Ironwood Pharmaceuticals and Allergan Initiate Patient Dosing in Phase II Clinical Trial of MD-7246 in Patients with Abdominal Pain Associated with IBS-D

June 3, 2019

– Top-line data from Phase II trial expected in second half 2020 –

CAMBRIDGE, Mass.--(BUSINESS WIRE)-- Ironwood Pharmaceuticals, Inc. (NASDAQ:IRWD), a GI-focused healthcare company, today announced the initiation of patient dosing in a Phase II clinical trial evaluating MD-7246 in patients with abdominal pain associated with irritable bowel syndrome with diarrhea (IBS-D). Data from the Phase II trial are expected in the second half of 2020.

Ironwood and Allergan are evaluating MD-7246, an investigational new product, as an oral, intestinal, non-opioid, pain-relieving agent for patients suffering from abdominal pain associated with certain GI diseases. MD-7246 is a delayed-release formulation of linaclotide designed to provide targeted delivery of linaclotide to the colon, where the majority of the abdominal pain associated with IBS-D is believed to originate, and to limit fluid secretion in the small intestine resulting in minimal impact on bowel function.

“Abdominal pain is a dominant symptom experienced by approximately 16 million people in the U.S. living with IBS-D, and there are a limited number of treatment options for patients seeking effective pain relief,” said Michael Shetzline, M.D., Ph.D., chief medical officer, senior vice president and head of drug development at Ironwood. “Through its delayed release and differentiated mechanism of action, we believe that MD-7246 has the potential to target abdominal pain in patients with IBS-D and look forward to advancing it as a potential abdominal pain-relieving agent for this population. If successful, we hope to explore the broader potential of MD-7246 for the more than 50 million patients estimated to suffer from recurring abdominal pain across a broader range of GI disorders.”

The Phase II trial is a randomized, double-blind, placebo-controlled, parallel-group, dose-range-finding, 12-week study. It is designed to evaluate the safety, tolerability, treatment effect on abdominal pain, and dose response of MD-7246 administered orally to patients with abdominal pain associated with IBS-D. The study is expected to enroll approximately 400 IBS-D patients who are randomized equally across three dose levels of MD-7246 (300, 600 or 1,200 mcg), or matching placebo, administered once daily.

Data from an earlier Phase IIb trial in patients with IBS with constipation (IBS-C) showed that MD-7246, as intended, numerically improved abdominal pain relative to placebo, with no apparent effect on bowel movement function.

About IBS-D
Approximately 16 million patients suffer from IBS-D in the United States. 1,2 These patients report frequent abdominal pain (approximately 86 days of the year), discomfort and bloating, along with stools that are more loose or frequent than usual. 3 More than 80% of surveyed patients report IBS-D symptoms as somewhat to extremely severe.4

About MD-7246
MD-7246 is a delayed release formulation of linaclotide being evaluated by Ironwood and its partner Allergan plc as an oral, non-opioid, pain-relieving agent for patients in the U.S. suffering from abdominal pain associated with IBS with diarrhea (IBS-D). Linaclotide is thought to work in two different ways, based on non-clinical studies: by increasing fluid secretion into the intestine and by decreasing the activity of pain-sensing nerves. MD-7246 is designed to provide targeted delivery of linaclotide to the colon, where the majority of the abdominal pain associated with IBS-D is believed to originate, and to limit fluid secretion in the small intestine resulting in minimal impact on bowel function. Ironwood and Allergan have issued patents and pending patent applications covering MD-7246 that are expected to provide patent coverage into the mid-2030s.

About Ironwood Pharmaceuticals
Ironwood Pharmaceuticals (Nasdaq:IRWD) is a GI-focused healthcare company dedicated to creating medicines that make a difference for patients living with GI diseases. We discovered, developed and are commercializing linaclotide, the U.S. branded prescription market leader for adults with irritable bowel syndrome with constipation (IBS-C) or chronic idiopathic constipation (CIC). We are currently advancing a Phase IIIb trial evaluating the efficacy and safety of linaclotide on multiple abdominal symptoms, including bloating, pain, and discomfort, in adult patients with IBS-C.

We are also advancing two late-stage, first-in-category GI product candidates: IW-3718 is a gastric retentive formulation of a bile acid sequestrant being developed for the potential treatment of persistent gastroesophageal reflux disease, and MD-7246 is a delayed-release formulation of linaclotide that is being evaluated as an oral, intestinal, non-opioid, pain-relieving agent for patients suffering from abdominal pain associated with IBS with diarrhea.

Ironwood was founded in 1998 and is headquartered in Cambridge, Mass. For more information, please visit our website at www.ironwoodpharma.com or www.twitter.com/ironwoodpharma; information that may be important to investors will be routinely posted in both these locations.

Forward-Looking Statements
This press release contains forward-looking statements. Investors are cautioned not to place undue reliance on these forward-looking statements, including, but not limited to, the design of the Phase II clinical trial of MD-7246 in patients with abdominal pain associated with IBS-D, including the target indication and expected enrollment and dosing; the anticipated timing of data from the Phase II trial; the mechanism of action of MD-7246 and linaclotide; the prevalence of abdominal pain associated with certain GI diseases and the unmet need for effective treatment; the potential for MD-7246 to offer IBS-D patients and other patients suffering from a broader range of GI disorders relief from abdominal pain; and the development and regulatory plans for MD-7246. 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 preclinical and clinical development, manufacturing and formulation development; the risk that future clinical studies need to be discontinued for any reason, including safety, tolerability, enrollment, manufacturing or economic reasons; the risk that findings from our completed nonclinical and clinical studies may not be replicated in later studies; efficacy, safety and tolerability of our products and product candidates; the risk that the therapeutic opportunities for MD-7246 are not as we expect; decisions by regulatory and judicial authorities; the risk that we are unable to successfully commercialize MD-7246; the risk that we may never get sufficient patent protection for our products and our product candidates or that we are not able to successfully protect such patents; the outcomes in legal proceedings to protect or enforce the patents relating to our products and product candidates, including ANDA litigation; 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, products or product candidates; the risk that we are unable to manage our operating expenses or cash use for operations, or are unable to commercialize our products, within the guided ranges or otherwise as expected; and the risks listed under the heading "Risk Factors" and elsewhere in Ironwood's Quarterly Report on Form 10-Q for the quarter ended March 31, 2019, and in our subsequent SEC filings. These forward-looking statements (except as otherwise noted) speak only as of the date of this press release, and Ironwood undertakes no obligation to update these forward-looking statements.

1 Grundmann O, Yoon SL. Irritable bowel syndrome: Epidemiology, diagnosis and treatment: An update for health-care practitioners. J Gastroenterol Hepatol. 2010;25:691-699.
2 Quick Facts-United States. United States Census Bureau website. https://www.census.gov/quickfacts/table/PST045215/00. Accessed October 28, 2016.
3 American Society for Gastrointestinal Endoscopy. Understanding Irritable Bowel Syndrome with Diarrhea (also known as IBS-D). Available at: https://www.asge.org/home/for-patients/patient-information/understanding-irritable-bowel-syndrome-with-diarrhea-also-known-as-ibs-d. Accessed May 10, 2019
4 Drossman DA, Morris CB, Schneck S, et al. International survey of patients with IBS: symptom features and their severity, health status, treatments, and risk taking to achieve clinical benefit. J Clin Gastroenterol. 2009;43(6):541–550. doi:10.1097/MCG.0b013e318189a7f9

Media and Investors:
Meredith Kaya, 617-374-5082
Vice President, Investor Relations and Corporate Communications
mkaya@ironwoodpharma.com

Source: Ironwood Pharmaceuticals, Inc.