Ironwood Pharmaceuticals, Inc.

Ironwood Pharmaceuticals, Inc. is a pharmaceutical company whose core business of drug development and regulatory compliance inherently requires animal testing. The company’s primary commercial product, LINZESS (linaclotide), and its pipeline candidates are developed through preclinical research that includes animal studies, a standard practice for FDA approval. The company acknowledges in its public filings that the U.S. FDA routinely inspects facilities responsible for performing this animal testing.

While Ironwood notes in its 2022 ESG Report that animal studies are reviewed by an Institutional Animal Care and Use Committee, and references an FDA roadmap released in April 2025 to replace animal testing with new methodologies, its active drug development pipeline remains reliant on animal data to meet regulatory requirements. There is no public commitment from Ironwood to forgo animal testing where scientifically feasible alternatives exist, nor a timeline for reducing animal use in its research and development processes.