Merrimack discontinues last clinical candidate

Merrimack discontinued development of MM-310 -- the company's last remaining product in clinical testing -- after a safety update showed that a Phase I trial in solid tumor patients "would not be able to reach an optimal therapeutic index for MM-310" due to continued observation of cumulative peripheral neuropathy.

Last year, Merrimack Pharmaceuticals Inc. (NASDAQ:MACK) discontinued development of Phase II cancer therapies istiratumab (MM-141) and seribantumab (MM-121)...