Item 7. Management’s Discussion and Analysis of Financial Condition and Results of Operations

Forward-Looking Information

The following discussion of our financial condition and results of operations should be read in conjunction with our consolidated financial statements and the notes to those financial statements appearing elsewhere in this Annual Report on Form 10-K. This discussion contains forward-looking statements that involve significant risks and uncertainties. As a result of many factors, such as those set forth under “Risk Factors” in Item 1A of this Annual Report on Form 10-K, our actual results may differ materially from those anticipated in these forward-looking statements.

Discussion and analysis of our financial condition and results of operations for the fiscal year ended December 31, 2022 compared to the fiscal year ended December 31, 2021 is included in Part II, Item 7 – "Management's Discussion and Analysis of Financial Condition and Results of Operations" in our Annual Report on Form 10-K for the fiscal year ended December 31, 2022 filed with the SEC on February 16, 2023.

Overview

We are a GI healthcare company dedicated to advancing the treatment of GI diseases and redefining the standard of care for GI patients. We are focused on the development and commercialization of innovative GI product opportunities in areas of significant unmet need, leveraging our demonstrated expertise and capabilities in GI diseases.

LINZESS® (linaclotide), our commercial product, is the first product approved by the U.S. FDA, in a class of GI medicines called GC-C agonists, and is indicated for adult men and women suffering from IBS-C, or CIC, and for pediatric patients ages 6-17 years-old suffering from FC. LINZESS is available to adult men and women suffering from IBS-C or CIC in the U.S., Mexico, and Saudi Arabia, to adult men and women suffering from IBS-C or chronic constipation in Japan, IBS-C in China and for pediatric patients ages 6-17 with FC in the U.S. Linaclotide is available under the trademarked name CONSTELLA® to adult men and women suffering from IBS-C or CIC in Canada, and to adult men and women suffering from IBS-C in certain European countries.

We have strategic partnerships with leading pharmaceutical companies to support the development and commercialization of linaclotide throughout the world, including with AbbVie in the U.S. and all countries worldwide other than China (including Hong Kong and Macau) and Japan, AstraZeneca in China (including Hong Kong and Macau) and Astellas in Japan.

We also aim to leverage our leading development and commercialization capabilities in GI to bring additional treatment options to GI patients.

In June 2023, we completed a tender offer to purchase outstanding ordinary shares of VectivBio. In December 2023, we completed a squeeze-out merger to acquire all remaining shares. The VectivBio Acquisition was partially funded with $400.0 million of borrowings under a new revolving credit facility, or the Revolving Credit Facility, as further described in Note 10, Debt, to our consolidated financial statements included elsewhere in this Annual Report on Form 10-K. Through the acquisition, the Company is advancing apraglutide, a next-generation, synthetic peptide analog of GLP-2, for rare gastrointestinal diseases, including SBS-IF, as well as several earlier stage assets.

In November 2021, we entered into the COUR Collaboration Agreement, with COUR, that grants us an option to acquire an exclusive license to research, develop, manufacture and commercialize, in the U.S., products containing CNP-104, a tolerizing immune modifying nanoparticle, for the treatment of PBC.

We are also advancing IW-3300, a GC-C agonist, for the potential treatment of visceral pain conditions, such as IC/BPS, and endometriosis.

To date, we have dedicated a majority of our activities to the research, development and commercialization of linaclotide, as well as to the research and development of our other product candidates. Prior to the year ended December 31, 2019, we incurred net losses in each year since inception. For the year ended December 31, 2023, we recorded net loss of approximately $1.0 billion, which included a charge of approximately $1.1 billion related to acquired in-process research and development, or IPR&D, in connection with the VectivBio Acquisition. For the years ended 2022 and 2021, we recorded net income of $175.1 million and $528.4 million, respectively. As of December 31, 2023, we had an

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accumulated deficit of approximately $1.7 billion. We are unable to predict the extent of any future losses or guarantee that our company will be able to maintain positive cash flows.

We were incorporated in Delaware on January 5, 1998 as Microbia, Inc. On April 7, 2008, we changed our name to Ironwood Pharmaceuticals, Inc. We operate in one reportable business segment – human therapeutics.

Key 2023 Financial Highlights

Financial Operations Overview

Revenues. Our revenues are generated primarily through our collaborative arrangements and license agreements related to research and development and commercialization of linaclotide.

