Exhibit 99.1

   Alnylam Pharmaceuticals Reports Fourth Quarter and 2006 Financial Results

             - Revenues and Cash Position Significantly Strengthened
                                Year-Over-Year -

    CAMBRIDGE, Mass.--(BUSINESS WIRE)--Feb. 7, 2007--Alnylam
Pharmaceuticals, Inc. (Nasdaq: ALNY), a leading RNAi therapeutics
company, today reported its consolidated financial results for the
quarter and year ended December 31, 2006, company highlights, and
guidance and goals for 2007.

    "The year 2006 was very significant for Alnylam, as we advanced
our mission of building a leading biopharmaceutical company founded on
RNAi. Indeed, we made demonstrable progress with our robust pipeline
of RNAi therapeutics and we exceeded our key business objectives,"
said John Maraganore, Ph.D., President and Chief Executive Officer of
Alnylam Pharmaceuticals. "At a broad strategic level, several 2006
highlights are noteworthy. First, our scientific progress, with major
breakthroughs in delivery, has demonstrated the power of RNAi as a
product platform for innovative medicines. Further, with our clinical
program for the treatment of respiratory syncytial virus infection and
development programs in pandemic flu and hypercholesterolemia, our
pipeline of RNAi therapeutics has advanced toward our goal of
demonstrating human efficacy in the next 12 to 18 months. Finally, our
business was greatly strengthened with continued leadership on
intellectual property, new major alliances with Novartis and Biogen
Idec, significant growth in alliance and federal funding, and a
year-end financial profile with over $215 million in cash. We believe
that 2007 will be an equally important year for Alnylam as we expect
to advance our scientific leadership, pipeline, and business goals as
a leading company in RNAi therapeutics."

    Cash, Cash Equivalents, and Marketable Securities

    At December 31, 2006, Alnylam had cash, cash equivalents, and
marketable securities of $217.3 million, compared to $120.3 million at
September 30, 2006 and $80.0 million at December 31, 2005. The
increase in the company's liquidity from the prior year was primarily
due to combined net proceeds of $163.3 million from public offerings
of common stock in January and December 2006, as well as funding from
collaborators and licensees.

    Revenues

    Revenues in the fourth quarter of 2006 were $7.0 million, as
compared to $1.6 million during the fourth quarter of 2005. Included
in revenues in the fourth quarter of 2006 were $4.6 million of expense
reimbursement, milestone and amortization revenues related to the
company's collaborations with Novartis and $2.4 million of expense
reimbursement and amortization revenues from Biogen Idec, Merck, the
National Institutes of Health (NIH) for Ebola, research reagent and
services licensees, and other sources. Revenues for the year ended
December 31, 2006 were $26.9 million as compared to $5.7 million for
the year ended December 31, 2005. Included in revenues for the year
ended December 31, 2006 were $21.8 million of expense reimbursement,
milestone and amortization revenues related to the company's
collaborations with Novartis, and $5.1 million of expense
reimbursement and amortization revenues from Biogen Idec, Merck, the
NIH for Ebola, InterfeRx(TM) licensees, research reagent and services
licensees, and other sources.

    Net Loss

    The net loss for the quarter ended December 31, 2006 was $8.4
million, or $0.26 per share, as compared to $14.5 million, or $0.56
per share, in the fourth quarter of 2005. The net loss for the fourth
quarter of 2006 included $2.6 million of non-cash stock-based
compensation charges, compared to $1.0 million during the fourth
quarter of 2005. For the year ended December 31, 2006, net loss was
$34.6 million, or $1.09 per share, compared to a net loss of $42.9
million, or $1.96 per share, for the year ended December 31, 2005. The
net loss for the year ended December 31, 2006 included $8.3 million of
non-cash stock-based compensation charges, compared to $4.6 million
during 2005.

    Research and Development Expenses

    Research and development (R&D) expenses were $12.3 million in the
fourth quarter of 2006, including $1.7 million of non-cash stock-based
compensation, as compared to $12.8 million in the fourth quarter of
2005, which included $0.6 million of non-cash stock-based
compensation. The decrease in R&D expenses in the fourth quarter of
2006 was primarily due to payments made in the fourth quarter of 2005,
which did not recur in 2006, totaling $3.7 million to third parties,
primarily to Isis, in accordance with the company's license agreements
with these parties related to the Novartis main alliance. The decrease
was partially offset by increased clinical trial costs related to the
company's clinical program for respiratory syncytial virus (RSV)
infection and higher costs related to an increase in R&D headcount to
support the company's alliances and expanding product pipeline. R&D
expenses were $49.8 million for the year ended December 31, 2006,
including $5.0 million of non-cash stock-based compensation, as
compared to $35.3 million for the year ended December 31, 2005, which
included $2.4 million of non-cash stock-based compensation. R&D
expenses for the year ended December 31, 2006 increased as the company
made progress with its proprietary pipeline, primarily for its PCSK9
program, as well as increased clinical trial costs related to the
company's clinical program for RSV infection, and higher costs related
to an increase in R&D headcount to support the company's alliances and
expanding product pipeline.

