Merck & Co., Inc. to Acquire GlycoFi, Inc.; Acquisition Enhances Merck Capabilities in Biologics Research and Development

Glycoengineering provides the ability to make proteins such asmonoclonal antibodies with pre-specified and defined humancarbohydrate side chains. The ability to make such proteins in yeasthas advantages of speed, cost and quality over current methods ofproducing monoclonal antibodies and other protein therapeutic agents.

Under the terms of the merger agreement, Merck will acquire 100percent of the equity of GlycoFi, which will become a wholly-ownedsubsidiary of Merck & Co, Inc. The all-cash transaction is valued atapproximately $400 million and is expected to close in the secondquarter of 2006, subject to customary closing conditions and clearanceunder the Hart-Scott-Rodino Anti-Trust Improvements Act.

"Our acquisition of GlycoFi's scientific expertise, patent estateand robust technology platform is a significant step toward enablingMerck to discover, optimize and develop novel biologic drugs to servethe needs of patients worldwide," said Peter S. Kim, Ph.D., president,Merck Research Laboratories. "GlycoFi's technology also complementsour own industry-leading capabilities in yeast expression technology,as shown by the production of the virus-like particles in GARDASIL(R),our investigational human papillomavirus vaccine. Further, GlycoFi'stechnology combined with Merck's yeast expression capabilities couldlead to a more effective platform for the manufacture of therapeuticproteins and vaccines."

GlycoFi, which was founded in 2000, is based in Lebanon, N.H. andhas about 55 employees. GlycoFi boasts a novel, yeast-based,proprietary protein optimization technology that has the potential foruse in developing, producing and commercializing novelbiotherapeutics.

This scientifically groundbreaking technology could significantlyenhance the ability of Merck scientists to discover, develop andproduce novel drugs in many therapeutic areas, such as oncology, aswell as novel vaccines for infectious diseases. Oncology and novelvaccines are two of nine priority disease areas of research for Merck.The speed and efficiency of the process will also enable rapidproduction of monoclonal antibodies for testing novel mechanisms forproof of concept, thus enhancing overall probability of success fordevelopment programs in many disease areas.

Merck and GlycoFi have been partners since late 2005, when theyestablished a strategic alliance and research collaboration to developnovel biologic and vaccine candidates. It was on the basis of thatcollaboration and Dr. Kim's identification of the need to increasebiologic research and development capabilities that led Merck toacquire GlycoFi, according to Merv Turner, Ph.D., senior vicepresident, Worldwide Licensing and External Research.

"Our successful partnership with GlycoFi helped fuel our interestin expanding our commitment and capabilities in the biologics field,"Dr. Turner said. "GlycoFi and Merck are a natural match, given Merck'sexpertise in yeast expression, coupled with GlycoFi's noveltechnologies. This agreement is one more example of our bringinggroundbreaking science from a biotechnology partner into Merck."

Terry McGuire, managing partner, Polaris Venture Partners andGlycoFi's founding investor, agreed. "Merck's commitment to biologicsand deep discovery and development expertise make it an ideal partnerfor GlycoFi," he said.

GlycoFi chief scientific officer and co-founder Tillman Gerngross,Ph.D., added that "based on the work we have done together, and theimpressive scientific talent in both organizations, we are confidentthat the full value of GlycoFi's technology will be realized byMerck."

Richard N. Kender, vice president of Business Development andCorporate Licensing at Merck, described the acquisition of GlycoFi as"a first step in executing on Merck's strategic objectives byacquiring a biotechnology company that complements the Company'spipeline and internal research capabilities."

About Merck

Merck & Co., Inc. is a global research-driven pharmaceuticalcompany dedicated to putting patients first. Established in 1891,Merck currently discovers, develops, manufactures and markets vaccinesand medicines to address unmet medical needs. The Company devotesextensive efforts to increase access to medicines through far-reachingprograms that not only donate Merck medicines but help deliver them tothe people who need them. Merck also publishes unbiased healthinformation as a not-for-profit service. For more information, visitwww.merck.com.

About GlycoFi

GlycoFi is a private, venture-backed, biotechnology company whoseinvestors include Polaris Venture Partners, SV Life Sciences, BostonMillennia Partners, and Fletcher Spaght Ventures. GlycoFi leveragesits pioneering protein optimization technology to develop, produce andcommercialize Next Generation Biotherapeutics(TM), alone and inpartnership with other leading biopharmaceutical companies. Foradditional information, visit www.glycofi.com.

Merck Forward-Looking Statement

This press release contains "forward-looking statements" as thatterm is defined in the Private Securities Litigation Reform Act of1995. These statements are based on management's current expectationsand involve risks and uncertainties, which may cause results to differmaterially from those set forth in the statements. The forward-lookingstatements may include statements regarding product development,product potential or financial performance. No forward-lookingstatement can be guaranteed, and actual results may differ materiallyfrom those projected. Merck undertakes no obligation to publiclyupdate any forward-looking statement, whether as a result of newinformation, future events, or otherwise. Forward-looking statementsin this press release should be evaluated together with the manyuncertainties that affect Merck's business, particularly thosementioned in the cautionary statements in Item 1 of Merck's Form 10-Kfor the year ended Dec. 31, 2005, and in its periodic reports on Form10-Q and Form 8-K, which the Company incorporates by reference.