The majority of our revenues are generated from the sales of LINZESS in the U.S. We record our share of the net profits and losses from the sales of LINZESS in the U.S. less commercial expenses on a net basis and present the settlement payments to and from AbbVie as collaboration expense or collaborative arrangements revenue, as applicable. Net profits or losses consist of net sales to third-party customers and sublicense income in the U.S. less the cost of goods sold as well as selling, general and administrative expenses. Although we expect net sales to increase over time, the settlement payments between AbbVie and us, resulting in collaborative arrangements revenue or collaboration expense, are subject to fluctuation based on the ratio of selling, general and administrative expenses incurred by each party. In addition, our collaborative arrangements revenue may fluctuate as a result of the timing and amount of license fees and clinical and commercial milestones received and recognized under our current and future strategic partnerships as well as timing and amount of royalties from the sales of linaclotide in the European, Canadian, Mexican, Japanese, or Chinese markets or any other markets where linaclotide receives approval and is commercialized.

Cost of Revenues. Cost of revenues primarily includes costs related to the sales of linaclotide API, finished drug product, and finished goods to our partners, which generally occurs upon shipment for sales of API, finished drug product and finished goods after the material has passed all quality testing required for acceptance by the partner to certain of our partners outside of the U.S.

Research and Development Expense. The core of our research and development strategy is to leverage our demonstrated expertise and capabilities in GI diseases to bring multiple medicines to patients. Research and development expense consists of expenses incurred in connection with the research into and development of products and product candidates. These expenses consist primarily of compensation, benefits and other employee-related expenses, research and development related facility costs, third-party contract costs relating to nonclinical study and clinical trial activities, development of manufacturing processes, regulatory registration of third-party manufacturing facilities, and licensing fees for our product candidates.

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Research and development expenses include amounts owed to AbbVie on an ongoing basis under cost-sharing provisions in our collaboration agreement for linaclotide. Reimbursements received for research and development activities under this agreement are netted against research and development expenses.

Linaclotide. Our commercial product, LINZESS, is commercially available in the U.S. for the treatment of IBS-C or CIC in adults and for FC in pediatric patients ages 6-17 years-old. Linaclotide is also available to adult men and women suffering from IBS-C or CIC in certain countries of the world, including China, Japan, and in a number of E.U. countries.

We and AbbVie continue to explore ways to enhance the clinical profile of LINZESS by studying linaclotide in additional indications, populations and formulations to assess its potential to treat various conditions. In September 2020, based on the Phase IIIb data of linaclotide 290 mcg on the overall abdominal symptoms of bloating, pain and discomfort in adult patients with IBS-C, the U.S. FDA approved our sNDA to include a more comprehensive description of the effects of LINZESS in its approved label.

In addition, we and AbbVie have established a nonclinical and clinical post-marketing plan with the U.S. FDA to understand the safety and efficacy of LINZESS in pediatric patients. In August 2021, the U.S. FDA approved a revised label for LINZESS based on clinical safety data that had been generated thus far in pediatric studies. The updated label modified the boxed warning for risk of serious dehydration and contraindication against use in children to those less than two years of age. The boxed warning and contraindication previously applied to all children less than 18 years of age and less than 6 years of age, respectively.In June 2023, the U.S. FDA approved LINZESS as a once-daily treatment for pediatric patients ages 6-17 years-old with FC, making LINZESS the first and only FDA-approved prescription therapy for FC in this patient population. The safety and effectiveness of LINZESS in patients with FC less than 6 years of age or in patients with IBS-C less than 18 years of age have not been established. Additional clinical pediatric programs in IBS-C and FC are ongoing.

Apraglutide. Refer to Acquired In-Process Research and Development.

CNP-104. Through the COUR Collaboration Agreement, we and COUR are developing CNP-104 for the treatment of PBC, a rare autoimmune disease targeting the liver. In December 2021, the U.S. FDA granted Fast Track Designation to CNP-104. COUR is currently conducting a clinical study to evaluate the safety, tolerability, pharmacodynamic effects and efficacy of CNP-104 in PBC patients, with topline data expected in the third quarter of 2024.

IW-3300. We are developing IW-3300, a GC-C agonist, for the potential treatment of visceral pain conditions, including IC/BPS and endometriosis. We successfully completed Phase I studies to evaluate the safety and tolerability of IW-3300 in healthy volunteers and are continuing the Phase II proof of concept study in IC/BPS.

