Archemix IS GRANTED Two european patents for the identification and use of therapeutic aptamers

CAMBRIDGE, MA – March 8, 2007 – Archemix Corp., the leading aptamer therapeutics company, announced today the issuance of two key, broad patents by the European Patent Office (“EPO”). The patents, EP 0 786 469 and EP 0 668 931, broadly cover methods for the identification and use of aptamers for therapeutic applications. These claims are the foundation for the fundamental methods of selecting aptamer therapeutics using the SELEX platform. Diagnostic claims were also allowed in this action. The diagnostic rights are owned by Archemix collaborator SomaLogic, a company developing aptamers for diagnostic applications and instrument platforms (see www.somalogic.com).

Specifically, EP 0 668 931 includes claims that cover methods for identifying aptamers with improved characteristics such as decreased size, improved stability, improved target binding, resistance to clearance, the capability to cross tissue or cell membrane barriers, or the ability to modify the biological activity of the target.

EP 0 786 469 includes claims that cover the use of aptamers in the manufacture of a therapeutic agent. Specific uses of therapeutic aptamers covered by EP 0 786 469 include uses wherein the aptamer modifies, e.g., inhibits or activates, a function of the target molecule, affects the catalytic activity of enzymes, affects the functionality of protein receptors, affects the formation of protein multimers, inhibits binding to receptors, modifies the specificity of binding to receptors, modifies hormone action, modifies the transport properties of proteins, or acts as a drug delivery vehicle.

“We are gratified that the EPO has acknowledged the broad applicability of aptamers as therapeutic agents. The allowance of these new claims in the world's second largest pharmaceutical market further extends the robust and far-reaching position Archemix has established in intellectual property required for the discovery, development and commercialization of aptamer therapeutics,” said Dr. Errol De Souza, President and Chief Executive Officer of Archemix. “Our intellectual property estate continues to yield issued patents solidifying our broad rights relating to the discovery, development, and commercialization of aptamer-based therapeutics. The strength of our patent estate supports a track record of business execution with nine current partners and licensees including four major partnerships consummated over the past eight months.”

About Aptamers

Aptamers are single-stranded nucleic acids that form well-defined three dimensional shapes, allowing them to bind target molecules in a manner that is conceptually similar to antibodies. Aptamers combine the optimal characteristics of small molecules and antibodies, including high specificity and affinity, chemical stability, low immunogenicity, and the ability to target protein-protein interactions. In contrast to monoclonal antibodies, aptamers are chemically synthesized rather than biologically expressed, offering a significant cost advantage.

About Archemix Corp.

Archemix Corp. is a privately-held biopharmaceutical company based in Cambridge, Massachusetts. The company's mission is to develop aptamers as a class of directed therapeutics for the prevention and treatment of human disease. Because of their unique properties and proven efficacy, aptamers offer an alternative to biologics and small molecules in numerous applications and offer the potential to be a major class of drugs for the treatment of unmet medical needs.

Archemix's aptamer expertise is complemented by a robust patent estate comprised of over 220 issued and 230 pending patents covering the identification, composition, and use of therapeutic aptamers. In addition to the company's core aptamer generation technology, Archemix possesses strong expertise in both pre-clinical and clinical drug development. Further information on Archemix can be found at www.archemix.com.

For further information about Archemix or aptamers, or to speak with Dr. Errol De Souza, please contact Davia Temin or Suzanne Oaks of Temin and Company at 212-588-8788 or news@teminandco.com.

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