Ironwood Pharmaceuticals to Present New IW-3300 and Linaclotide Data at Digestive Disease Week® 2022

– Data to be featured in two oral presentations and six posters – – CEO Tom McCourt to receive American Society for Gastrointestinal Endoscopy (ASGE) President’s Award at meeting –

BOSTON--(BUSINESS WIRE)--Ironwood Pharmaceuticals, Inc. (Nasdaq: IRWD), a GI-focused healthcare company, today announced that the company and its collaborators will present eight studies, including two oral presentations, during the Digestive Disease Week^® (DDW) 2022 meeting being held from May 21 through May 24, 2022 in San Diego, CA.

One oral presentation will discuss the impact of novel guanylate cyclase-C agonist IW-3300 on comorbid chronic pelvic and somatic pain in a preclinical model of stress-induced visceral hypersensitivity. Ironwood is focused on advancing the science and understanding of visceral pain and is currently developing IW-3300 for the potential treatment of chronic visceral pain conditions, such as interstitial cystitis/bladder pain syndrome (IC/BPS) and endometriosis. The second oral presentation will summarize results of a post-hoc analysis of linaclotide studies focused on further understanding its treatment effect on abdominal symptoms in patients with Irritable Bowel Syndrome with Constipation (IBS-C). Other studies include preclinical data on the impact of linaclotide on visceral hypersensitivity, data on the impact of linaclotide on pediatric functional constipation (FC) and studies on disease burden of IBS-C and chronic idiopathic constipation (CIC).

At the meeting, Ironwood’s Chief Executive Officer, Tom McCourt will be honored with the American Society for Gastrointestinal Endoscopy (ASGE) President’s Award, which recognizes individuals who have made exceptional contributions to ASGE and its mission over the course of their careers.

“DDW is always an invigorating meeting for scientific minds in the GI community, and we’re thrilled to share findings from eight insightful studies in person this year,” said Mr. McCourt. “We’re particularly excited to showcase new research emphasizing our leadership in the visceral hypersensitivity space, specifically exploring IW-3300’s potential as a treatment option for visceral pain conditions. We are also delighted to share new data that informs our understanding of linaclotide’s treatment effect in patients with IBS-C and from its development program in pediatric patients with functional constipation. In addition, I am honored and humbled to be receiving the ASGE President's Award. I truly believe that when industry and professional organizations work collaboratively, we best position ourselves to advance science and public health.”

In addition to two oral presentations, four additional topics will be presented and two ePosters will be available by Ironwood as well. An overview of all eight presentations is provided below.

IW-3300

• Colon-Targeted Delivery Of Guanylate Cyclase-C Agonist IW-3300 Relieves Comorbid Chronic Pelvic And Somatic Pain In A Rat Model Of Early Life Stress-Induced Colonic Hypersensitivity (oral presentation; presentation number 240), by Casey Ligon, Ph.D., The University of Oklahoma Health Sciences Center, Oklahoma City, OK, will be presented on Saturday, May 21, 4:45 p.m. to 5:00 p.m. PT in room 24

Linaclotide

• Patient-Derived Meaningful Change Thresholds In The Novel Abdominal Score Outcome Measure In Irritable Bowel Syndrome With Constipation (oral presentation; presentation number 179), by Jan Tack, M.D., Ph.D., University of Leuven, Leuven, Belgium, will be presented on Saturday, May 21, 3:00 p.m. to 3:15 p.m. PT in Room 28ABC
• Undiagnosed Irritable Bowel Syndrome with Constipation (IBS-C) and Chronic Idiopathic Constipation (CIC): More Common than we Thought? (presentation number Mo1084), by Brian E. Lacy, M.D., Ph.D., The Mayo Clinic, Jacksonville, FL, will be presented on Monday, May 23, 12:30 p.m. to 1:30 p.m. PT
• Chronic Idiopathic Constipation Sufferers And Treatment Satisfaction: Prescription Vs. Over-The-Counter Medication (presentation number Tu1339), by Brian E. Lacy, M.D., Ph.D., The Mayo Clinic, Jacksonville, FL, on Tuesday, May 24, 12:30 p.m. to 1:30 p.m. PT
• Race-Related Comparisons Of Irritable Bowel Syndrome With Constipation Symptoms, Treatment Response, And Quality Of Life: Results Of A Pooled Analysis Of Linaclotide Clinical Trials (presentation number Tu1364), by Linda Nguyen, M.D., Stanford Health Care, Redwood City, CA, on Tuesday, May 24, 12:30 p.m. to 1:30 p.m. PT
• Safety and Efficacy of Linaclotide in Children Aged 2-5 years With Functional Constipation; Results From a Randomized, Double-blind, Placebo-controlled, Multidose Study (presentation number Tu1390), by Carlo Di Lorenzo, M.D., Nationwide Children’s Hospital, Columbus, OH, on Tuesday, May 24, 12:30 p.m. to 1:30 p.m. PDT
• Colorectal Nociceptive Processing In Ascending Pain Relaying Caudal Ventrolateral Medulla And The Lateral Parabrachial Nuclei Is Increased In A Mouse Model Of Chronic Visceral Hypersensitivity And Is Reversed By Chronic Linaclotide Treatment (ePoster presentation number EP1238), by Andrea Harrington, Ph.D., Flinders University, Adelaide, South Australia
• Descending Pain Modulation Of Colorectal Nociceptive Processing In The Spinal Cord Is Imbalanced In A Mouse Model Of Post-Colitis Chronic Visceral Hypersensitivity And Is Reduced By Chronic Oral Linaclotide Treatment (ePoster presentation number EP1239), by Andrea Harrington, Ph.D., Flinders University, Adelaide, South Australia

