CAMBRIDGE, Mass.--(BUSINESS WIRE)--Sept. 6, 2007--Idera Pharmaceuticals, Inc. (AMEX: IDP), today announced interim results from a Phase 1 clinical trial being conducted by the Company evaluating IMO-2055, the Company's lead Toll-Like Receptor (TLR) 9 agonist, in combination with gemcitabine and carboplatin in patients with advanced solid tumors. The data were presented in a poster entitled "Initial phase 1 results of gemcitabine, carboplatin and IMO-2055, a toll-like receptor agonist, in patients with advanced solid tumors," by Shakun Malik, M.D., Chief of the Center for Thoracic Medical Oncology at the Lombardi Comprehensive Cancer Center at Georgetown University Medical Center, and principal investigator for the trial, during the 12th World Conference on Lung Cancer taking place in Seoul, Korea, September 2-6, 2007.

The Phase 1 study presented in the poster is the Phase 1 portion of a Phase 1/2 study the Company designed to evaluate the combination. The purpose of the Phase 1 portion was to evaluate the safety of the combination. The Company enrolled 22 patients with advanced, previously treated solid tumors in the study before closing enrollment in July 2007. The data presented in the poster concern 19 patients evaluated for safety and also for efficacy prior to June 2007, including eight patients with non-small cell lung cancer (NSCLC). Patients received three-week cycles of fixed-dose gemcitabine and carboplatin with three escalating doses and three dosage schedules of IMO-2055. Interim data from the 19 patients suggest that it is feasible for the combination to be administered in patients with advanced solid tumors. The only dose-limiting toxicities observed in these patients were neutropenia and thrombocytopenia, which are common side effects observed with gemcitabine and carboplatin. In these 19 patients, the response rate, progression-free survival (PFS) and overall survival are 5%, 4.1 months, and 12.9 months, respectively. In the subset of eight patients with NSCLC, the response rate, PFS and overall survival are 13%, 6.5 months and 12.9 months, respectively. The Company expects to announce final data of this study by the end of 2007.

"Over the course of this trial, we have conducted additional preclinical studies of IMO-2055 in combination with targeted agents, including Tarceva(R), Avastin(R), and Erbitux(R), and have observed encouraging antitumor activity," said Sudhir Agrawal, D. Phil., Chief Executive Officer and Chief Scientific Officer. "As previously announced, we are intending to initiate clinical studies of IMO-2055 in combination with Tarceva and Avastin in NSCLC and in combination with Erbitux in colorectal cancer by the end of the year."

    Idera's Oncology Program

    --  Idera intends to initiate clinical trials to investigate
        IMO-2055 in combination with Tarceva, and in triple
        combination with Tarceva and Avastin, in patients with NSCLC
        as second-line therapy. The Company is preparing to initiate a
        Phase 1b trial in the third quarter of this year to assess the
        safety of the combinations with multiple doses of IMO-2055.
        The Company plans to conduct a four-arm, randomized,
        placebo-controlled Phase 2 trial of the combinations following
        analysis of the results of the Phase 1b trial.

    --  The Company also plans to initiate clinical trials to
        investigate IMO-2055 in combination with Erbitux and Camptosar
        in patients with colorectal cancer as second-line therapy. The
        Company expects to initiate a Phase 1b trial in the fourth
        quarter of this year to assess the safety of this combination
        with multiple doses of IMO-2055. The Company plans to conduct
        a randomized, placebo- controlled Phase 2 trial of the
        combination following analysis of the results of the Phase 1b
        trial.

    --  In Idera's Phase 2, Stage A, clinical evaluation of IMO-2055
        monotherapy in patients with renal cell carcinoma (RCC), the
        Company completed enrollment of the planned 46 treatment-naive
        patients and enrolled 45 of the intended 46 second-line
        patients before closing enrollment of patients on June 29,
        2007. The Company expects that when final data are available,
        it will report the results at an appropriate scientific
        meeting and decide on the next steps for evaluation of
        IMO-2055 in RCC. The Company will not be able to obtain a
        complete set of data from the trial until such time as all
        patients have ceased to receive treatment in the trial. The
        Company expects that initial data from this trial will be
        available in the fourth quarter of 2007 or the first quarter
        of 2008.

    About Idera Pharmaceuticals, Inc.

Idera Pharmaceuticals is a drug discovery and development company that is developing drug candidates to treat cancer and infectious, respiratory, and autoimmune diseases, and for use as vaccine adjuvants. Idera's proprietary drug candidates are designed to modulate specific TLRs, which are a family of immune system receptors. Idera's pioneering DNA chemistry expertise enables it to identify drug candidates for internal development and creates opportunities for multiple collaborative alliances. Idera's most advanced clinical candidate, IMO-2055, is an agonist of TLR9 and is currently in a Phase 2 trial in oncology and in a Phase 1/2 chemotherapy combination trial in oncology. Idera has filed an Investigational New Drug application on a second TLR9 agonist, IMO-2125, for treatment of hepatitis C virus infection. Idera is collaborating with Novartis International Pharmaceutical, Ltd. for the discovery, development, and commercialization of TLR9 agonists for the treatment of asthma and allergy indications. Idera is also collaborating with Merck & Co., Inc. for the use of Idera's TLR7, 8 and 9 agonists in combination with Merck's therapeutic and prophylactic vaccines in the areas of oncology, infectious diseases, and Alzheimer's disease. For more information, visit www.iderapharma.com.

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 early clinical studies or in preclinical studies such as the studies referred to above will be indicative of results obtained in future clinical trials or warrant additional trials; whether interim results of clinical studies, such as the results referred to above, will be reflective of the final results of the studies; 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 and Merck will be successful; whether Idera's cash resources will be sufficient to fund product development and clinical trials; and such other important factors as are set forth under the caption "Risk Factors" in Idera's Quarterly Report on Form 10-Q filed on August 1, 2007, which important factors are incorporated herein by reference. Idera disclaims any intention or obligation to update any forward-looking statements.

Tarceva is a registered trademark of OSI Pharmaceuticals, Inc. Avastin is a registered trademark of Genentech, Inc. Erbitux is a registered trademark of ImClone Systems Incorporated. Camptosar is a registered trademark of Pfizer.

    CONTACT: Idera Pharmaceuticals, Inc.
             Kelly Luethje, 617-679-5519
             kluethje@iderapharma.com
             or
             MacDougall Biomedical Communications
             Chris Erdman, 508-647-0209
             cerdman@macbiocom.com

    SOURCE: Idera Pharmaceuticals, Inc.