IW-3718. We were developing IW-3718, a gastric retentive formulation of a bile acid sequestrant, for the potential treatment of refractory gastroesophageal reflux disease, or refractory GERD. In September 2020, we announced that one of our two identical Phase III trials evaluating IW-3718 in refractory GERD did not meet the pre-specified criteria associated with a planned early efficacy assessment and, based on these findings, we discontinued development of IW-3718.

Early research and development. Our early research and development efforts have been focused on supporting our development stage GI programs, including exploring strategic options for further development of certain of our internal programs, as well as evaluating external development-stage GI programs.

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The following table sets forth our research and development expenses related to our product pipeline for the years ended December 31, 2023, 2022, and 2021, respectively. These expenses relate primarily to compensation, benefits and other employee-related expenses and external costs associated with nonclinical studies and clinical trial costs for our product candidates. We allocate costs related to facilities, depreciation, share-based compensation, research and development support services and certain other costs directly to programs.

Year Ended December 31,

Apraglutide(2) 58,244 — —

(1) Includes linaclotide in all indications, populations and formulations.

The lengthy process of securing regulatory approvals for new drugs requires the expenditure of substantial resources. Any failure by us to obtain, or any delay in obtaining, regulatory approvals would materially adversely affect our product development efforts and our business overall.

We and AbbVie are exploring development opportunities to enhance the clinical profile of LINZESS by studying linaclotide in additional indications, populations and formulations to assess its potential to treat various conditions. We cannot currently estimate with any degree of certainty the amount of time or money that we will be required to expend in the future on linaclotide for additional indications, populations or formulations.

Given the inherent uncertainties that come with the development of pharmaceutical products, we cannot estimate with any degree of certainty how our programs will evolve, and therefore the amount of time or money that would be required to obtain regulatory approval to market them.

As a result of these uncertainties surrounding the timing and outcome of any approvals, we are currently unable to estimate precisely when, if ever, linaclotide’s utility will be expanded within its currently approved indications; if or when linaclotide will be developed outside of its current markets, indications, populations or formulations; or when, if ever, any of our other product candidates will generate revenues and cash flows.

We invest carefully in our pipeline, and the commitment of funding for each subsequent stage of our development programs is dependent upon the receipt of clear, supportive data. In addition, we intend to access externally discovered drug candidates that fit within our core strategy. In evaluating these potential assets, we apply the same investment criteria as those used for investments in internally discovered assets.

The successful development of our product candidates is highly uncertain and subject to a number of risks including, but not limited to:

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As a result of the factors discussed above, including the factors discussed under “Risk Factors” in Item 1A of this Annual Report on Form 10-K, we are unable to determine the duration and costs to complete current or future nonclinical and clinical stages of our product candidates or when, or to what extent, we will generate revenues from the commercialization and sale of our product candidates. Development timelines, probability of success and development costs vary widely. We anticipate that we will make determinations as to which additional programs to pursue and how much funding to direct to each program on an ongoing basis in response to the data of each product candidate, the competitive landscape and ongoing assessments of such product candidate’s commercial potential.

We expect to invest in our development programs for the foreseeable future. We will continue to invest in linaclotide, including the investigation of ways to enhance the clinical profile within its currently approved indications, and the exploration of its potential utility in other indications, populations and formulations. We will continue to invest in our GI-focused product candidates as we advance them through pre-clinical and clinical trials, in addition to funding research and development activities under our external collaboration and license agreements.

Acquired In-Process Research and Development. Asset acquisition costs, license fees and development milestone payments related to acquired and in-licensed products and technology are expensed as acquired in-process research and development at the point that they have no established alternative future use.

Through the VectivBio Acquisition, we are advancing apraglutide, a next-generation, long-acting synthetic peptide analog of GLP-2, as a differentiated therapeutic for a wide range of rare diseases, including SBS-IF and aGvHD.

