# Merrimack Pharmaceuticals

Source: https://onco.cc/companies/merrimack-pharmaceuticals/  
OnCo record `merrimack-pharmaceuticals` (Company). Data CC BY-NC 4.0, attribute "Data from OnCo (onco.cc)"; commercial use needs a licence.

## TL;DR

Merrimack was the Cambridge biotech behind liposomal irinotecan (Onivyde), approved for pancreatic cancer in 2015 and later sold to Ipsen; its antibody programmes failed and the company wound down.

## Summary

Merrimack Pharmaceuticals, founded in 2000 in Cambridge, Massachusetts, developed MM-398, a liposomal formulation of irinotecan approved in 2015 as Onivyde for metastatic pancreatic cancer after gemcitabine (the NAPOLI-1 trial), which it sold to Ipsen in 2017. Its systems-biology antibody programmes, including the HER3 antibody seribantumab, did not reach approval, and the company later returned remaining assets to shareholders. Its phase 3 trials remain on ClinicalTrials.gov under Merrimack as lead sponsor.

## Fields

- Kind: Company
- Last checked: 2026-09-11
- Also known as: Merrimack Pharmaceuticals, Inc.; Merrimack
- Tags: ctgov-sponsor
- HQ: Cambridge, MA
- Type: biotech
- Website: http://www.merrimackpharma.com

## Sources

- Official website: http://www.merrimackpharma.com
- ClinicalTrials.gov: trials led by Merrimack Pharmaceuticals, Inc.: https://clinicaltrials.gov/search?lead=Merrimack%20Pharmaceuticals%2C%20Inc.
- Wikidata: https://www.wikidata.org/wiki/Q30287940

## Connected records

- cancers: [Pancreatic ductal adenocarcinoma](https://onco.cc/cancers/pancreatic/)
- drugs: [Irinotecan (and liposomal irinotecan)](https://onco.cc/drugs/irinotecan/)
- companies: [Ipsen](https://onco.cc/companies/ipsen/)
- terms: [Clinical trial](https://onco.cc/terms/clinical-trial/), [Pivotal (registrational) trial](https://onco.cc/terms/pivotal-trial/)

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