Alnylam Appoints Sara Nochur, Ph.D., as Vice President, Regulatory Affairs.

CAMBRIDGE, Mass. -- Alnylam Pharmaceuticals, Inc. (Nasdaq: ALNY), a leading RNAi therapeutics company, announced today the appointment of Saraswathy (Sara) Nochur, Ph.D., to the position of Vice President, Regulatory Affairs. Dr. Nochur has extensive industry experience in the areas of regulatory affairs and overall drug development. At Alnylam, she will be responsible for leading the global regulatory strategy for the company's development-stage programs and overseeing regulatory operations, and will be a member of the management team.

"Sara is an outstanding addition to the Alnylam team," said John Maraganore, Ph.D., President and Chief Executive Officer of Alnylam Pharmaceuticals. "Her extensive product development and regulatory experience will be an important asset to us as we continue to advance our pipeline of novel RNAi therapeutics through the clinical and regulatory pathways. I look forward to her contributions to our valuable scientific interactions with the regulatory authorities, particularly as she helps to guide the regulatory process of our clinical stage program, ALN-RSV01 for the treatment of respiratory syncytial virus."

Dr. Nochur has over 15 years of experience in the areas of product development and regulatory affairs. Most recently, she held the position of Vice President, Regulatory Affairs at The Medicines Company. Prior to her four years there, she served as Director, Product Development and Regulatory Affairs for CereMedix, Inc. Dr. Nochur also held senior positions at BioTrack, Inc. including Vice President, Product Development and Regulatory Affairs, and Chief Operating Officer. Prior to that she was employed by DynaGen, Inc. where she held positions of increasing responsibility, culminating in the role of Director, New Product Development. Dr. Nochur received her B.S. and M.S. degrees in Microbiology from the University of Bombay in India, and her Ph.D. in Biochemical Engineering at the Massachusetts Institute of Technology.

"The breakthrough field of RNAi therapeutics represents a unique opportunity to develop and bring to market novel drugs that have the potential to treat human disease in an entirely new way," said Dr. Nochur. "I am thrilled to join Alnylam at this important stage as we advance our pipeline of novel therapies into the clinic."

About RNA Interference (RNAi)

RNA interference, or RNAi, is a naturally occurring mechanism within cells for selectively silencing and regulating specific genes. Since many diseases are caused by the inappropriate activity of specific genes, the ability to silence genes selectively through RNAi could provide a new way to treat a wide range of human diseases. RNAi is induced by small, double-stranded RNA molecules. One method to activate RNAi is with chemically synthesized small interfering RNAs, or siRNAs, which are double-stranded RNAs that are targeted to a specific disease-associated gene. The siRNA molecules are used by the natural RNAi machinery in cells to cause highly targeted gene silencing.

About Alnylam

Alnylam is a biopharmaceutical company developing novel therapeutics based on RNA interference, or RNAi. The company is applying its therapeutic expertise in RNAi to address significant medical needs, many of which cannot effectively be addressed with small molecules or antibodies, the current major classes of drugs. Alnylam is building a pipeline of RNAi therapeutics; its lead program is in Phase 1 human clinical trials for the treatment of respiratory syncytial virus (RSV) infection, which is the leading cause of hospitalization in infants in the U.S. The company's leadership position in fundamental patents, technology, and know-how relating to RNAi has enabled it to form major alliances with leading companies including Merck, Medtronic, and Novartis. The company, founded in 2002, maintains global headquarters in Cambridge, Massachusetts, and has an additional operating unit in Kulmbach, Germany. Alnylam is honored to be the "emerging/mid-cap" company recipient of the 2006 James D. Watson Helix Award, the biotechnology industry's award for outstanding achievement. For more information, visit www.alnylam.com.

Alnylam Forward-Looking Statements

Various statements in this release concerning our future expectations, plans, and prospects, including statements with respect to clinical development plans for ALN-RSV01 and our other product candidates and the potential for ALN-RSV01 to be a treatment option for RSV infection patients, constitute forward-looking statements for the purposes of the safe harbor provisions under The Private Securities Litigation Reform Act of 1995. Actual results may differ materially from those indicated by these forward-looking statements as a result of various important factors, including risks related to: our approach to discover and develop novel drugs, which is unproven and may never lead to marketable products; obtaining, maintaining and protecting intellectual property utilized by our products; our ability to enforce our patents against infringers and to defend our patent portfolio against challenges from third parties; our ability to obtain additional funding to support our business activities; our dependence on third parties for development, manufacture, marketing, sales, and distribution of products; the successful development of our product candidates, all of which are in early stages of development; obtaining regulatory approval for products; competition from others using technology similar to ours and others developing products for similar uses; our dependence on collaborators; and our short operating history; as well as those risks more fully discussed in the "Risk Factors" section of our most recent report on Form 10-Q on file with the Securities and Exchange Commission. In addition, any forward-looking statements represent our views only as of today and should not be relied upon as representing our views as of any subsequent date. We do not assume any obligation to update any forward-looking statements.