business leaders to the Mevion leadership team. He is the founder and Chairman of the China Entrepreneurs Forum, the most influential business owners association in China, and is the founder of the China-U.S. Business Leaders Roundtable, a prestigious cross-border communication platform.

    Prior to Mevion, Dr. Tian has had successful career as a serial entrepreneur with a strong track record of success. In the financial markets, he founded China International Futures Co., Ltd. (CIFCO) in 1992. CIFCO grew into a leading brokerage firm and achieved the largest market share in China during his chairmanship. He also co-founded Wumart Group in 1994, which is currently the largest supermarket chain in Northern China.

    Dr. Tian obtained his master’s degree and doctoral degree from Wuhan University. He received the China Economics Theory Innovation Award, China’s highest prize for economics. 

  • Joseph K. Jachinowski

    Executive Director

    Joseph K. Jachinowski

    Executive Director

    With more than thirty years of experience in the field of oncology, Joe brings an unmatched depth of expertise and experience to our company. He served as Mevion’s chief executive officer and president from 2009 to 2018. Since joining the company, Joe oversaw the development of industry-leading technologies and our growth into a leading global provider of proton therapy systems.

    Joe cofounded IMPAC Medical Systems and served as its president and chief executive officer from 1990 through the company’s initial public offering and sale to Elekta in 2005. After the sale, Joe was an executive vice president of Elekta for four years running global R&D and North American commercial operations. Joe began his career at Varian Medical Systems, Inc., where he led the team that developed linear accelerators from 1983 to 1990.

    He holds a Bachelor of Science from Ohio University and Master of Science from Washington State University.

  • Tina Tianning Yu, Ph.D.

    Chief Executive Officer

    Tina Tianning Yu, Ph.D.

    Chief Executive Officer

    Mevion’s Chief Executive Officer, Dr. Tina Yu, brings more than fifteen years of professional experience working in the life sciences sector and the financing world of the healthcare industry. As a Managing Partner of YuanMing Capital, a healthcare fund focusing on cross-border investment strategies, Dr. Yu led the investment in BeiGene, Ascentage Pharmaceuticals, and Mevion Medical Systems. Prior to that, Dr. Yu worked for Vision Capital, a NYC-based investment management firm, as a Director of Investment, responsible for US biotech and China sectors. Before becoming an investor, Dr. Yu was a senior research scientist at Wyeth BioPharma, where she specialized in therapeutic protein development. She also worked for Fidelity, Morgan Stanley and Genzyme. Dr. Yu founded Matching Capital Partners to provide cross-border consulting services in the life sciences industry.

    Dr. Yu holds a PhD in Chemistry from Princeton University, an MBA from Harvard Business School, and a B.S. in Biology from University of Science and Technology of China.