Release Details

Idera Pharmaceuticals Announces Presentation of Preclinical Data on IMO-3100, a Lead TLR Antagonist Drug Candidate for Autoimmune Diseases, during American Association of Immunologists Annual Meeting

May 11, 2009

CAMBRIDGE, Mass.--(BUSINESS WIRE)--May. 11, 2009-- Idera Pharmaceuticals, Inc. (Nasdaq: IDRA) today announced the presentation of data from a preclinical study of antagonist effects of IMO-3100 on gene expression profiles induced by ligands of specific Toll-like Receptors (TLRs). The presentation entitled “IMO-3100, an Antagonist of Toll-like Receptors 7 and 9, Modulates Gene Expression and Regulatory Networks Induced by Ligands” was given by Idera scientists during the Autoimmunity session at the 2009 Annual Meeting of The American Association of Immunologists being held in Seattle, WAMay 8-12, 2009. IMO-3100 is the Company’s lead TLR7 and TLR9 antagonist drug candidate for potential application in autoimmune diseases.

The study evaluated expression of over 400 genes in human peripheral blood mononuclear cells in response to a ligand of TLR9, a dual ligand of TLR7/TLR8, and IMO-3100. IMO-3100 alone had minimal modulation of gene expression, whereas the TLR9 and the TLR7/TLR8 ligands each produced unique patterns of gene expression. IMO-3100 inhibited TLR ligand-induced increases in the expression of key immune response genes such as TNF-α, IFN-α, IL-17, and IP-10.

“The gene expression profile data showing antagonist activity of IMO-3100 with ligands of different TLRs help us identify potential markers for use in future clinical studies in autoimmune disease,” said Tim Sullivan, Ph.D., Vice President of Development Programs. “We currently are conducting preclinical development studies to support the filing of an Investigational New Drug application for IMO-3100 by the end of 2009.”

About IMO-3100

IMO-3100 is a Toll-like Receptor 7 (TLR7) and TLR9 antagonist drug candidate currently undergoing preclinical development studies for an intended Investigational New Drug application. Idera’s antagonists of TLRs, such as IMO-3100, are based on synthetic DNA and have been created through extensive structure-activity relationship studies. IMO-3100 has been shown in preclinical assays to suppress immune responses mediated through TLR7 and TLR9. The Company has studied IMO-3100 in preclinical models of lupus, rheumatoid arthritis, multiple sclerosis, psoriasis, and colitis. The Company is also evaluating IMO-3100 and other TLR antagonists in additional preclinical models of autoimmune and inflammatory diseases.

About Idera Pharmaceuticals, Inc.

Idera Pharmaceuticals develops drug candidates to treat infectious diseases, autoimmune and inflammatory 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 such as the studies referred to above 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 Novartis, Merck & Co., and Merck KGaA 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 March 31, 2009, which important factors are incorporated herein by reference. Idera disclaims any intention or obligation to update any forward-looking statements.

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