Merrimack's first FDA-approved drug was approved in 2015; Onivyde, a liposome encapsulated version of irinotecan is used for treating pancreatic adenocarcinoma.

[5] In January 2017, French pharmaceutical company Ipsen announced they would be purchasing Onivyde from Merrimack for approximately $1 billion.

[7] On November 13, 2018, the statistical programming director Songjiang Wang, received "six months in prison and one year supervised released" after a guilty verdict was handed down to Wang from a United States District Judge in July 2018 for securities fraud and conspiracy to commit securities fraud.

[8] Also on December 20, 2019, the United States Securities and Exchange Commission charged Wang with Insider trading.

[9] On May 10, 2024, Merrimack announced that the stockholders at a Special Meeting held that day approved the adoption of a Plan of Dissolution.