MM-141 (istiratumab)

Our research suggests that two pathways — HER3 and IGF-1 — cooperate to drive a master control of cancer cells’ growth.  Merrimack has uniquely discovered that the blockade of these two pathways should be more effective if one drug blocked both receptors rather than two drugs acting separately.

MM-141 is an engineered monoclonal bispecific antibody that blocks both pathways by binding to both the HER3 and IGF-1 receptors.

Merrimack is now prospectively testing the therapeutic effect of MM-141 in pancreatic cancer patients who have high blood levels of IGF-1, the signal for the IGF-1 receptor, which is associated with more aggressive forms of pancreatic cancer, in a randomized, controlled clinical trial.