    General and Administrative Expenses

    General and administrative (G&A) expenses were $4.6 million in the
fourth quarter of 2006, including $0.9 million of non-cash stock-based
compensation, as compared to $3.7 million in the fourth quarter of
2005, which included $0.4 million of non-cash stock-based
compensation. G&A expenses were $16.6 million for the year ended
December 31, 2006, including $3.3 million of non-cash stock-based
compensation, as compared to $13.9 million for the year ended December
31, 2005, which included $2.2 million of non-cash stock-based
compensation. The increase in G&A expenses for the quarter and year
ended December 31, 2006 was due primarily to increased business
activities, higher facility-related costs and higher non-cash
stock-based compensation expense.

    2007 Financial Guidance

    Alnylam expects that its cash, cash equivalents and marketable
securities balance will be greater than $180.0 million at December 31,
2007.

    "We ended 2006 with a solid financial profile, exceeding our
guidance and completing the year with over $215 million in cash," said
Patricia Allen, Vice President, Finance and Treasurer of Alnylam. "We
believe our current position of financial strength combined with
continued funding from our collaborations will allow us to invest
prudently, yet significantly, in the advancement of RNAi technology
and our pipeline of novel RNAi therapeutics in 2007."

    2006 and Recent Corporate Highlights

    Product Pipeline and Scientific Leadership Highlights

    --  Advanced Development of ALN-RSV01 for RSV Infection. In May
        2006, Alnylam presented results from two Phase I clinical
        studies for ALN-RSV01, its program for the treatment of RSV
        infection, showing ALN-RSV01 to be safe and well tolerated
        when administered in relevant doses intranasally. In October
        2006, Alnylam initiated a Phase I human clinical trial of an
        inhaled formulation of ALN-RSV01 to evaluate safety,
        tolerability, and pharmacokinetics in adult volunteers. In
        November 2006, Alnylam initiated an experimental infection
        study designed to establish a safe and reliable RSV infection
        of the upper respiratory tract in adult volunteers.

    --  Demonstrated Progress with ALN-FLU01 for Pandemic Flu. Alnylam
        has demonstrated activity of ALN-FLU01 toward human clinical
        isolates of the H5N1 virus in pre-clinical studies and has
        advanced this program in development activities with its
        collaborator Novartis.

    --  Announced Development Program with ALN-PCS01 for
        Hypercholesterolemia. Alnylam is advancing a systemically
        delivered RNAi therapeutic targeting the gene PCSK9 for the
        treatment of hypercholesterolemia as its next clinical
        development program. Pre-clinical results for ALN-PCS01 to
        date show in vivo efficacy, potency, and durability for
        silencing of murine and human PCSK9 genes and therapeutic
        efficacy in reducing cholesterol levels.

    --  Advanced Platform for Systemic Delivery of RNAi Therapeutics.
        During the year, Alnylam continued to make progress in
        delivery of RNAi therapeutics, notably with systemic RNAi
        applications. In March 2006, Nature published the work of
        Alnylam scientists demonstrating for the first time in
        non-human primates that a systemically delivered RNAi
        therapeutic can potently silence an endogenous disease-causing
        gene in a clinically relevant manner. Alnylam also made
        progress in its research collaborations with Inex
        Pharmaceuticals Corporation and the Massachusetts Institute of
        Technology on the discovery and development of lipid-based
        nanoparticle formulations for systemic delivery of RNAi
        therapeutics, including those reported recently for its
        hypercholesterolemia program targeting the gene PCSK9.

    --  Advanced Additional Pre-Clinical Programs as Reported at
        Scientific Meetings and in Publications. Throughout 2006,
        Alnylam presented numerous updates on its clinical and
        pre-clinical programs. Since the third quarter, data were
        presented or published in the following venues:

        --  Europaediatrics, October 2006;

        --  Society for Neuroscience, October 2006;

        --  Oligonucleotide Therapeutics Society, October 2006;

        --  Nature Medicine, November 2006; and

        --  Keystone Symposium, January 2007.

