Merck KGaA nixes development of Idera Pharma cancer drug

Idera Pharmaceuticals' advancement of a Toll-like receptor agonist against cancer has taken a blow. Partner Merck KGaA has informed the developer ($IDRA) that the German pharma is ending development of a drug in certain patients with a type of cancer of the head and neck due to side effects observed in a Phase I study, Idera reports.

Cambridge, MA-based Idera said the side effects its partner cited in its decision to drop development included decreased levels of a type of white blood cells and low electrolyte levels in patients. The side effects were observed in an early-stage study of the drug (dubbed IMO-2055 or EMD 12010991) as part of a combo treatment with a chemotherapy agent and Erbitux in the first-line setting for the head and neck cancers.

Idera's chief executive, Sudhir Agrawal, was quick to note the signs of life in his company's collaboration with Merck, which started back in 2007 and has been a source of funding and validation for advancing Idera's drugs that target Toll-like receptor 9. (The receptors on cells are supposed to recognize pathogens and spur the innate immune system into action against diseases.) For one, the executive noted that Merck plans to continue its Phase II trial of IMO-2055 in combination with Erbitux as a second-line treatment for squamous cell carcinoma of the head and neck. And Merck will continue to evaluate some of Idera's other Toll-like receptor 9 agonists.

"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," Agrawal said.

Still, Idera's stock dropped 6% in afterhours trading on the bad news.

- here's Idera's release
- see what the AP reported