Cambridge, MA and Boulder, CO
August 7, 2007

Archemix Corp. and SomaLogic, Inc. announced today an expansion of their alliance focused on the use and development of aptamers for therapeutic, diagnostic, and other applications.

This expanded alliance broadens the companies’ existing relationship by cross-licensing new technologies being developed by the companies and sharing their respective know-how. Under the terms of the expanded agreement, Archemix receives exclusive rights to therapeutic uses of aptamers discovered by SomaLogic for a limited number of targets identified by Archemix. Additionally, Archemix will have the option of providing targets to SomaLogic for the generation of aptamers. SomaLogic will receive rights to all ex vivo uses of aptamers which it did not previously hold, including the use of aptamers for affinity purification. Other provisions of the original cross-license agreement between the two companies remain unchanged. Financial terms were not disclosed.

About Aptamers
Aptamers are synthetically-derived oligonucleotides, or short nucleic acid sequences. Aptamers represent an emerging class of potential therapeutic agents that Archemix believes may have broad application to treat a variety of human diseases. Archemix believes that aptamer therapeutics combine many of the beneficial characteristics of biologics, small molecules and other classes of oligonucleotides, such as antisense and small interfering RNA, or siRNA, without exhibiting many of their disadvantages. Aptamers have the ability to disrupt interactions between proteins, bind with high affinity and specificity to their targets and can be designed to have a specified duration of action.

About Archemix
Archemix is a biotechnology company focused on discovering, developing and commercializing aptamer therapeutics. Using Archemix’s proprietary processes for discovering aptamers, which are protected by its patent portfolio, Archemix is developing aptamer product candidates for cardiovascular and hematological diseases and cancer. Archemix has completed a Phase 1 clinical trial for ARC1779, its lead aptamer product candidate and, subject to regulatory review of its proposed protocol, Archemix expects to commence Phase 2a and Phase 1b clinical trials of ARC1779 in two distinct indications in the fourth quarter of 2007. In addition, Archemix has licensed its intellectual property to third parties to develop their own aptamer product candidates. To date, Archemix has licensed its intellectual property to discover or develop aptamer product candidates to nine biotechnology and pharmaceutical companies, including Pfizer, Merck Serono, Takeda Pharmaceuticals and Elan Pharma. Archemix expects two of these aptamer product candidates being developed by third parties to enter Phase 2 clinical trials in the second half of 2007.

About SomaLogic
SomaLogic is developing proteomics systems and applications based on its proprietary aptamer technology. The company's aptamer arrays will allow researchers--and ultimately clinicians--to measure large numbers of proteins simultaneously, providing the foundation for new insights into disease and health. SomaLogic is headquartered in Boulder, Colorado. Further information about the company can be found at www.somalogic.com.