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CAMBRIDGE, Mass.--([ BUSINESS WIRE ])--[ Alnylam Pharmaceuticals ], Inc. (Nasdaq: ALNY), a leading RNAi therapeutics company, announced today that it will present new data from its ALN-TTR program at the VIIIth International Symposium on Familial Amyloidotic Polyneuropathy being held in Kumamoto, Japan from November 20-22, 2011. This includes data from its blinded, randomized, placebo-controlled, single dose escalation Phase I clinical trial of ALN-TTR01 in patients with transthyretin (TTR)-mediated amyloidosis (ATTR).

"Phase I safety, pharmacokinetic and pharmacodynamics results for ALN-TTR01, a novel RNAi therapeutic for the treatment of transthyretin amyloidosis"

Presentations from Alnylam scientists at the meeting include:

• a presentation titled aQuantitation of wild-type, V30M, and V122I serum TTR protein by an LC-MS/MS method in humans with amyloidogenic mutant TTR variants,a in the Oral presentation 2 session being held on Sunday, November 20 from 12:00 p.m. a" 12:48 p.m. JST (Saturday, November 19 from 10:00 p.m. a" 10:48 p.m. ET); and,
• a presentation titled aPhase I safety, pharmacokinetic and pharmacodynamics results for ALN-TTR01, a novel RNAi therapeutic for the treatment of transthyretin amyloidosis,a during the Development of essential therapy for FAP session being held on Monday, November 21 from 10:25 a.m. a" 12:05 p.m. JST (Sunday, November 20 from 8:25 p.m. a" 10:05 p.m. ET).

Conference Call Information

Alnylam will host a conference call on Monday, November 21 at 8:30 a.m. ET to discuss the Phase I results of its ALN-TTR01 clinical trial. To access the call, please dial 866-783-2146 (domestic) or 857-350-1605 (international) five minutes prior to the start time and provide the passcode 40291676. A replay of the call will be available beginning at 11:30 a.m. ET on November 21, 2011. To access the replay, please dial 888-286-8010 (domestic) or 617-801-6888 (international), and provide the passcode 13561687.

A live audio webcast of the call will also be available on the News & Investors page of the companyas website, [ www.alnylam.com ]. An archived webcast will be available on the Alnylam website approximately two hours after the event.

About Transthyretin-Mediated Amyloidosis

Transthyretin (TTR)-mediated amyloidosis (ATTR) is a hereditary, systemic disease caused by mutations in the TTR gene. TTR protein is produced primarily in the liver and is normally a carrier for thyroid hormones and retinol binding proteins. Mutations in TTR cause abnormal amyloid proteins to accumulate in and damage body organs and tissue such as the peripheral nerves and heart, resulting in intractable peripheral sensory neuropathy, autonomic neuropathy, and/or cardiomyopathy. In its severest form, ATTR represents a major unmet medical need with significant morbidity and mortality as an orphan disease; FAP (familial amyloidotic polyneuropathy) affects approximately 5,000 to 10,000 people worldwide and FAC (familial amyloidotic cardiomyopathy) affects approximately 40,000 people worldwide. ATTR patients with FAP have a mean life expectancy of five to 15 years from symptom onset and the only treatment option is liver transplantation; as a result there is a significant need for novel therapeutics to treat patients who have inherited mutations in the TTR gene.

About ALN-TTR Program

ALN-TTR01 is a systemically delivered RNAi therapeutic being developed for the treatment of transthyretin (TTR)-mediated amyloidosis (ATTR), including familial amyloidotic polyneuropathy (FAP) and familial amyloidotic cardiomyopathy (FAC). Pre-clinical studies have shown that treatment with ALN-TTR01 results in both prevention and regression of pathogenic TTR deposits in peripheral tissues including dorsal root ganglia, sciatic nerve, stomach, and intestines in animal models. In addition, ALN-TTR01 administration in pre-clinical animal models was found to result in dose-dependent and durable, yet reversible silencing of the TTR gene and serum levels of TTR. ALN-TTR01 is currently in a randomized, placebo-controlled, dose escalation Phase I clinical trial. The primary objective of this study is to evaluate the safety and tolerability of a single dose of intravenous ALN-TTR01; secondary objectives include characterization of plasma and urine drug pharmacokinetics and assessment of pharmacodynamic activity based on measurements of circulating TTR serum levels. In parallel, Alnylam is also advancing ALN-TTR02, which utilizes second-generation delivery technology. The ALN-TTR02 program is on track for an investigational new drug (IND) or IND equivalent application filing at or around yearas end 2011. In 2012, following results from both ALN-TTR01 and ALN-TTR02 studies, Alnylam expects to advance this program into Phase II clinical studies.

