Merrimack Pharmaceuticals, Inc., a biopharmaceutical company discovering, developing and preparing to commercialize innovative medicines paired with companion diagnostics for the treatment of serious diseases, reported that the first patient has been dosed in a phase 1 clinical study combining MM-121, a fully human monoclonal antibody that targets ErbB3, with one of multiple standard treatment regimens for patients with advanced solid tumours.

The phase 1 study evaluates the safety and pharmacokinetics of MM-121 when administered in combination with these separate chemotherapy regimens. Study sites in North America and the European Union are expected to participate in this trial.  The first patient was enrolled at Fox Chase Cancer Center in Philadelphia, PA.

Merrimack entered into an exclusive, global collaboration and licensing agreement with Sanofi for MM-121 in 2009.