- New Target-Specific License Provides Non-Exclusive Access to Alnylam Intellectual Property for an RNAi Therapeutic Product -

CAMBRIDGE, Mass. & PASADENA, Calif., Jul 21, 2008 (BUSINESS WIRE) -- Alnylam Pharmaceuticals, Inc. (Nasdaq: ALNY), a leading RNAi
therapeutics company, today announced that it has granted Calando
Pharmaceuticals Inc., a majority-owned subsidiary of Arrowhead
Research Corporation (NASDAQ: ARWR), a new target-specific
InterfeRx(TM) license to discover, develop, and commercialize a
synthetic siRNA directed toward an undisclosed cancer gene target. The
new non-exclusive, gene-specific license agreement includes an Alnylam
right of first negotiation to opt-in for co-development and
co-commercialization of the RNAi therapeutic product in the U.S.
market. Detailed financial terms were not disclosed, but include
upfront, and milestone payments, and royalties on sales of any
products covered by the licensing agreement.

"We are pleased to be granting Calando a new InterfeRx license,
providing them access to Alnylam intellectual property, which we
believe is critical for the development and commercialization of all
RNAi therapeutic products," said Jason Rhodes, Vice President,
Business Development of Alnylam Pharmaceuticals. "Calando has
demonstrated exciting progress with the only clinical stage RNAi
therapeutic oncology program, currently in Phase I trials, and we are
encouraged by the potential for similar success with this new target.
Calando exemplifies the progress in our InterfeRx program, an
important part of our overall strategy to create value today by
leveraging our intellectual property portfolio for the development of
RNAi therapeutics."

"This license from Alnylam represents an important step in our
continued efforts to develop and commercialize novel oncology
therapeutics requiring systemic delivery," said James Hamilton, M.D.,
Chief Executive Officer, Calando Pharmaceuticals. "We are excited by
the success we have seen to date with our RNAi therapeutic programs
targeting cancer, and are looking forward to continuing our work with
Alnylam in this area."

Alnylam created the InterfeRx licensing program to grant licenses
under its intellectual property to biotechnology and pharmaceutical
companies wishing to pursue RNAi therapeutics against specific targets
outside Alnylam's core strategic interests. To date, a total of five
companies are InterfeRx licensees; the license grants cover nine
active target programs including three in clinical development. In
2006, Alnylam granted Calando an InterfeRx license to develop and
commercialize an RNAi therapeutic targeting the M2 subunit of
ribonucleotide reductase ("RRM2") formulated with Calando's
proprietary RONDEL(TM) (RNAi/Oligonucleotide Nanoparticle Delivery)
polymer delivery system.

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 "a major scientific
breakthrough that happens once every decade or so," 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. RNAi therapeutics target the cause of
diseases by potently silencing specific messenger RNAs (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
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 leading the translation of RNAi as a new class of
innovative medicines with peer-reviewed research efforts published in
the world's top scientific journals including Nature, Nature Medicine,
and Cell. The company is leveraging these capabilities to build a
broad pipeline of RNAi therapeutics; its most advanced program is in
Phase II human clinical trials for the treatment of respiratory
syncytial virus (RSV) infection. In addition, the company is
developing RNAi therapeutics for the treatment of a wide range of
disease areas, including hypercholesterolemia, liver cancers, and
Huntington's disease. 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 Medtronic,
Novartis, Biogen Idec, Roche, Takeda, and Kyowa Hakko Kogyo. To
reflect its outlook for key scientific, clinical, and business
initiatives, Alnylam has established "RNAi 2010" which includes the
company's plan to significantly expand the scope of delivery solutions
for RNAi therapeutics, have four or more programs in clinical
development, and to form four or more new major business
collaborations, all by the end of 2010. Alnylam is a joint owner of
Regulus Therapeutics LLC, a joint venture focused on the discovery,
development, and commercialization of microRNA therapeutics. Founded
in 2002, Alnylam maintains headquarters in Cambridge, Massachusetts.
For more information, visit www.alnylam.com.

Alnylam Forward-Looking Statements

Various statements in this release concerning Alnylam's future
expectations, plans and prospects, including its views with respect to
the expected importance and scope of its intellectual property rights,
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: Alnylam's approach to discover
and develop novel drugs, which is unproven and may never lead to
marketable products; obtaining, maintaining and protecting
intellectual property; Alnylam's ability to enforce its patents
against infringers and to defend its patent portfolio against
challenges from third parties; Alnylam's ability to obtain additional
funding to support its business activities; Alnylam's ability to
realize future milestones and royalties as well as co-development and
co-commercialization opportunities; Alnylam's dependence on third
parties for development, manufacture, marketing, sales and
distribution of products; obtaining regulatory approval for products;
competition from others using technology similar to Alnylam's and
others developing products for similar uses; Alnylam's dependence on
collaborators; and Alnylam's short operating history; as well as those
risks more fully discussed in the "Risk Factors" 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 Alnylam's 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.

SOURCE: Alnylam Pharmaceuticals, Inc.

Alnylam Pharmaceuticals, Inc.
Investors:
Cynthia Clayton, 617-551-8207
or
Media:
Yates Public Relations
Kathryn Morris, 845-635-9828

Copyright Business Wire 2008