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CAMBRIDGE, Mass.--([ BUSINESS WIRE ])--[ Alnylam Pharmaceuticals, Inc. ] (Nasdaq: ALNY), a leading RNAi therapeutics company, announced today that it has completed enrollment in its Phase I trial with ALN-TTR02, an RNAi therapeutic targeting the transthyretin (TTR) gene for the treatment of TTR-mediated amyloidosis (ATTR). Alnylam also announced today that it has initiated a Phase II trial with ALN-TTR02 aimed at evaluating clinical activity, safety, and tolerability of multiple once-monthly doses of ALN-TTR02 in ATTR patients. Specifically, the study will evaluate the clinical activity of ALN-TTR02 based on measurement of serum levels of TTR, the disease-causing protein in patients with ATTR. ALN-TTR02 utilizes the companyas proprietary second-generation lipid nanoparticle (LNP) delivery technology using the aMC3a lipid. The company expects to present data from the Phase I trial early in the third quarter of 2012.

"a major scientific breakthrough that happens once every decade or so"

aWe continue to focus on the clinical advancement of ALN-TTR02, the lead effort in our aAlnylam 5x15a product strategy. With dosing completed in the Phase I study, we are on track to report results early in the third quarter. Our Phase II study is now underway, and will evaluate a once-monthly multi-dose regimen in ATTR patients,a said Akshay K. Vaishnaw, M.D., Ph.D., Senior Vice President and Chief Medical Officer of Alnylam. aALN-TTR02 utilizes our proprietary second-generation LNP delivery technology which has shown significant potency improvements in both pre-clinical and clinical studies, including recently reported results from our ALN-PCS hypercholesterolemia program. We look forward to continuing to share clinical data from our ALN-TTR02 program, and, assuming positive results in the current Phase II study, we plan to advance to a pivotal trial in 2013.a

The Phase II trial is an open-label, multi-center, multi-dose, dose-escalation trial designed to enroll approximately 20 ATTR patients. Subjects will be enrolled into cohorts of increasing doses and will receive drug once every four weeks for two cycles. The primary objectives of the study are to evaluate the safety and tolerability of multiple doses of ALN-TTR02 and to measure clinical activity based on serial measurement of circulating serum TTR levels.

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 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 10,000 people worldwide and FAC (familial amyloidotic cardiomyopathy) affects at least 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 options for early stage disease are liver transplantation and tafamidis; 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-TTR02 is a systemically delivered RNAi therapeutic being developed for the treatment of ATTR, including FAP and FAC. ALN-TTR02 is formulated in a proprietary second-generation lipid nanoparticle technology, using the aMC3a lipid. Assuming positive results from the Phase II study, Alnylam expects to start a pivotal trial for ALN-TTR02 in 2013. Alnylam also plans to advance ALN-TTRsc, which utilizes a GalNAc-conjugate delivery approach and subcutaneous dose administration.

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 aAlnylam 5x15a"a

The aAlnylam 5x15a strategy, launched in January 2011, establishes a path for development and commercialization of novel RNAi therapeutics to address genetically defined diseases with high unmet medical need. Products arising from this initiative share several key characteristics including: a genetically defined target and disease; the potential to have a major impact in a high unmet need population; the ability to leverage the existing Alnylam RNAi delivery platform; the opportunity to monitor an early biomarker in Phase I clinical trials for human proof of concept; and the existence of clinically relevant endpoints for the filing of a new drug application (NDA) with a focused patient database and possible accelerated paths for commercialization. By the end of 2015, the company expects to have five such RNAi therapeutic programs in clinical development, including programs in advanced stages, on its own or with a partner. The aAlnylam 5x15a programs include ALN-TTR for the treatment of transthyretin-mediated amyloidosis (ATTR), ALN-APC for the treatment of hemophilia, ALN-PCS for the treatment of severe hypercholesterolemia, ALN-HPN for the treatment of refractory anemia, and ALN-TMP for the treatment of hemoglobinopathies. Alnylam intends to focus on developing and commercializing certain programs from this product strategy itself in the United States and potentially certain other countries; the company will seek development and commercial alliances for other core programs both in the United States and in other global territories.

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, ALN-APC for the treatment of hemophilia, and ALN-TMP for the treatment of hemoglobinopathies. As part of its aAlnylam 5x15^TMa strategy, the company expects to have five RNAi therapeutic products for genetically defined diseases in clinical development, including programs in advanced stages, on its own or with a partner 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 applications 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 Alnylamas views with respect to the potential for RNAi therapeutics, including ALN-TTR02 and ALN-TTRsc, its expectations with respect to the timing and success of its clinical trials for ALN-TTR02, its expectations regarding the reporting of data from its ALN-TTR02 clinical trials, 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-TTR02 and ALN-TTRsc, the pre-clinical and clinical results for these product candidates, which may not support further development of such product candidates, actions of regulatory agencies, which may affect the initiation, timing and progress of clinical trials for such product candidates, 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.