$15 Million Committed to Seattle-based Accelerator Corporation
Unique Collaboration of Four Life Science Leaders and Non-Profit Research Institute Catalyze Biotech Start-Ups

Seattle, WA, May 22, 2003 – With $15 million in committed capital from a financing led by MPM Capital with ARCH Venture Partners, Versant Ventures, and Alexandria Real Estate Equities, Inc. (NYSE: ARE), the four life science leaders and the Institute for Systems Biology (ISB) today announced the formation of Accelerator Corporation, a collaborative partnership that will reduce to practice the leading scientific ideas in systems biology and other related areas. Accelerator is a first-of-its-kind collaboration, bringing together three leading venture capital firms (MPM, ARCH, and Versant) with the premier real estate operating company principally focused on the life science sector (Alexandria) and a world-renowned non-profit research institute (ISB) to better position biotechnologies and early-stage companies for success from their outset. Together these groups will provide the capital, expertise and experience required to enable Accelerator to identify, finance and develop leading edge ideas and technologies that either emerge from ISB or, if developed elsewhere, would benefit from affiliation with the ISB’s faculty, staff, infrastructure and core facilities.

Accelerator Corporation will leverage the pre-eminent faculty of the ISB, including Leroy Hood, MD, Ph.D., President of the ISB; the long track record for building successful companies of MPM, ARCH, and Versant; and the unique and industry-leading competency of Alexandria in the design and development of state-of-the-art laboratory space. The world-class resources and particular core competencies of these organizations will be combined at Accelerator to identify and develop the most exciting and powerful emerging biotechnology ideas and technologies. Accelerator will provide the management, infrastructure, and facilities required by these start-up ventures, enabling their scientific founders to focus on achieving key short-term research, development, and commercialization milestones. Upon achievement of these milestones, Accelerator will prepare the ventures to raise their next rounds of financing, facilitating their transition from exciting leading-edge technology stage companies into fully integrated biotechnology companies.

Dr. Hood, who is a member of the Board of Directors of Accelerator Corporation, said, “One of the key missions of ISB is to enable the development of products and technologies which will fundamentally revolutionize medicine. Accelerator represents an innovative vehicle for the achievement of this vision, whether through the commercialization of ISB-generated technologies or through the enablement, with our affiliation, of technologies originating elsewhere.”

Michael Steinmetz, MD, Ph.D., General Partner of MPM Capital L.P. and member of Accelerator’s Board of Directors said, “This completely unique effort brings together virtually all of the key assets required to move nascent technologies from idea to commercializable product. The affiliation with ISB and Lee Hood, with whom MPM has a long-standing and valuable relationship, is critical to the success of this venture.”

Bob Nelsen, Managing Director of ARCH Venture Partners and a member of the Accelerator Board of Directors, said, “Accelerator is a completely unique and fresh approach to biotech company formation. It combines many of the lessons our three firms have learned with a return to technology investing - the roots of venture capital. The result is that we have put together a top-flight group in which all of the constituents are willing and ready to roll-up our sleeves and do our parts to build exciting companies that would not have been created otherwise.”

ABOUT the Institute for Systems Biology
The Institute for Systems Biology (ISB) is an internationally renowned non-profit research institute dedicated to the study and application of systems biology. ISB's goal is to unravel the mysteries of human biology and identify strategies for predicting and preventing diseases such as cancer, arthritis and AIDS. The driving force behind the innovative "systems" approach is the integration of biology, computation, and technology. This approach allows scientists to analyze all of the elements in a system rather than one gene or protein at a time. Located in Seattle, Washington, the Institute has grown to eight faculty and more than 170 staff members; has been awarded almost $130 million in funding; and has an extensive network of academic and industrial partners. For more information, contact: www.systemsbiology.org.

ABOUT MPM Capital
MPM Capital L.P. is a global investment management firm focused solely on life sciences investing. One of the largest investment management firms dedicated to the life sciences sector, MPM Capital has offices in Boston, San Francisco, and Munich. MPM’s portfolio includes early stage start-ups as well as large capitalization public companies, representing biopharmaceutical and medical device companies, encompassing platform technology as well as product-driven opportunities. The firm manages over $2.1 billion in assets through the MPM BioVentures Family of venture capital funds and the MPM BioEquities public market funds.

ABOUT ARCH Venture Partners
With offices in Seattle, Albuquerque, Austin, Chicago, and New York, ARCH Venture Partners is a premier provider of seed and early stage venture capital for the commercialization of innovations in life sciences, the physical sciences and information technology. Partnering with entrepreneurs, academic institutions and national research laboratories nationwide, ARCH has built more than 100 successful companies, many of them from the concept stage. ARCH's life science investments include Optobionics Corp., Caliper Technologies, Adolor Corp., DeCode Genetics, Illumina, Inc., Nanosys Inc., Array BioPharma, Inc., Xenoport Inc., Xcyte Therapies, Inc. and GeneCraft among others. ARCH currently has $700M under management.

ABOUT Versant Ventures
Versant Ventures was founded in 1999 by life sciences partners from Brentwood Venture Capital, Crosspoint Venture Partners, and Institutional Venture Partners. The firm has approximately $670 million under management. The firm has 11 investment professionals, with offices in Menlo Park and Newport Beach. Portfolio companies from the firm's initial fund include Amphora, FivePrime, Genomic Health, Pharmion, and Syrrx.

ABOUT Alexandria Real Estate Equities, Inc.
Alexandria Real Estate Equities, Inc. is the first and only publicly traded real estate operating company focused principally on the ownership, operation, management, acquisition, expansion and selective redevelopment and development of properties containing office/laboratory space. Alexandria is the Landlord of Choice to the Life Science IndustrySM, providing high-quality office/laboratory space and services to the broad and diverse life science sector. Alexandria's national operating platform is based on the principle of "clustering", with assets and operations strategically located in key life science hub markets.