) today provides an update on the clinical development of IMO-2055, a TLR9 agonist for cancer treatment being developed by Merck KGaA, Darmstadt, Germany, under its collaboration with Idera. Merck KGaA has informed Idera that, based on increased incidence of neutropenia and electrolyte imbalances reported in its Phase 1 trial of IMO-2055 in combination with cisplatin/5-FU and cetuximab in patients with first-line squamous cell carcinoma of the head and neck and subsequent re-evaluation of its clinical development program, Merck KGaA has determined that it will not conduct further clinical development of IMO-2055 at this stage. Merck KGaA also has informed Idera that it plans to complete its ongoing Phase 2 trial of IMO-2055 in combination with Erbitux® in second-line patients with recurrent or metastatic SCCHN and to continue evaluating follow-on TLR9 agonists created by Idera under the collaboration.