Ironwood Pharmaceuticals : 1Q 2024 Investor Update

Ironwood Pharmaceuticals

Q1 2024 Investor Update

May 9, 2024

Safe Harbor Statement

This presentation contains forward-looking statements within the meaning of the Private Securities Litigation Reform Act of 1995. Investors are cautioned not to place undue reliance on these forward-looking statements, including statements about our ability to execute on our vision; our strategy, business, financial position and operations, including with respect to our strategic priorities; 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; expectations regarding our financial performance and results, and guidance and expectations related thereto, including, without limitation expectations related to LINZESS prescription demand growth, LINZESS U.S. net sales, Ironwood revenue and adjusted EBITDA in 2024; the assessment of the data from the Phase III STARS clinical trial of apraglutide; the efficacy and safety of apraglutide; the potential of CNP-104 to be a disease-modifying therapy for PBC; the progress of ongoing clinical trials and the timing of related data readouts. 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, apraglutide, CNP-104,IW-3300, and other product candidates; the risk that clinical programs and studies, inducing for the linaclotide pediatric program, apraglutide, CNP-104 and IW-3300, 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 studies and clinical trials may not be replicated in later trials and earlier-stage clinical trials may not be predictive of the results we may obtain in later-stage clinical trials or of the likelihood of regulatory approval; the risk of competition or that new products may emerge that provide different or better alternatives for treatment of the conditions that our products are approved to treat; the risk that we are unable to execute on our strategy to in-license externally developed products or product candidates; the risk that we are unable to successfully partner with other companies to develop and commercialize products or product candidates; the risk that healthcare reform and other governmental and private payor initiatives may have an adverse effect upon or prevent our products' or product candidates' commercial success; the efficacy, safety and tolerability of linaclotide and our product candidates; the risk that the commercial and therapeutic opportunities for LINZESS, apraglutide, or our product candidates are not as we expect; decisions by regulatory and judicial authorities; the risk that we may never get additional patent protection for linaclotide, apraglutide, and other product candidates, that patents for linaclotide, apraglutide, 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 the development of the linaclotide pediatric program, apraglutide, CNP-104 and/or IW-3300 are 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; and the risks listed under the heading "Risk Factors" and elsewhere in Ironwood's Annual Report on Form 10-K for the year ended December 31, 2023, 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 Non-GAAP Financial Measures to GAAP Results table and to the Reconciliation of Adjusted EBITDA to GAAP net income table and related footnotes on pages 17 to 19 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 pages 20 and 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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Introduction

Matt Roache

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Today's Agenda

• Introduction
  Matt Roache, Director, Investor Relations
• Overview
  Tom McCourt, Chief Executive Officer
• Pipeline Update
  Mike Shetzline, M.D., Ph.D., Chief Medical Officer
• Commercial Update, Q1 2024 Financial Highlights and FY 2024 Guidance
  Sravan Emany, Chief Financial Officer

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Overview

Tom McCourt

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In Q1 2024, we continued to make significant advancements across our strategic priorities

Maximize

LINZESS

Continue to grow LINZESS demand

and net sales

• +10% Y/Y EUTRx demand growth1
• +18% Y/Y NBRx demand growth2

Q1 Highlights

Advance GI Pipeline

Focus on serious, organic GI diseases

with high unmet patient need

• Reported positive topline results from global Phase III STARS trial of once-weeklyapraglutide in adults with short bowel syndrome with intestinal failure (SBS-IF)
• Reported positive results from Phase II exploratory STARGAZE trial of apraglutide in patients with steroid-refractorygastrointestinal acute Graft-versus-HostDisease (SR GI aGVHD)
• Completed enrollment for CNP-104 Phase II POC study for patients with primary biliary cholangitis (PBC)

Deliver Sustained Profits

and Cash Flow

Apply thoughtful and disciplined capital

allocation decisions

• Generated $45 million in cash from operations
• Repaid $25 million of outstanding principal balance on revolving credit facility in cash
• Ended Q1 2024 with $122 million in cash and cash equivalents

6	1 IQVIA National Prescription Audit. 2 IQVIA Patient Insights.

Pipeline Update

Mike Shetzline

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Primary Endpoint

Apraglutide met its primary endpoint of relative change from baseline in actual weekly parenteral support volume at week 24, a 2x treatment effect relative to placebo, driven by both stoma and colon-in-continuity populations

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Apraglutide's differentiated clinical profile, including its once-weeklyadministration, supports its potential to improve the standard of care for adult patients with SBS who are dependent on PS

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• Demonstrated efficacy across both stoma and colon-in- continuity patients
• Rapid onset of treatment effect observed at week 8 and onward throughout the study
• Enteral autonomy in both stoma and colon-in-continuity patients
• Low prevalence of injection site reactions and abdominal distension, which were in line with placebo
• Ironwood to present additional new data from the STARS Phase 3 study on efficacy, safety, tolerability and compliance at the upcoming Digestive Disease Week® 2024

CNP-104: Phase 2 proof of concept study in Primary Biliary Cholangitis (PBC)

Expect topline data in Q3 2024

CNP-104 has the potential to be a disease-modifying therapy for PBC

42 patients with PBC

Randomized, Double-blinded,placebo-controlled, parallel assignment

Doses:

Placebo, CNP-104 4mg/kg, CNP-104 8mg/kg

IV Infusion on Days 1 and 8

STUDY OBJECTIVES

Safety, tolerability, pharmacodynamics (PD), and efficacy of two doses of CNP-104

KEY OUTCOMES:

• Immunological endpoints (e.g. T-cell response)
• Markers of liver function

		Day 120
CNP-104(4mg/kg)
			20 month Long-Term
CNP-104	(8mg/kg)
	Safety and Durability

Placebo

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