CAMBRIDGE, MA — September 22, 2005 – Momenta Pharmaceuticals, Inc. (Nasdaq: MNTA), a biotechnology company developing drugs based on its proprietary sugar sequencing technology, announced today that Alan L. Crane, President and Chief Executive Officer, will present at the UBS Life Sciences Conference on Tuesday, September 27, 2005 at 4:30 pm EDT at the Grand Hyatt Hotel in New York, NY. A live audio webcast of the presentation will be available on the “Investors” section of the Company’s website located at www.momentapharma.com. A replay of the presentation will be posted on the Momenta website approximately thirty minutes after the event and will be available through October 29, 2005.

About Momenta:
Momenta Pharmaceuticals, Inc. is a biotechnology company specializing in the detailed structural analysis and design of complex sugars for the development of novel drugs, the improvement of existing drugs and the discovery of new biological processes. Momenta is also utilizing its ability to sequence sugars to create technology-enabled generic versions of complex 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.

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.

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

Press Contact
press@momentapharma.com

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