 Merrimack Pharmaceuticals, Inc. MACK today announced that it received a 5 million milestone payment from Ipsen, triggered by Ipsens decision to progress the ongoing multi-part clinical trial evaluating ONIVYDE in patients with small-cell lung cancer into the second randomized portion of the trial focused on efficacy assessment. As a result of this milestone payment, Merrimacks Board of Directors has authorized and declared a special cash dividend of 6.7 million on the Companys common stock the Special Dividend. The Special Dividend is payable on December 23, 2019 to stockholders of record as of the close of business on December 16, 2019. 