CAMBRIDGE, Mass.--(BUSINESS WIRE)--Nov. 15, 2005--Alnylam Pharmaceuticals, Inc. (Nasdaq: ALNY), a leading RNAi therapeutics company, announced today that it presented pre-clinical data at the 35th Annual Society for Neuroscience Meeting being held in Washington, D.C. from November 12-16, 2005. Alnylam and its academic collaborators presented data from three ongoing neurology programs focused on Parkinson's disease, Huntington's disease, and neuropathic pain.

"Data emerging from the neuroscience community continues to point to the potential of RNAi therapeutics for the treatment of neurological diseases," said Victor Kotelianski, M.D., Ph.D., Vice President of Research at Alnylam Pharmaceuticals. "Results from our ongoing pre-clinical studies support the strategy of using siRNAs to treat these diseases. We are excited about the data presented at the Society for Neuroscience meeting, which we believe support an RNAi approach for neurological diseases and demonstrate the progress that Alnylam continues to make in this area."

Parkinson's Disease
Alnylam has designed and synthesized siRNAs that are specific to the alpha-synuclein gene, a gene associated with Parkinson's disease. The siRNAs are stable in cerebrospinal fluid, and potently silence the alpha-synuclein gene in neurons in vitro. In collaboration with Dr. Matthew Farrer and Dr. Jada Lewis at Mayo Clinic, these siRNAs are now being tested in animal models to examine alpha-synuclein silencing in vivo. Preliminary data show that the siRNAs are taken up by central nervous system neurons in vivo and can be transported to brain regions distant from the site of injection, which could be beneficial for the treatment of Parkinson's disease.

Huntington's Disease
In collaboration with the laboratory of Dr. Neil Aronin, Alnylam scientists applied proprietary technology to siRNAs identified by Dr. Aronin and Dr. Philip Zamore, both of the University of Massachusetts Medical School, that silence huntingtin, the gene that is mutated in Huntington's disease. In this pre-clinical study, the siRNAs administered into the brain were taken up by the same type of neurons that are most affected in the early stages of Huntington's disease. Ongoing studies are examining the effect these siRNAs have in inhibiting the disease process in animal models of Huntington's disease.

Neuropathic Pain

Neuropathic pain is chronic pain associated with damage to the nervous system and can be attributable to a range of causes including lower back injury, diabetic neuropathy, cancer treatment, and shingles. Data were presented demonstrating that siRNAs can be used to silence targets associated with neuropathic pain, potentially providing pain relief. In the first pre-clinical studies, the laboratories of Dr. Frank Porreca and Dr. Josephine Lai at the University of Arizona evaluated siRNAs that target the gene for NPY, a pain-associated peptide. The set of siRNAs were designed at the University of Arizona and Alnylam with modifications using proprietary technology at Alnylam. An siRNA was then administered by intrathecal injection, and over the course of treatment, results showed significant pain relief.

In a second study, siRNAs were designed by Alnylam to target a gene, NaV1.8, which encodes an ion channel. NaV1.8 is recognized to play a significant role in chronic neuropathic pain, but has proved extremely difficult to inhibit selectively with traditional small molecule drugs. The pre-clinical data demonstrated that siRNAs targeting NaV1.8 administered by intrathecal injection can provide nearly complete pain relief.

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 a breakthrough in biology known as RNA interference, or RNAi. The company, founded in 2002 by scientific pioneers in the field of RNAi, maintains a leadership position in fundamental patents, technology, and know-how relating to RNAi. Alnylam is applying its expertise in RNAi to address multiple therapeutic opportunities that cannot effectively be addressed with small molecules or antibodies, the two current major classes of drugs. The company's expertise in designing and optimizing RNAi therapeutics has enabled Alnylam to form major alliances with leading companies including Merck, Medtronic, and Novartis. The company's global headquarters are in Cambridge, Massachusetts, with an additional operating unit in Kulmbach, Germany. For more information, please visit www.alnylam.com.

Alnylam Forward-Looking Statements
Various statements in this release concerning our future expectations, plans and prospects, including our views with respect to the potential of using siRNAs to treat neurological diseases, 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; our ability to obtain additional funding to support our business activities; our dependence on third parties for development, manufacture, marketing, sales and distribution of our products; the successful development of products, 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; obtaining, maintaining and protecting intellectual property utilized by our products; our dependence on collaborators; and our short operating history; as well as those risks more fully discussed in the "Certain Factors That May Affect Future Results" section of our most recent quarterly 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.

SOURCE: Alnylam Pharmaceuticals, Inc.

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