"Dr. MacCoss' extensive accomplishments include critical contributions to bringing many important drugs to market," said James B. Wyngaarden, M.D., Chairman of Idera. "We welcome Dr. MacCoss to Idera's Board of Directors and look forward to his participation in helping the Company fulfill the potential of its pipeline of drug candidates for diverse indications."

"Idera is a pioneer of nucleic acid-based therapeutic approaches, including antisense and immune modulation through Toll-like Receptors," said Dr. MacCoss. "I am pleased to have the opportunity to work with its industry-leading scientific team as a member of the Board and to help the Company make strategic decisions in advancing its broad pipeline of drug candidates."

Dr. MacCoss was formerly Group Vice President for Chemical Research at the Schering-Plough Research Institute. In this role, he provided strategic leadership to the Chemistry Research group globally and was the Head of Chemistry at the Schering-Plough Kenilworth, N.J. site. In addition, he chaired the Schering-Plough Global Chemistry Council, a forum for formulating global chemistry strategies. Prior to his work with Schering-Plough, from 1982-2008, Dr. MacCoss held positions with increasing levels of responsibility at Merck Research Laboratories in the areas of Exploratory, Medicinal, and Basic Chemistry. In 1999, he became Vice President, Basic Chemistry at the Rahway, N.J. site, and in 2003, he became the Vice President of Basic Chemistry and Drug Discovery Sciences and the Deputy Site-Head of the Rahway Site; he was also Chairman of the Merck World-Wide Chemistry Council. At Merck, Dr. MacCoss led a medicinal chemistry group that synthesized the first approved oral Substance P antagonist, Emend^(R) (aprepitant), and a novel intravenous prodrug of Emend (fosaprepitant dimeglumine) for Injection. In 2004, Dr. MacCoss was awarded a Thomas Edison Award for his contributions to the inventorship of Emend, and in 2007 he received a second Thomas Edison Award for his contributions to Januvia^(R), a marketed DPP-4 inhibitor. In March 2008, Dr. MacCoss was awarded the N.J. American Chemical Society Award for Creativity in Molecular Design and Synthesis; he was admitted as a Fellow of the Royal Society of Chemistry (FRSC) in 2008; and in 2009 was inducted to the American Chemical Society Hall of Fame. He serves on the Advisory Committee of the Executive Dean for the School of Arts and Sciences, Rutgers University and also on the Advisory Board of the Rutgers University Chemistry and Chemical Biology Department. Dr. MacCoss obtained a Ph.D. in organic chemistry from the University of Birmingham in the U.K.

About Idera Pharmaceuticals, Inc.

Idera Pharmaceuticals develops drug candidates to treat infectious diseases, autoimmune diseases, cancer, and respiratory diseases, and for use as vaccine adjuvants. Our proprietary drug candidates are designed to modulate specific Toll-like Receptors, which are a family of immune system receptors that direct immune system responses. Our pioneering DNA and RNA chemistry expertise enables us to create drug candidates for internal development and generates opportunities for multiple collaborative alliances. For more information, visit www.iderapharma.com.

Idera Forward Looking Statements

This press release contains forward-looking statements concerning Idera Pharmaceuticals, Inc. that involve a number of risks and uncertainties. For this purpose, any statements contained herein that are not statements of historical fact may be deemed to be forward-looking statements. Without limiting the foregoing, the words "believes," "anticipates," "plans," "expects," "estimates," "intends," "should," "could," "will," "may," and similar expressions are intended to identify forward-looking statements. There are a number of important factors that could cause Idera's actual results to differ materially from those indicated by such forward-looking statements, including whether results obtained in preclinical studies and early clinical trials will be indicative of results obtained in future clinical trials; whether products based on Idera's technology will advance into or through the clinical trial process on a timely basis or at all and receive approval from the United States Food and Drug Administration or equivalent foreign regulatory agencies; whether, if the Company's products receive approval, they will be successfully distributed and marketed; whether the Company's collaborations with Merck KGaA and an affiliate of Merck & Co., Inc. will be successful; whether the patents and patent applications owned or licensed by the Company will protect the Company's technology and prevent others from infringing it; whether Idera's cash resources will be sufficient to fund the Company's operations; and such other important factors as are set forth under the caption "Risk Factors" in Idera's Quarterly Report on Form 10-Q for the three months ended September 30, 2009, which important factors are incorporated herein by reference. Idera disclaims any intention or obligation to update any forward-looking statements.

Emend and Januvia are registered trademarks of Merck Sharp & Dohme Corp., a subsidiary of Merck & Co., Inc.

SOURCE: Idera Pharmaceuticals, Inc.

Idera Pharmaceuticals, Inc.
Kelly Luethje, 617-679-5519
kluethje@iderapharma.com
or
MacDougall Biomedical Communications
Chris Erdman, 781-235-3060
cerdman@macbiocom.com