About Linaclotide Linaclotide is a guanylate cyclase-C (GC-C) agonist that is thought to work in two ways based on nonclinical studies. Linaclotide binds to the GC-C receptor locally, within the intestinal epithelium. Activation of GC-C results in increased intestinal fluid secretion and accelerated transit and a decrease in the activity of pain-sensing nerves in the intestine. The clinical relevance of the effect on pain fibers, which is based on nonclinical studies, has not been established. In the United States, Ironwood and AbbVie co-develop and co-commercialize LINZESS for the treatment of adults with IBS-C or CIC. In Europe, AbbVie markets linaclotide under the brand name CONSTELLA® for the treatment of adults with moderate to severe IBS-C. In Japan, Ironwood's partner Astellas markets linaclotide under the brand name LINZESS for the treatment of adults with IBS-C or chronic constipation. In China, (including Hong Kong and Macau) Ironwood’s partner Astra Zeneca markets linaclotide under the brand name LINZESS for the treatment of adults with IBS-C. Ironwood is also partnered with AbbVie for development and commercialization of linaclotide in all other territories worldwide. LINZESS® and CONSTELLA® are registered trademarks of Ironwood Pharmaceuticals, Inc. Any other trademarks referred to in this press release are the property of their respective owners. All rights reserved.

LINZESS Important Safety Information INDICATIONS AND USAGE LINZESS (linaclotide) is indicated in adults for the treatment of both irritable bowel syndrome with constipation (IBS-C) and chronic idiopathic constipation (CIC). IMPORTANT SAFETY INFORMATION

Contraindications

• LINZESS is contraindicated in patients less than 2 years of age due to the risk of serious dehydration.
• LINZESS is contraindicated in patients with known or suspected mechanical gastrointestinal obstruction.

Warnings and Precautions Pediatric Risk

• LINZESS is contraindicated in patients less than 2 years of age. In neonatal mice, linaclotide increased fluid secretion as a consequence of age-dependent elevated GC-C agonism resulting in mortality within the first 24 hours due to dehydration. There was no age-dependent trend in GC-C intestinal expression in a clinical study of children 2 to less than 18 years of age; however, there are insufficient data available on GC-C intestinal expression in children less than 2 years of age to assess the risk of developing diarrhea and its potentially serious consequences in these patients. The safety and effectiveness of LINZESS in patients less than 18 years of age have not been established.

Diarrhea

• Diarrhea was the most common adverse reaction in LINZESS-treated patients in the pooled IBS-C and CIC double-blind placebo-controlled trials. The incidence of diarrhea was similar in the IBS-C and CIC populations. Severe diarrhea was reported in 2% of 145 mcg and 290 mcg LINZESS-treated patients, and in &<1% of 72 mcg LINZESS-treated CIC patients. If severe diarrhea occurs, dosing should be suspended, and the patient rehydrated.

Common Adverse Reactions (incidence ≥2% and greater than placebo)

• In IBS-C clinical trials: diarrhea (20% vs 3% placebo), abdominal pain (7% vs 5%), flatulence (4% vs 2%), headache (4% vs 3%), viral gastroenteritis (3% vs 1%) and abdominal distension (2% vs 1%).
• In CIC trials of a 145 mcg dose: diarrhea (16% vs 5% placebo), abdominal pain (7% vs 6%), flatulence (6% vs 5%), upper respiratory tract infection (5% vs 4%), sinusitis (3% vs 2%) and abdominal distension (3% vs 2%). In a CIC trial of a 72 mcg dose: diarrhea (19% vs 7% placebo) and abdominal distension (2% vs &<1%).

