CAMBRIDGE, MA — April 12, 2005
Momenta Pharmaceuticals, Inc. (Nasdaq: MNTA), a biotechnology company developing drugs based on its proprietary sugar sequencing technology, announced senior management promotions. Ganesh Venkataraman, Ph.D., has been promoted to Senior Vice President, Research, and Steven B. Brugger has been promoted to Senior Vice President, Strategic Business Operations.

“The promotions of Ganesh and Steve are a reflection of the significant leadership that each has brought to Momenta as we have made rapid progress over the past several years,” said Alan Crane, Chairman and Chief Executive Officer of Momenta. “As we continue to grow and evolve, we want to put individuals in positions to achieve their full potential and lead us to greater accomplishments in the future.”

Dr. Venkataraman, as Senior Vice President, Research, will now have a broader leadership position with responsibility for advancing the application of the company’s characterization technology to the development of additional near-term product opportunities and to its discovery pipeline. “Ganesh has displayed significant leadership through his ability to translate a technology developed in academia into a dynamic platform for development of multiple major commercial products,” commented Mr. Crane.

Mr. Brugger, in his new position as Senior Vice President, Strategic Business Operations, will now assume a broader strategic and operational role in the company. As part of his new responsibilities, he will take a senior leadership role on the company’s management team and will oversee the human resources department, in addition to maintaining responsibility for strategic product development. “For the past several years, Steve has been primarily focused on and responsible for building both program and portfolio management capabilities for our company, and leading the progress of our generic enoxaparin program. Through this promotion, we will now leverage his leadership on behalf of the entire Momenta organization,” continued Mr. Crane.

About Momenta:
Momenta Pharmaceuticals, Inc. is a biotechnology company specializing in the detailed structural analysis and design of complex sugars for the development of improved versions of existing drugs, the development of novel drugs and the discovery of new biological processes. Momenta is also utilizing its ability to sequence sugars to create technology-enabled generic versions of sugar-based and biologic drug products. The Company’s most advanced product candidate is M-Enoxaparin, a technology-enabled generic version of Lovenox®. Based on its understanding of complex sugars, Momenta has created a diversified pipeline of near-term product opportunities, novel development products and discovery candidates. Momenta was founded in 2001 and is headquartered in Cambridge, MA.

To receive additional information about Momenta, please visit our website at www.momentapharma.com, which does not form a part of this press release.

Forward Looking Statements:
Statements in this press release regarding Momenta Pharmaceuticals Inc.’s future expectations, beliefs, goals, plans or prospects constitute forward-looking statements within the meaning of the Private Securities Litigation Reform Act of 1995. Momenta’s actual results could differ materially from those stated or implied in forward-looking statements due to a number of factors, including those factors contained in Momenta’s Annual Report on Form 10-K for the year ended December 31, 2004 filed with the Securities and Exchange Commission under the section “Risk Factors that May Affect Results,” as well as other documents that may be filed by Momenta from time to time with the Securities and Exchange Commission. Forward-looking statements include statements regarding Momenta’s expectations, beliefs, intentions or strategies regarding the future and can be identified by forward-looking words such as “anticipate”, “believe”, “could”, “estimate”, “expect”, “intend”, “may”, “should”, “will”, and “would” or similar words. Momenta assumes no obligations to update the information included in this press release.

Our logo, trademarks, and service marks are the property of Momenta Pharmaceuticals, Inc. All other trade names, trademarks, or service marks are property of their respective owners and are not the property of Momenta Pharmaceuticals, Inc.

Contact:
Michael A. Lawless
Momenta Pharmaceuticals, Inc.
617-395-5189

Press Contact
press@momentapharma.com

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