    Business Execution Highlights

    --  Signed New Alliance with Novartis for Pandemic Flu. In
        February 2006, Alnylam and Novartis formed a new collaboration
        to develop RNAi therapeutics for pandemic flu. This alliance
        leverages Alnylam's expertise in RNAi and Novartis'
        capabilities and experience in bringing innovative
        therapeutics to patients. In this collaboration, Novartis is
        providing significant funding, and Alnylam and Novartis will
        share in potential profits.

    --  Formed New Alliance with Biogen Idec for PML. In September
        2006, Alnylam formed a collaboration with Biogen Idec to
        develop an RNAi therapeutic for the treatment of progressive
        multifocal leukoencephalopathy (PML). PML is caused by
        infection of the central nervous system with JC virus and can
        occur in certain immune-suppressed patients, including those
        receiving immunomodulatory therapies. Alnylam received an
        upfront payment of $5.0 million and could also receive more
        than $51.0 million in milestone payments and substantial
        undisclosed royalties and utilization fees. Biogen Idec is
        funding all R&D activities under the collaboration.

    --  Awarded Significant Federal Funding and Established Alnylam
        Biodefense(TM). Alnylam significantly expanded its public
        sector-private sector partnership efforts in 2006 by obtaining
        grants and contracts for nearly $25 million in funding.
        Alnylam Biodefense was established to build a robust platform
        for discovering RNAi therapeutics for biopreparedness and
        biodefense applications.

    --  Acquired Key Intellectual Property (IP) and Formed Technology
        Collaboration on Lipid-Based Nanoparticle Delivery of RNAi
        Therapeutics. In January 2007, Alnylam acquired exclusive
        worldwide rights to IP from Inex for discovery, development,
        and commercialization of lipid-based nanoparticle formulations
        for delivery of RNAi therapeutics. Key patents licensed to
        Alnylam include the Wheeler and Semple patent series (U.S.
        Patent Nos. 5,976,567, 6,815,432, and 6,858,225) that broadly
        cover use of so-called "cationic lipids" for delivery of
        oligonucleotides including small interfering RNAs (siRNAs),
        the molecules that mediate RNAi. In addition, the companies
        extended their research collaboration on lipid-based
        formulations.

    --  Continued Leveraging of Intellectual Property. Alnylam granted
        InterfeRx(TM) licenses to its "fundamental" IP to two
        companies, Calando Pharmaceuticals and Quark Biotech, Inc.,
        for development and commercialization of RNAi therapeutics
        toward specific targets that fall outside the core strategic
        areas of Alnylam and its major collaborators. Under these
        agreements, Alnylam received upfront payments and may receive
        annual payments, sublicense income, milestone payments and
        royalties. In addition, the company granted licenses for the
        research reagent and services market under the
        "Kreutzer-Limmer" patent family to Dharmacon, Inc., Integrated
        DNA Technologies, Inc., and Bioneer, Inc.

    --  Completed Successful Follow-On Offerings. In January and
        December 2006, Alnylam significantly strengthened its balance
        sheet by completing common stock offerings resulting in
        approximately $163 million in aggregate net proceeds.

    --  Received Key Industry Recognition. In February 2006, Alnylam
        was honored to receive the James D. Watson Helix Award, the
        biotechnology industry's award for corporate excellence in the
        "emerging/mid-cap" category. The Helix award honors
        biotechnology companies that display leadership in three
        distinct areas: product development, economic growth, and
        corporate citizenship.

    Intellectual Property (IP) Leadership Highlights

    --  United States Patent and Trademark Office (USPTO) Issued Two
        Patents Broadly Covering RNAi Therapeutics. Two key
        fundamental patents from Alnylam's exclusively held "Tuschl
        II" patent series were issued by the USPTO in June and July
        2006. The issued patents (U.S. Patent Nos. 7,056,704 and
        7,078,196) broadly cover methods of making siRNAs with or
        without chemical modifications required to introduce
        "drug-like" properties in RNAi therapeutics for any and all
        disease targets in mammalian cells.

    --  European Patent Office (EPO) Upheld Key Features of Patent.
        Following opposition proceedings in June 2006, the EPO upheld
        amended claims that cover important features, including
        methods, medicaments, and uses of siRNAs, in Alnylam's
        exclusively held "Kreutzer-Limmer I" patent (EP 1144623).

