Ironwood Pharmaceuticals 3Q 2021 Investor Update Conference Call

Ironwood Q3 2021 Earnings Update

November 4, 2021

Introduction

Matt Roache

Safe Harbor Statement

This presentation contains forward-looking statements. Investors are cautioned not to place undue reliance on these forward-looking statements, including statements about our ability to execute on our vision and

mission; our strategy, business, financial position and operations, including with respect to maximizing LINZESS® (linaclotide), building an innovative GI pipeline and delivering sustained profits and generating cash flow; the demand, development, commercial availability and commercial potential of linaclotide and the drivers, timing, impact and results thereof; the potential indications for, and benefits of, linaclotide and our ability

to drive LINZESS growth; our ability to successfully execute and the value-creation potential of our strategic priorities, including our efforts to drive LINZESS growth in demand and net sales, enhance linaclotide clinical utility through lifecycle management opportunities, and advance treatments for serious, organic GI diseases; our option to acquire an exclusive license to develop and commercialize CNP-104 in the U.S.; the timing of initiating a clinical to evaluate the safety, tolerability, pharmacodynamic effects and efficacy of CNP-104 in PBC patients; the timing, achievement and payment of certain milestones and royalties under our

agreement with COUR; the potential for CNP-104 to transform the treatment of PBC in the U.S.; the potential for CNP-104 to be the first-to-market treatment that offers patients the opportunity to address the underlying pathology in PBC; the opportunity for COUR's nanoparticle platform (CNP) to treat PBC; the strength of the Company's balance sheet and the Company's ability to return cash to shareholders; the

potential of IW-3300 to be an effective treatment of visceral pain conditions and the size of the IC/BPS and endometriosis populations, as well as our plans to submit an IND with the U.S. FDA and, assuming IND approval, to advance IW-3300 into clinical development (including the timing and results thereof); the status of our development program to investigate the safety and efficacy of LINZESS for children; the preservation of the majority of LINZESS patent coverage for the 72 mcg, 145 mcg and 290 mcg dosage forms; and our financial performance and results; expectations regarding our financial performance and

results, and guidance and expectations related thereto, including expectations related to LINZESS net sales growth, total revenue and adjusted EBITDA. These forward-looking statements speak only as of the date of this presentation, 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 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; the risk that we may never get sufficient 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 our planned investments do not have the anticipated effect on our company revenues; 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; 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 CNP-104 is not successful or that CNP-104 is not successfully commercialized; the risk that the clinical trial for CNP-104 is delayed or not initiated by COUR; FDA 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; 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 Ironwood's Quarterly Report on Form 10- Q for the quarter ended June 30, 2021, and in our subsequent SEC filings.

Ironwood uses non-GAAP financial measures in this presentation, which should be considered only a supplement to, and not a substitute for or superior to, GAAP measures. Refer to the Reconciliation of GAAP Results to Non-GAAP Financial Measures table and to the Reconciliation of GAAP Net Income to Adjusted EBITDA table and related footnotes on slides 19 and 20 of this presentation. Further, Ironwood considers the net profit for the U.S. LINZESS brand collaboration with AbbVie in assessing the product's performance and calculates it based on inputs from both Ironwood and AbbVie. This figure should not be considered a substitute for Ironwood's GAAP financial results. An explanation of our calculation of this figure is provided in the U.S. LINZESS Brand Collaboration table and related footnotes on slide 21 of this presentation.

LINZESS® is a registered trademark of Ironwood Pharmaceuticals, Inc. Any other trademarks referred to in this presentation are the property of their respective owners. All rights reserved

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Today's Agenda

• Introduction
  Matt Roache, Director of Investor Relations
• Q3 Overview, Strategic Priorities and Commercial Performance Tom McCourt, Chief Executive Officer
• Pipeline Update
  Mike Shetzline, Chief Medical Officer
• Q3 Financial Highlights & 2021 Guidance Jason Rickard, Chief Operating Officer

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Q3 Overview and Strategic Priorities

Tom McCourt