Nature of Business	6 Months Ended
Jun. 30, 2026
Disclosure Text Block
Nature of Business	1. Nature of Business Ironwood Pharmaceuticals, Inc. (“Ironwood” or the “Company”) is a biotechnology company developing and commercializing life-changing therapies for people living with gastrointestinal (“GI”) and rare diseases. The Company is focused on the development and commercialization of innovative product opportunities in areas of significant unmet need, leveraging its demonstrated expertise and capabilities in GI and rare diseases. LINZESS^® (linaclotide), the Company’s commercial product, is the first product approved by the United States Food and Drug Administration (the “U.S. FDA”) in a class of GI medicines called guanylate cyclase type C agonists (“GC-C agonists”) and is indicated, in the U.S., for the treatment of irritable bowel syndrome with constipation (“IBS-C”) in adults and pediatric patients 7 years of age and older, chronic idiopathic constipation (“CIC”) in adults, and functional constipation (“FC”) in pediatric patients ages 2-17 years-old. LINZESS is also available for the treatment of adults with IBS-C or CIC in Mexico and Kingdom of Saudi Arabia, adults with IBS-C or chronic constipation in Japan, and adults with IBS-C in China. Linaclotide is available under the trademarked name CONSTELLA^®for the treatment of adults with IBS-C or CIC and pediatric patients ages 6-17 years old with FC in Canada, and to adults with IBS-C in certain European countries. The Company has strategic partnerships with leading pharmaceutical companies to support the development and commercialization of linaclotide throughout the world. The Company and its partner, AbbVie Inc. (together with its affiliates, “AbbVie”), began commercializing LINZESS in the U.S. in December 2012. Under the Company’s collaboration for North America with AbbVie, total net sales of LINZESS in the U.S., as recorded by AbbVie, are reduced by commercial costs incurred by each party, and the resulting amount is shared equally between the Company and AbbVie. Additionally, development costs are shared equally between the Company and AbbVie. Outside of the U.S., the Company earns royalties as a percentage of net sales of products containing linaclotide as an active ingredient by the Company’s collaboration partners. AbbVie has an exclusive license from the Company to develop and commercialize linaclotide in all countries other than China (including Hong Kong and Macau), Japan and the countries and territories of North America (the “AbbVie License Territory”). In addition, AbbVie has exclusive rights to commercialize linaclotide in Canada as CONSTELLA and in Mexico and Kingdom of Saudi Arabia as LINZESS. Astellas Pharma Inc. (“Astellas”), the Company’s partner in Japan, has an exclusive license to develop, manufacture, and commercialize linaclotide in Japan. Grand Life Sciences (Beijing) Co., Ltd. (together with its affiliates) (“Grand Life Sciences”), the Company’s partner in China since May 2026, has the exclusive right to develop, manufacture, and commercialize products containing linaclotide in China (including Hong Kong and Macau) (the “Grand Life Sciences Territory”). In May 2026, and as further described in Note 4, Collaboration, License and Other Agreements, AstraZeneca AB notified the Company that it has assigned its rights and obligations under the collaboration agreement to Grand Life Sciences. The Company is also advancing apraglutide, a next-generation, synthetic peptide long-acting analog of glucagon-like peptide-2, developed for short bowel syndrome (“SBS”) patients who are dependent on parenteral support (“PS”). The Company was incorporated in Delaware on January 5, 1998 as Microbia, Inc. On April 7, 2008, the Company changed its name to Ironwood Pharmaceuticals, Inc. To date, the Company has dedicated a majority of its activities to the research, development and commercialization of linaclotide, as well as to other research and development programs, including apraglutide.

Nature of Business

6 Months Ended

Jun. 30, 2026

1. Nature of Business

Ironwood Pharmaceuticals, Inc. (“Ironwood” or the “Company”) is a biotechnology company developing and commercializing life-changing therapies for people living with gastrointestinal (“GI”) and rare diseases. The Company is focused on the development and commercialization of innovative product opportunities in areas of significant unmet need, leveraging its demonstrated expertise and capabilities in GI and rare diseases.

LINZESS^® (linaclotide), the Company’s commercial product, is the first product approved by the United States Food and Drug Administration (the “U.S. FDA”) in a class of GI medicines called guanylate cyclase type C agonists (“GC-C agonists”) and is indicated, in the U.S., for the treatment of irritable bowel syndrome with constipation (“IBS-C”) in adults and pediatric patients 7 years of age and older, chronic idiopathic constipation (“CIC”) in adults, and functional constipation (“FC”) in pediatric patients ages 2-17 years-old. LINZESS is also available for the treatment of adults with IBS-C or CIC in Mexico and Kingdom of Saudi Arabia, adults with IBS-C or chronic constipation in Japan, and adults with IBS-C in China. Linaclotide is available under the trademarked name CONSTELLA^®for the treatment of adults with IBS-C or CIC and pediatric patients ages 6-17 years old with FC in Canada, and to adults with IBS-C in certain European countries.

The Company has strategic partnerships with leading pharmaceutical companies to support the development and commercialization of linaclotide throughout the world. The Company and its partner, AbbVie Inc. (together with its affiliates, “AbbVie”), began commercializing LINZESS in the U.S. in December 2012. Under the Company’s collaboration for North America with AbbVie, total net sales of LINZESS in the U.S., as recorded by AbbVie, are reduced by commercial costs incurred by each party, and the resulting amount is shared equally between the Company and AbbVie. Additionally, development costs are shared equally between the Company and AbbVie.

Outside of the U.S., the Company earns royalties as a percentage of net sales of products containing linaclotide as an active ingredient by the Company’s collaboration partners. AbbVie has an exclusive license from the Company to develop and commercialize linaclotide in all countries other than China (including Hong Kong and Macau), Japan and the countries and territories of North America (the “AbbVie License Territory”). In addition, AbbVie has exclusive rights to commercialize linaclotide in Canada as CONSTELLA and in Mexico and Kingdom of Saudi Arabia as LINZESS. Astellas Pharma Inc. (“Astellas”), the Company’s partner in Japan, has an exclusive license to develop, manufacture, and commercialize linaclotide in Japan. Grand Life Sciences (Beijing) Co., Ltd. (together with its affiliates) (“Grand Life Sciences”), the Company’s partner in China since May 2026, has the exclusive right to develop, manufacture, and commercialize products containing linaclotide in China (including Hong Kong and Macau) (the “Grand Life Sciences Territory”). In May 2026, and as further described in Note 4, Collaboration, License and Other Agreements, AstraZeneca AB notified the Company that it has assigned its rights and obligations under the collaboration agreement to Grand Life Sciences.

The Company is also advancing apraglutide, a next-generation, synthetic peptide long-acting analog of glucagon-like peptide-2, developed for short bowel syndrome (“SBS”) patients who are dependent on parenteral support (“PS”).

The Company was incorporated in Delaware on January 5, 1998 as Microbia, Inc. On April 7, 2008, the Company changed its name to Ironwood Pharmaceuticals, Inc. To date, the Company has dedicated a majority of its activities to the research, development and commercialization of linaclotide, as well as to other research and development programs, including apraglutide.