    --  Extended Scope of Chemistry Intellectual Property. The USPTO
        issued a new patent (U.S. Patent No. 7,138,517) that broadly
        covers certain chemical modifications of oligonucleotides used
        to introduce "drug-like" properties in oligonucleotides,
        including siRNAs. This patent is licensed to Alnylam in
        connection with its 2004 alliance with Isis Pharmaceuticals,
        Inc. In 2006, other issued patents from Isis and licensed to
        Alnylam include:

        --  U.S. Patent No. 7,122,649 which broadly covers
            5'-O-conjugated oligonucleotides having a plurality of
            2'-modified nucleosides; and

        --  U.S. Patent No. 7,101,993 which covers compounds including
            2'-O-modified purine nucleosides.

    2007 Goals

    Alnylam announced the following key product and business goals for
2007 in early January.

    Product Goals

    --  Obtain Human Proof-of-Concept Data. Alnylam expects to publish
        or present human proof-of-concept data demonstrating the
        effectiveness of an RNAi therapeutic in human subjects within
        the next 12 to 18 months.

    --  Advance ALN-RSV01 for the Treatment of RSV Infection. Alnylam
        plans to present data from its ongoing Phase I inhalation
        trial in adult volunteers in the first half of 2007. The
        company is also conducting an experimental infection study in
        adult volunteers and expects to begin the treatment protocol
        for this study in the first half of 2007 and present data in
        the second half of 2007. In addition, the company intends to
        initiate a Phase II trial in naturally infected patients in
        the second half of 2007.

    --  Expand Clinical Development Pipeline. Alnylam expects to file
        investigational new drug applications (INDs) for two programs
        in 2007; candidates include ALN-FLU01 for the treatment of
        pandemic influenza and ALN-PCS01 for the treatment of
        hypercholesterolemia. In addition, the company expects to
        announce two new development candidates as it continues to
        expand its pipeline of RNAi therapeutics.

    --  Maintain Leadership Position with Systemic Delivery and
        microRNAs. The company expects to continue its efforts to
        optimize systemic delivery for RNAi therapeutics and plans to
        present or publish new non-human primate data in the first
        half of 2007. Also this year, Alnylam plans to publish two or
        more major papers related to in vivo efficacy for RNAi
        therapeutics delivered systemically and two or more papers
        from its research progress on microRNAs and "antagomirs,"
        chemically synthesized molecules that can work to silence
        disease-causing microRNAs.

    Business Goals

    --  Form Major New Alliance(s). Alnylam intends to form one or
        more new alliance(s) with leading companies to continue to
        develop and fund its growing pipeline of RNAi therapeutics.

    --  Expand Intellectual Property Position. The company expects to
        further augment its fundamental IP position by obtaining
        multiple patent issuances and grants in the U.S. and Europe
        over the course of the year.

    --  Monetize Intellectual Property Position. The company plans to
        realize additional near-term value from its IP estate by
        granting more than five new InterfeRx or research product
        licenses.

    --  Leverage Alliances. Alnylam expects to receive more than $25
        million in alliance-based funding in 2007, which includes
        expected R&D funding and achievement of additional objectives
        under its alliances with collaborators including Merck,
        Medtronic, Novartis, and Biogen Idec.

    --  Maintain Solid Financial Performance. In 2007, Alnylam aims to
        maintain a solid financial position while executing on its
        product and business goals, and expects to end the year with
        greater than $180.0 million in cash.

    Conference Call Information

    Alnylam will host a conference call at 4:30 p.m. ET on February 7,
2007 to discuss 2006 fourth quarter and year-end financial results and
recent corporate developments. The call may be accessed by dialing
800-299-7928 (domestic) or 617-614-3926 (international) five minutes
prior to the start time and provide the passcode 79614148.

    A replay of the call will be available from 6:30 p.m. ET on
February 7, 2007, until February 14, 2007. To access the replay,
please dial 888-286-8010 (domestic) or 617-801-6888 (international),
and provide the passcode 94382017. A live audio webcast of the call
will also be available on the "Investors" section of the company's
website, www.alnylam.com. An archived webcast will be available on the
company's website approximately two hours after the event and will be
archived for 14 days thereafter.

    About RNA Interference (RNAi)

    RNA interference, or RNAi, is a naturally occurring mechanism
within cells for selectively silencing and regulating specific genes.
The discovery of RNAi has been widely acknowledged as a major
breakthrough in biology, and the technology was recognized for its
potential broad impact in medicine with the award of the 2006 Nobel
Prize for Physiology or Medicine. 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
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 I 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, Novartis, and Biogen Idec. The company,
founded in 2002, maintains global headquarters in Cambridge,
Massachusetts, and has an additional operating unit in Kulmbach,
Germany. For more information, visit www.alnylam.com.