Apraglutide for SBS-IF. We are conducting a Phase III clinical trial, STARS, to assess the safety and efficacy of apraglutide in adult patients with SBS-IF, and expect to report topline results in March 2024. In October 2023, we presented positive final data from the STARS Nutrition Phase II study of apraglutide in patients with SBS-IF and colon-in-continuity during United European Gastroenterology (UEG) Week. We are also conducting open label extension studies to further evaluate the efficacy, safety and tolerability of apraglutide in SBS-IF and to support potential submissions of marketing applications for apraglutide in the U.S., European Union, or E.U., and Japan. In October 2023, we presented positive final data from the STARS Nutrition Phase II study during United European Gastroenterology (UEG) Week. This multicenter, open-label study of nine patients was designed to evaluate the safety, pharmacokinetics, and efficacy of apraglutide on intestinal absorption in adult patients who have SBS-IF and colon-in-continuity.

Apraglutide for aGvHD: We are conducting a Phase II exploratory study, STARGAZE, to evaluate apraglutide in patients with steroid-refractory gastrointestinal aGvHD and expect data in the first quarter of 2024.

Selling, General and Administrative Expense. Selling, general and administrative expense consists primarily of compensation, benefits and other employee-related expenses for personnel in our administrative, finance, legal, information technology, business development, commercial, sales, marketing, communications and human resource functions. Other costs include legal costs of pursuing patent protection of our intellectual property, general and administrative related facility costs, insurance costs and professional fees for accounting, tax, consulting, legal and other services. As we continue to invest in the commercialization of LINZESS and other product candidates, we expect our selling, general and administrative expenses will be substantial for the foreseeable future.

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We include AbbVie’s selling, general and administrative cost-sharing payments in the calculation of the net profits and net losses from the sale of LINZESS in the U.S. and present the net payment to or from AbbVie as collaboration expense or collaborative arrangements revenue, respectively.

Restructuring Expenses. Restructuring expenses pertain to a workforce reduction in April 2023 and restructuring initiatives, which commenced in June 2023 in connection with the VectivBio Acquisition. The workforce reduction and restructuring initiatives are more fully described in Note 16, Workforce Reductions and Restructuring, to our consolidated financial statements appearing elsewhere in this Annual Report on Form 10-K.

Interest Expense and Other Financing Costs. Interest expense consists primarily of cash and non-cash interest costs related to our convertible senior notes and Revolving Credit Facility. Non-cash interest expense consists of amortization of debt issuance costs.

Interest and Investment Income. Interest and investment income consists of interest earned on our cash and cash equivalents, as well as significant financing components of payments due from collaboration partners.

Gain (Loss) on Derivatives. In June 2015, we issued 2.25% Convertible Senior Notes due June 15, 2022, or the 2022 Convertible Notes, and in August 2019, we issued the Convertible Senior Notes. In connection with the issuance of our 2022 Convertible Notes, we entered into convertible note hedge transactions, or the Convertible Note Hedges, and separate note hedge warrant transactions, or the Note Hedge Warrants, with certain financial institutions. Gain (loss) on derivatives consists of the change in fair value of the Convertible Note Hedges and Note Hedge Warrants, which are recorded at fair value at each reporting date and changes in fair value are recorded in our consolidated statements of income (loss). The Convertible Note Hedges and Note Hedge Warrants terminated unexercised upon expiry in June 2022 and April 2023, respectively. The Convertible Note Hedges and Note Hedge Warrants are more fully described in Note 10, Debt, to our consolidated financial statements appearing elsewhere in this Annual Report on Form 10-K.

Income Taxes. We prepare our income tax provision based on our interpretation of the income tax accounting rules and each jurisdiction’s enacted tax laws and regulations. At interim reporting dates, we record our income tax provision by applying our estimated annual effective tax rate to year-to-date pre-tax income, plus adjustments for significant unusual or infrequently occurring items. For additional information refer to Note 14, Income Taxes, to our consolidated financial statements appearing elsewhere in this Annual Report on Form 10-K.

Critical Accounting Policies and Estimates

Our discussion and analysis of our financial condition and results of operations is based upon our consolidated financial statements prepared in accordance with U.S. generally accepted accounting principles. The preparation of these financial statements requires us to make certain estimates and assumptions that may affect the reported amounts of assets and liabilities, the disclosure of assets and liabilities at the date of the consolidated financial statements, and the amounts of revenues and expenses during the reported periods. We base our estimates on our historical experience and on various other assumptions that are believed to be reasonable, the results of which form the basis for making judgments about the carrying values of assets and liabilities. Actual results may differ materially from our estimates under different assumptions or conditions. Changes in estimates are reflected in reported results in the period in which they become known.