Please see full Prescribing Information including Boxed Warning: http://www.allergan.com/assets/pdf/linzess_pi

About IW-3300 Ironwood is currently advancing IW-3300, a guanylate cyclase-C agonist being developed for the potential treatment of visceral pain conditions, such as interstitial cystitis / bladder pain syndrome (IC/BPS) and endometriosis. IC/BPS affects an estimated 4 to 12 million Americans, according to the Interstitial Cystitis Association. An estimated 4 million reproductive-age women in the U.S. have been diagnosed with endometriosis, according to a study published in Gynecologic and Obstetric Investigation. Both diseases have a limited number of treatment options available. Ironwood initiated a clinical study for its IW-3300 program in the first quarter of 2022 to evaluate the safety and tolerability of IW-3300 in healthy volunteers.

About Ironwood Pharmaceuticals Ironwood Pharmaceuticals (Nasdaq: IRWD) is a leading gastrointestinal (GI) healthcare company on a mission to advance the treatment of GI diseases and redefine the standard of care for GI patients. We are pioneers in the development of LINZESS® (linaclotide), the U.S. branded prescription market leader for adults with irritable bowel syndrome with constipation (IBS-C) or chronic idiopathic constipation (CIC). Under the guidance of our seasoned industry leaders, we continue to build upon our history of GI innovation and challenge what has been done before to shape what the future holds. We keep patients at the heart of our R&D and commercialization efforts to reduce the burden of GI diseases and address significant unmet needs.

Founded in 1998, Ironwood Pharmaceuticals is headquartered in Boston, Massachusetts.

We routinely post information that may be important to investors on our website at www.ironwoodpharma.com. In addition, follow us on Twitter and on LinkedIn.

Forward-Looking Statements

This press release contains forward-looking statements. Investors are cautioned not to place undue reliance on these forward-looking statements, including statements about the advancement of our linaclotide pediatrics development program in pediatric patients with functional constipation; the potential impact of linaclotide on pediatric functional constipation and studies on disease burden of IBS-C and CIC; the development of IW-3300 as a potential first in class treatment for visceral pain conditions; and linaclotide’s treatment effect in patients with IBS-C . These forward-looking statements speak only as of the date of this press release, and Ironwood undertakes no obligation to update these forward-looking statements. Each forward-looking statement is subject to risks and uncertainties that could cause actual results to differ materially from those expressed or implied in such statement. Applicable risks and uncertainties include those related to the effectiveness of development and commercialization efforts by us and our partners; preclinical and clinical development, manufacturing and formulation development of linaclotide, CNP-104 and our product candidates; the risk that clinical programs and studies may not progress or develop as anticipated, including that studies are delayed or discontinued for any reason, such as safety, tolerability, enrollment, manufacturing, economic or other reasons; the risk that findings from our completed nonclinical and clinical studies may not be replicated in later studies; the risk that we or our partners are unable to obtain, maintain or manufacture sufficient LINZESS or our product candidates, or otherwise experience difficulties with respect to supply or manufacturing; the efficacy, safety and tolerability of linaclotide and our product candidates; the risk that the therapeutic opportunities for LINZESS or our product candidates are not as we expect; decisions by regulatory and judicial authorities; the risk we may never get additional patent protection for linaclotide and other product candidates, that patents for linaclotide or other products may not provide adequate protection from competition, or that we are not able to successfully protect such patents; the risk that we are unable to manage our expenses or cash use, or are unable to commercialize our products as expected; the risk that we may elect to not exercise our option to acquire the exclusive license for CNP-104; the risk that the development of either CNP-104 and/or IW-3300 is not successful or that any of our product candidates is not successfully commercialized; outcomes in legal proceedings to protect or enforce the patents relating to our products and product candidates, including abbreviated new drug application litigation; the risk that financial and operating results may differ from our projections; developments in the intellectual property landscape; challenges from and rights of competitors or potential competitors; the risk that our planned investments do not have the anticipated effect on our company revenues; developments in accounting guidance or practice; Ironwood’s or AbbVie’s accounting practices, including reporting and settlement practices as between Ironwood and AbbVie; the risk that we are unable to manage our expenses or cash use, or are unable to commercialize our products as expected; the impact of the COVID-19 pandemic; and the risks listed under the heading “Risk Factors” and elsewhere in our Annual Report on Form 10-K for the fiscal year ended December 31, 2021, and in our subsequent SEC filings.

Media: Beth Calitri, 978-417-2031 bcalitri@ironwoodpharma.com

Investors: Greg Martini, 617-374-5230 gmartini@ironwoodpharma.com

Matt Roache, 617-621-8395 mroache@ironwoodpharma.com