    Alnylam Forward-Looking Statements

    Various statements in this release concerning our future
expectations, plans and prospects, including, without limitation,
statements related to future expectations, plans, and prospects, our
clinical development plans for ALN-RSV01, ALN-FLU01, ALN-PCS01 and our
other product candidates, the use of siRNAs to achieve genetic
silencing of disease-causing genes, effective and clinically relevant
delivery of direct and systemic RNAi applications, building a robust
platform for developing RNAi therapeutics to combat biological
threats, our product goals and business goals for 2007, including
without limitation, the filing of an IND for ALN-FLU01 and ALN-PCS01,
forming additional alliances and projections for the amount and
sufficiency of cash, cash equivalents and marketable securities,
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.



                    ALNYLAM PHARMACEUTICALS, INC.
      UNAUDITED CONDENSED CONSOLIDATED STATEMENTS OF OPERATIONS
               (In thousands, except per share amounts)

                                Three Months Ended     Year Ended
                                   December 31,        December 31,
                                ------------------ -------------------
                                 2006      2005      2006      2005
                                -------- --------- --------- ---------

Net revenues                    $ 6,981  $  1,552  $ 26,930  $  5,716
                                -------- --------- --------- ---------

Cost and expenses:
 Research and development (1)    12,343    12,762    49,798    35,319
 General and administrative (1)   4,629     3,707    16,633    13,869
                                -------- --------- --------- ---------
   Total costs and expenses      16,972    16,469    66,431    49,188
                                -------- --------- --------- ---------
   Loss from operations          (9,991)  (14,917)  (39,501)  (43,472)
                                -------- --------- --------- ---------
Other income (expense):
 Interest income                  1,824       790     6,177     1,549
 Interest expense                  (296)     (252)   (1,029)     (969)
 Other income (expense)              25      (112)     (255)      (22)
                                -------- --------- --------- ---------
   Total other income (expense)   1,553       426     4,893       558
                                -------- --------- --------- ---------
Net loss                        $(8,438) $(14,491) $(34,608) $(42,914)
                                ======== ========= ========= =========

Net loss per common share -
 basic and diluted (2)          $ (0.26) $  (0.56) $  (1.09) $  (1.96)
                                ======== ========= ========= =========

Weighted average common shares
 used to compute basic and
 diluted net loss per common
 share                           33,048    25,731    31,890    21,949


(1) Non-cash stock-based
 compensation expense included
 in these amounts are as
 follows:
   Research and development     $ 1,675  $    616  $  5,006  $  2,431
   General and administrative       934       386     3,298     2,166
(2) Non-cash stock-based
 compensation expense per
 common share included in these
 amounts are as follows:        $ (0.08) $  (0.04) $  (0.26) $  (0.21)




                    Alnylam Pharmaceuticals, Inc.
           Unaudited Condensed Consolidated Balance Sheets
                            (In thousands)

- ----------------------------------------------------------------------
                                           December 31,  December 31,
                                               2006         2005
- ----------------------------------------------------------------------
Cash, cash equivalents and marketable
 securities                                    $217,260       $80,002
Collaboration receivables                         3,829           609
Prepaid expenses and other current assets         1,695         1,803
Property and equipment, net                      12,173        10,580
Long-term restricted cash                         2,313         2,313
Intangible and other assets                       2,736         3,041
- ----------------------------------------------------------------------
Total Assets                                   $240,006       $98,348
- ----------------------------------------------------------------------
Other current liabilities                       $11,781        $7,750
Deferred revenue                                 17,930        20,833
Notes payable, net of current portion             5,919         5,519
Deferred rent                                     3,202         2,467
Total stockholders' equity                      201,174        61,779
- ----------------------------------------------------------------------
Total Liabilities and Stockholders' Equity     $240,006       $98,348
- ----------------------------------------------------------------------


    This selected financial information should be read in conjunction
with the consolidated financial statements and notes thereto included
in Alnylam's Annual Report on Form 10-K which includes the audited
financial statements for the year ended December 31, 2005.

    CONTACT: Alnylam Pharmaceuticals, Inc.
             Cynthia Clayton, 617-551-8207
             Director, Investor Relations and Corporate Communications
             or
             Patricia Allen, 617-551-8362
             Vice President, Finance and Treasurer