We believe that our application of the following accounting policies, each of which require significant judgments and estimates on the part of management, are the most critical to aid in fully understanding and evaluating our reported financial results. Our significant accounting policies are more fully described in Note 2,Summary of Significant Accounting Policies, to our consolidated financial statements appearing elsewhere in this Annual Report on Form 10-K.

Acquisitions

We evaluate acquisitions of assets and other similar transactions to assess whether the transaction should be accounted for as a business combination or asset acquisition by first applying a screen test to determine whether substantially all of the fair value of the gross assets acquired is concentrated into a single identifiable asset or group of similar identifiable assets. If the screen test is met, a single asset or group of assets is not a business and is accounted for

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as an asset acquisition. If the screen test is not met, further determination is required as to whether we have acquired inputs and processes that have the ability to create outputs that would meet the requirements of a business.

We account for business combinations using the acquisition method of accounting, which requires the acquiring entity to recognize the fair value of assets acquired and liabilities assumed and establishes the acquisition date as the fair value measurement point. We determine the fair value of assets acquired and liabilities assumed based on management’s estimate of the fair value of assets acquired and liabilities assumed in the acquisition. Goodwill represents the excess of the purchase price over the fair value of the net tangible and intangible assets acquired. Transaction costs are expensed as incurred.

We account for asset acquisitions that are not determined to be a business combination by recognizing net assets based on the consideration paid, inclusive of transaction costs, on a relative fair value basis. In an asset acquisition, the cost allocated to acquired IPR&D with no alternative future use is charged to research and development expense at the acquisition date. We classify asset acquisitions of acquired IPR&D as investing activities on its consolidated statements of cash flows.

Revenue Recognition

Upon executing a revenue generating arrangement, we assess whether it is probable we will collect consideration in exchange for the good or service it transfers to the customer and perform the following five steps: (i) identify the contract(s) with a customer; (ii) identify the performance obligations in the contract; (iii) determine the transaction price; (iv) allocate the transaction price to the performance obligations in the contract; and (v) recognize revenue when (or as) we satisfy the performance obligations. We must develop assumptions that require significant judgment to determine the standalone selling price for each performance obligation identified in the contract. The assumptions that are used to determine the standalone selling price may include forecasted revenues, development timelines, reimbursement rates for personnel costs, discount rates and probabilities of technical and regulatory success.

Our revenues are generated primarily through collaborative arrangements and license agreements related to the development and commercialization of linaclotide. The terms of the collaborative arrangements and other agreements contain multiple performance obligations which may include (i) licenses, (ii) research and development activities, including participation on joint steering committees, (iii) the manufacture of finished drug product, API, or development materials for a partner, which are reimbursed at a contractually determined rate, and (iv) education or co-promotion activities by our clinical sales specialists. Non-refundable payments to us under these agreements may include (i) up-front license fees, (ii) payments for research and development activities, (iii) payments for the manufacture of finished drug product, API, or development materials, (iv) payments based upon the achievement of certain milestones, (v) payments for sales detailing, promotional support services and medical education initiatives, and (vi) royalties on product sales. Additionally, we receive our share of the net profits or bear our share of the net losses from the sale of linaclotide in the U.S. We have adopted a policy to recognize revenue net of tax withholdings, as applicable.

Collaboration, License, and Other Agreements

Upon licensing intellectual property, we determine if the license is distinct from the other performance obligations identified in the arrangement. We recognize revenues from the transaction price, including non-refundable, up-front fees allocated to the license when the license is transferred to the customer if the license has distinct benefit to the customer. For licenses that are combined with other promises, we assess the nature of the combined performance obligation to determine whether the combined performance obligation is satisfied over time or at a point in time. For performance obligations that are satisfied over time, we evaluate the measure of progress each reporting period and, if necessary, adjust the measure of performance and related revenue recognition.

Our license and collaboration agreements include milestone payments, such as development and other milestones. We evaluate whether the milestones are considered probable of being reached and estimate the amount to be included in the transaction price using the most likely amount method at the inception of the agreement. If it is probable that a significant revenue reversal would not occur, the associated milestone value is included in the transaction price. Milestone payments that are not within our control, such as regulatory approvals, are not considered probable of being achieved until those approvals are received. The transaction price is then allocated to each performance obligation on a relative standalone selling price basis, for which we recognize revenue as or when the performance obligations under the

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contract are satisfied. We re-evaluate the probability of achievement of such milestones and any related constraint at each reporting period, and any adjustments are recorded on a cumulative catch-up basis.