About RNA Interference (RNAi)

RNAi (RNA interference) is a revolution in biology, representing a breakthrough in understanding how genes are turned on and off in cells, and a completely new approach to drug discovery and development. Its discovery has been heralded as aa major scientific breakthrough that happens once every decade or so,a and represents one of the most promising and rapidly advancing frontiers in biology and drug discovery today which was awarded the 2006 Nobel Prize for Physiology or Medicine. RNAi is a natural process of gene silencing that occurs in organisms ranging from plants to mammals. By harnessing the natural biological process of RNAi occurring in our cells, the creation of a major new class of medicines, known as RNAi therapeutics, is on the horizon. Small interfering RNAs (siRNAs), the molecules that mediate RNAi and comprise Alnylamas RNAi therapeutic platform, target the cause of diseases by potently silencing specific mRNAs, thereby preventing disease-causing proteins from being made. RNAi therapeutics have the potential to treat disease and help patients in a fundamentally new way.

About Alnylam Pharmaceuticals

Alnylam is a biopharmaceutical company developing novel therapeutics based on RNA interference, or RNAi. The company is leading the translation of RNAi as a new class of innovative medicines with a core focus on RNAi therapeutics for the treatment of genetically defined diseases, including ALN-TTR for the treatment of transthyretin-mediated amyloidosis (ATTR), ALN-PCS for the treatment of severe hypercholesterolemia, ALN-HPN for the treatment of refractory anemia, and ALN-APC for the treatment of hemophilia. As part of its aAlnylam 5x15^TMa strategy, the company expects to have five RNAi therapeutic products for genetically defined diseases in advanced stages of clinical development by the end of 2015. Alnylam has additional partner-based programs in clinical or development stages, including ALN-RSV01 for the treatment of respiratory syncytial virus (RSV) infection, ALN-VSP for the treatment of liver cancers, and ALN-HTT for the treatment of Huntingtonas disease. The companyas leadership position on RNAi therapeutics and intellectual property have enabled it to form major alliances with leading companies including Merck, Medtronic, Novartis, Biogen Idec, Roche, Takeda, Kyowa Hakko Kirin, and Cubist. In addition, Alnylam and Isis co-founded Regulus Therapeutics Inc., a company focused on discovery, development, and commercialization of microRNA therapeutics; Regulus has formed partnerships with GlaxoSmithKline and Sanofi. Alnylam has also formed Alnylam Biotherapeutics, a division of the company focused on the development of RNAi technologies for application in biologics manufacturing, including recombinant proteins and monoclonal antibodies. Alnylamas VaxiRNAa" platform applies RNAi technology to improve the manufacturing processes for vaccines; GlaxoSmithKline is a collaborator in this effort. Alnylam scientists and collaborators have published their research on RNAi therapeutics in over 100 peer-reviewed papers, including many in the worldas top scientific journals such as Nature, Nature Medicine, Nature Biotechnology, and Cell. Founded in 2002, Alnylam maintains headquarters in Cambridge, Massachusetts. For more information, please visit [ www.alnylam.com ].

Alnylam Forward-Looking Statements

Various statements in this release concerning Alnylamas future expectations, plans and prospects, including without limitation, statements regarding Alnylam's views with respect to the potential for RNAi therapeutics, including ALN-TTR01 and ALN-TTR02, its expectations with respect to the timing and success of its clinical and pre-clinical trials, the expected timing of regulatory filings, including its plan to file an IND or IND equivalent application and initiate clinical trials for ALN-TTR02, its expectations regarding the reporting of data from its ALN-TTR01 clinical trial and potentially its ALN-TTR02 clinical trial, and Alnylamas expectations regarding its aAlnylam 5x15a product strategy, 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, without limitation, Alnylamas ability to discover and develop novel drug candidates, successfully demonstrate the efficacy and safety of its drug candidates, including ALN-TTR01 and ALN-TTR02, the pre-clinical and clinical results for its product candidates, which may not support further development of product candidates, actions of regulatory agencies, which may affect the initiation, timing and progress of clinical trials, obtaining, maintaining and protecting intellectual property, obtaining regulatory approval for products, competition from others using technology similar to Alnylamas and others developing products for similar uses, and Alnylamas ability to establish and maintain strategic business alliances and new business initiatives, as well as those risks more fully discussed in the aRisk Factorsa section of its most recent quarterly report on Form 10-Q on file with the Securities and Exchange Commission. In addition, any forward-looking statements represent Alnylamas views only as of today and should not be relied upon as representing its views as of any subsequent date. Alnylam does not assume any obligation to update any forward-looking statements.