Senior VicePresident Clinical Research at Alnylam

"ALN-VSP represents Alnylams first IND for a systemically delivered RNAitherapeutic, which is a testament to the very strong progress we have made inachieving delivery of siRNAs," said Akshay Vaishnaw, M.D., Ph.D., Senior VicePresident, Clinical Research at Alnylam. Additional study design details will be provided upon initiation ofthe clinical study. Its discovery has been heralded as"a major scientific breakthrough that happens once every decade or so," andrepresents one of the most promising and rapidly advancing frontiers in biologyand drug discovery today which was awarded the 2006 Nobel Prize for Physiologyor Medicine. RNAi is a natural process of gene silencing that occurs inorganisms ranging from plants to mammals. By harnessing the natural biologicalprocess of RNAi occurring in our cells, the creation of a major new class ofmedicines, known as RNAi therapeutics, is on the horizon.

RNAi therapeuticstarget the cause of diseases by potently silencing specific messenger RNAs(mRNAs), thereby preventing disease-causing proteins from being made. About Alnylam PharmaceuticalsAlnylam is a biopharmaceutical company developing novel therapeutics based onRNA interference, or RNAi. The company is applying its therapeutic expertise inRNAi to address significant medical needs, many of which cannot effectively beaddressed with small molecules or antibodies, the current major classes ofdrugs. Alnylam is leading the translation of RNAi as a new class of innovativemedicines with peer-reviewed research efforts published in the worlds topscientific journals including Nature, Nature Medicine, and Cell.

The company isleveraging these capabilities to build a broad pipeline of RNAi therapeutics;its most advanced program is in Phase II human clinical trials for the treatmentof respiratory syncytial virus (RSV) infection and is partnered with Cubist andKyowa Hakko. The companysleadership position in fundamental patents, technology, and know-how relating toRNAi has enabled it to form major alliances with leading companies includingMedtronic, Novartis, Biogen Idec, Roche, Takeda, Kyowa Hakko, and Cubist. Foundedin 2002, Alnylam maintains headquarters in Cambridge, Massachusetts. For moreinformation, please visit http:// Alnylam Forward-Looking StatementVarious statements in this release concerning Alnylams future expectations,plans and prospects, constitute forward-looking statements for the purposes ofthe safe harbor provisions under The Private Securities Litigation Reform Act of1995. Actual results may differ materially from those indicated by theseforward-looking statements as a result of various important factors, includingthe companys ability to successfully research and develop products, such asALN-VSP for the treatment of liver cancers, including the possibility thatALN-VSP will not be demonstrated to be safe and effective when tested in humans,as well as those risks more fully discussed in the "Risk Factors" section of itsmost recent quarterly report on Form 10-Q on file with the Securities andExchange Commission. In addition, any forward-looking statements representAlnylams views only as of today and should not be relied upon as representingits views as of any subsequent date.