Agreements that include the supply of API or drug product for either clinical development or commercial supply at the customer’s discretion are generally considered as options. We assess if these options provide a material right to our partner, and if so, they are accounted for as separate performance obligations. If we are entitled to additional payments when the customer exercises these options, any additional payments are recorded as revenue when the customer obtains control of the goods, which is typically upon shipment for sales of API and finished drug product.

For agreements that include sales-based royalties, including milestone payments based on the level of sales, and the license is deemed to be the predominant item to which the royalties relate, we recognize revenue when the related sales occur in accordance with the sales-based royalty exception.

Net Profit or Net Loss Sharing

In accordance with Accounting Standards Codification, or ASC, Topic 808, Collaborative Arrangements, or ASC 808, we considered the nature and contractual terms of the arrangement and the nature of our business operations to determine the classification of payments under our collaboration agreements. While ASC 808 provides guidance on classification, the standard is silent on matters of separation, initial measurement, and recognition. Therefore, we apply the separation, initial measurement, and recognition principles of ASC Topic 606, Revenue from Contracts with Customers, to our collaboration agreements.

Our collaborative arrangements revenue generated from sales of LINZESS in the U.S. are considered akin to sales-based royalties. We recognize our share of the pre-tax commercial net profit or net loss generated from the sales of LINZESS in the U.S. in the period the product sales are earned, as reported by AbbVie, and related cost of goods sold and selling, general and administrative expenses as incurred by us and our collaboration partner. These amounts are partially determined based on amounts provided by AbbVie and involve the use of estimates and judgments, such as product sales allowances and accruals related to prompt payment discounts, chargebacks, governmental and contractual rebates, wholesaler fees, product returns, and co-payment assistance costs, which could be adjusted based on actual results in the future. We are highly dependent on AbbVie for timely and accurate information regarding any net revenues realized from sales of LINZESS in the U.S. in accordance with ASC 808, and the related costs, in order to accurately report its results of operations. If we do not receive timely and accurate information or incorrectly estimate activity levels associated with the collaboration at a given point in time, we could be required to record adjustments in future periods.

We record revenue transactions as net product revenue in our consolidated statements of incomeif we are deemed the principal in the transaction, which includes being the primary obligor, retaining inventory risk, and control over pricing. Given that we are not the primary obligor and do not have the inventory risks in the collaboration agreement with AbbVie for North America, we record our share of the net profits or net losses from the sales of LINZESS in the U.S. on a net basis and present the settlement payments to and from AbbVie as collaboration expense or collaborative arrangements revenue, as applicable. We and AbbVie settle the cost sharing quarterly, such that our consolidated statements of incomereflect 50% of the pre-tax net profit or loss generated from sales of LINZESS in the U.S.

Sale of Active Pharmaceutical Ingredient

The Company is not currently responsible for the supply of linaclotide API, finished drug product, finished goods or development materials to its partners, though the Company may provide development materials to certain of its partners on a periodic basis. Sales of such development materials have been and are expected to continue to be immaterial.

We recognize revenue on linaclotide API, finished drug product, finished goods, and development materials when control has transferred to the partner, which generally occurs upon shipment after the material has passed all quality testing required for acceptance by the partner.

Other

Our deferred revenue balance consists of advance billings and payments received from customers in excess of revenue recognized.

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Research and Development Expense

We have committed significant resources into the research and development of our product candidates and intend to continue to do so for the foreseeable future. Research and development expenses are generally expensed as incurred. We capitalize nonrefundable advance payments we make for research and development activities and defer expense recognition until the related goods are received or the related services are performed.

Research and development expenses are comprised of costs incurred in performing research and development activities, including salary, benefits, share-based compensation, and other employee-related expenses; laboratory supplies and other direct expenses; facilities expenses; overhead expenses; third-party contractual costs relating to nonclinical studies and clinical trial activities and related contract manufacturing expenses, development of manufacturing processes and regulatory registration of third-party manufacturing facilities; licensing fees for our product candidates; and other outside expenses.

