Merck decides not to advance IMO-2055 development for squamous cell carcinoma of the head and neck

Idera Pharmaceuticals (NASDAQ: IDRA) today provides an update on the clinical development of IMO-2055 (EMD 1201081), 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 (Erbitux^®) in patients with first-line squamous cell carcinoma of the head and neck (SCCHN) 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.

“Although we are disappointed that Merck has decided not to advance the development of IMO-2055, we are pleased that Merck KGaA plans to complete the ongoing Phase 2 study of IMO-2055 in combination with Erbitux® and to evaluate follow-on TLR9 agonist compounds”

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.

"Although we are disappointed that Merck has decided not to advance the development of IMO-2055, we are pleased that Merck KGaA plans to complete the ongoing Phase 2 study of IMO-2055 in combination with Erbitux^® and to evaluate follow-on TLR9 agonist compounds," commented Sudhir Agrawal, D. Phil., Chairman and Chief Executive Officer of Idera. "It is important to note that IMO-2055 has been well tolerated in multiple trials both as monotherapy and in combination with targeted anti-cancer agents and, based on the intended mechanism of action of TLR9 agonists and the clinical data generated thus far, we believe a potential use of IMO-2055 is in combination with targeted anti-cancer agents."

The IMO-2055 clinical development program in collaboration with Merck KGaA includes the following studies:

• A Phase 1b clinical trial to investigate multiple ascending dosages of IMO-2055 in combination with cisplatin/5-FU and Erbitux^® in patients with first-line SCCHN. In this trial, treatment with IMO-2055 plus cisplatin/5-FU and Erbitux^® was associated with increased neutropenia and electrolyte imbalances as compared to a clinical trial of cisplatin/5-FU and Erbitux^® (Vermorken J, et al. N Engl J Med 2008; 359:1116). This study has been terminated by Merck KGaA.
• A Phase 2 clinical trial of Erbitux^® with or without IMO-2055 as a second-line treatment in patients with recurrent and/or metastatic SCCHN. This study is ongoing and no serious safety concerns have been observed to date.
• A Phase 1b clinical trial of IMO-2055 in combination with Erbitux^® and FOLFIRI (5-FU/leucovorin/irinotecan) in patients with metastatic colorectal cancer. The trial consisted of two steps, a dose escalation component and a dose expansion component. Merck KGaA has decided not to initiate the dose expansion component. Final analysis of data from the dose escalation part of this study is ongoing.
• A Phase 1b clinical trial of IMO-2055 in combination with erlotinib (Tarceva^®) and bevacizumab (Avastin^®) in patients with advanced non-small cell lung cancer. The study has been completed without safety concerns.