Positive interim data from Idera Pharmaceuticals' Phase 1 trial of IMO-2125 TLR9 agonist presented at 45th EASL

Idera Pharmaceuticals, Inc. (Nasdaq: IDRA) announced today that positive interim data from a Phase 1 clinical trial of IMO-2125, a Toll-like Receptor 9 (TLR9) agonist, in null responder patients with chronic hepatitis C virus (HCV) infection were presented at the 45^th Annual Meeting of the European Association for the Study of the Liver (EASL). The oral presentation, entitled "A Phase 1, Multi-Center, Randomized, Placebo-controlled, Dose-escalation Study of IMO-2125, a TLR9 Agonist, in Hepatitis C Non-responders", was made by John McHutchison, M.D., Associate Director, Duke Clinical Research Institute and Director, Gastroenterology and Hepatology Research, Duke University Medical Center, Principal Investigator for the trial. The presentation provided additional detail from the trial regarding the interim data that was announced in December 2009.

“New therapeutic approaches, including novel classes of immune modulators, are needed for the null responder HCV patient population, who show no benefit from standard of care therapy.”

In this trial, null responder HCV patients received IMO-2125 or placebo treatment once per week for four weeks. IMO-2125 was well tolerated by all patients receiving IMO-2125 through the first four dose levels. These patients showed dose-dependent increases in endogenous interferon-alpha and other anti-viral proteins. In addition, serum concentrations of induced interferon-alpha correlated with decreases in HCV viral load, and six of the eight null responder HCV patients who received IMO-2125 at 0.32 mg/kg/week showed maximum viral load reductions ranging from 1.0 to 3.5 logs at least once during the treatment period.

"In this interim report from a Phase 1 study, the results seen in patients receiving IMO-2125 are encouraging and warrant further study," said Dr. McHutchison. "New therapeutic approaches, including novel classes of immune modulators, are needed for the null responder HCV patient population, who show no benefit from standard of care therapy."

"Results from this first-in-man trial confirm the intended mechanism of action of IMO-2125. Based on these data, we have extended the trial to a fifth dose level and are evaluating dosage and treatment schedules in preparation for a planned Phase 2 trial in combination with ribavirin in the null responder HCV patient population," said Robert Arbeit, M.D., Vice President of Clinical Development at Idera. "In parallel we are conducting a Phase 1 clinical trial of IMO-2125 in combination with ribavirin in treatment-naïve HCV patients."

"We are encouraged with the results to date, which show that IMO-2125 induction of endogenous interferon-alpha and other cytokines correlates with anti-viral activity in this difficult-to-treat patient population," said Sudhir Agrawal, D.Phil., Chief Executive Officer and Chief Scientific Officer at Idera. "IMO-2125 was designed based on our expertise in nucleic acid chemistry and our application of structure-activity relationship studies to the creation of TLR-targeted therapeutics."

The presentation includes results at four dose levels of IMO-2125, 0.04, 0.08, 0.16, and 0.32 mg/kg, administered by weekly subcutaneous injection.