Clinical trial expenses include expenses associated with CROs. The invoicing from CROs for services rendered can lag several months. We accrue the cost of services rendered in connection with CRO activities based on our estimate of site management, monitoring costs, project management costs, and investigator fees. We maintain regular communication with our CRO vendors to gauge the reasonableness of our estimates. Differences between actual clinical trial expenses and estimated clinical trial expenses recorded have not been material and are adjusted for in the period in which they become known. However, if we incorrectly estimate activity levels associated with the CRO services at a given point in time, we could be required to record material adjustments in future periods. Under our collaboration agreement with AbbVie for North America, we are reimbursed for certain research and development expenses and we net these reimbursements against our research and development expenses as incurred.

Research and development expenses also include up-front payment, non-contingent payment, and milestone payment obligations under the COUR Collaboration Agreement. Recognition of expense for such payments requires judgment with respect to when the obligation is probable.

Share-Based Compensation Expense

We grant awards under our share-based compensation programs, including stock awards, restricted stock awards, or RSAs, restricted stock units, or RSUs (including performance-based RSUs, or PSUs), stock options, and shares issued under our employee stock purchase plan, or ESPP. Share-based compensation is recognized as expense in the consolidated statements of income based on the grant date fair value over the requisite service period, net of estimated forfeitures. We estimate forfeitures over the requisite service period using historical forfeiture activity and record share-based compensation expense only for those awards that are expected to vest.

We estimate the fair value of stock options on the date of grant using the Black-Scholes option-pricing model, which requires the use of subjective assumptions including volatility and expected term, among others. The fair value of stock awards, RSAs, and RSUs is based on the market value of our Class A Common Stock on the date of grant, with the exception of PSUs with market conditions, which are measured using the Monte Carlo simulation method. Discounted stock purchases under our ESPP are valued on the first date of the offering period using the Black-Scholes option-pricing model to compute the fair value of the lookback provision plus the purchase discount.

For awards that vest based on service conditions and market conditions, we use the straight-line method to recognize compensation expense over the respective service period. For awards that contain performance conditions, we determine the appropriate amount to expense based on the anticipated achievement of performance targets, which requires judgment, including forecasting the achievement of future specified targets. At the date performance conditions are determined to be probable of achievement, we record a cumulative expense catch-up, with remaining expense amortized over the remaining service period. Throughout the performance period, we re-assess the estimated performance and update the number of performance-based awards that we believe will ultimately vest. Discounted stock purchases under our ESPP are recognized over the offering period.

Compensation expense related to modified awards is measured based on the fair value for the awards as of the modification date. Any incremental compensation expense arising from the excess of the fair value of the awards on the modification date compared to the fair value of the awards immediately before the modification date is recognized at the modification date or ratably over the remaining service period, as appropriate.

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While the assumptions used to calculate and account for share-based compensation awards represent management’s best estimates, these estimates involve inherent uncertainties and the application of management’s judgment. As a result, if revisions are made to our underlying assumptions and estimates, our share-based compensation expense could vary significantly from period to period.

Income Taxes

We utilize the asset and liability method of accounting for income taxes. Under this method, deferred tax assets and liabilities are determined based on the difference between the financial statement carrying amounts and tax basis of assets and liabilities using enacted tax rates in effect for years in which the temporary differences are expected to reverse. We provide a valuation allowance when it is more likely than not that deferred tax assets will not be realized.

Prior to 2021, we maintained a valuation allowance on the majority of our net operating losses and other deferred tax assets. On a periodic basis, we reassess the valuation allowance on our deferred tax assets, weighing positive and negative evidence to assess the recoverability of the deferred tax assets. During the year ended December 31, 2021, we reassessed the valuation allowance noting the shift of positive evidence outweighing negative evidence, including: continued strong prescription demand growth of LINZESS, continued profitability of a GI-focused business since completing the tax-free spin-off of Cyclerion, and expectations regarding future profitability. After assessing both the positive evidence and negative evidence, we determined it was more likely than not that we will realize the majority of our deferred tax assets and therefore released the majority of our valuation allowance for the deferred tax assets that are expected to be utilized in future years. We will continue to maintain a valuation allowance for deferred tax assets that are unlikely to be realized, which are primarily certain tax credits that are expected to expire prior to utilization.

Significant judgment is required in making these assessments to maintain or reverse our valuation allowances and, to the extent our future expectations change we would have to assess the recoverability of these deferred tax assets at that time. If we determine that our net deferred tax assets are not realizable in a future period, we would record material changes to income tax expense or benefit in that period.

We record uncertain tax positions on the basis of a two-step process. First, we determine whether it is more likely than not that the tax positions will be sustained based on the technical merits of the position. Second, for those tax positions that meet the more-likely-than-not recognition threshold, we recognize the largest amount of tax benefit that is greater than 50 percent likely to be realized upon ultimate settlement with the relevant tax authority. Significant judgment is required in evaluating whether our tax positions meet this two-step process. The nature of the uncertain tax positions is often complex and subject to change, and the amounts at issue can be substantial. We re-evaluate these uncertain tax positions on a quarterly basis based on a number of factors including, but not limited to, changes in facts or circumstances, changes in tax law, and effectively settled issues under audit and new audit activity. Any change in these factors could result in the recognition of a tax benefit or an additional charge to the tax provision.

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Results of Operations

The following discussion summarizes the key factors our management believes are necessary for an understanding of our consolidated financial statements.

Year Ended December 31,

(in thousands)

Revenues:

Costs and expenses:

Restructuring expenses 18,317 —

Acquired in-process research and development 1,095,449 —

Other income (expense):

Interest expense and other financing costs (21,629) (7,598)

Interest and investment income 18,971 9,501

Gain on derivatives 19 182

Other income (expense), net (2,639) 2,085

Year Ended December 31, 2023 Compared to Year Ended December 31, 2022

Revenues

Year Ended

December 31, Change

(in thousands)

Revenues:

Collaborative arrangements revenue. The increase in collaborative arrangements revenue of $32.1 million for the year ended December 31, 2023 compared to the year ended December 31, 2022 was primarily related to a $31.7 million increase in our share of net profits from the sale of LINZESS in the U.S., which was primarily driven by increased prescription demand, partially offset by inventory channel fluctuations.

Cost and Expenses

Year Ended

December 31, Change

(in thousands)

Operating expenses:

Acquired in-process research and development 1,095,449 — 1,095,449

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Research and development. The increase in research and development expenses of $71.8 million for the year ended December 31, 2023 compared to the year ended December 31, 2022 was primarily related to $43.3 million of apraglutide program costs, $11.3 million of share-based compensation and $3.5 million in related payroll taxes recognized immediately after the closing of the VectivBio Acquisition in connection with the vesting acceleration of outstanding stock options and RSUs under VectivBio’s 2021 Equity Incentive Plan, a $6.0 million payment to COUR related to CNP-104 in connection with the amendment of the COUR Collaboration Agreement, a $3.3 million increase in linaclotide program costs, and a $3.2 million increase in external costs associated with other pipeline programs. Research and development expenses for the year ended December 31, 2023 included $15.1 million of acquisition-related costs.

Selling, general and administrative. Selling, general and administrative expenses increased $42.3 million for the year ended December 31, 2023 compared to the year ended December 31, 2022, primarily due to $16.2 million of share-based compensation and $3.0 million in related payroll taxes recognized immediately after the closing of the VectivBio Acquisition in connection with the vesting acceleration of outstanding stock options and RSUs under VectivBio’s 2021 Equity Incentive Plan, $12.9 million of general and administrative costs incurred for operating activities of the acquired VectivBio entities, a $5.8 million increase in compensation, benefits, and other employee-related expenses, a $3.7 million increase of professional services costs, and a $1.6 million increase in sales and marketing activities. Selling, general and administrative expenses for the year ended December 31, 2023 included $25.6 million of acquisition-related costs.

Restructuring expenses. Restructuring expenses were $18.3 million for the year ended December 31, 2023 related to employee severance, benefits and related costs for the headquarters-based workforce reduction and VectivBio Acquisition-related workforce reduction.

Acquired In-Process Research & Development. We incurred approximately $1.1 billion of expense during the year ended December 31, 2023 in connection with the VectivBio Acquisition to acquire apraglutide.

Other Income (Expense), Net

Year Ended

December 31, Change

(in thousands)

Other income (expense):

Interest expense and other financing costs $ (21,629) $ (7,598) $ (14,031)

Total other income (expense), net $ (2,639) $ 2,085 $ (4,724)

Interest expense and other financing costs. Interest expense increased by $14.0 million during the year ended December 31, 2023 compared to the year ended December 31, 2022 primarily due to $15.3 million of interest expense incurred under the revolving credit facility used to partially finance the VectivBio Acquisition in June 2023.

Interest and investment income. Interest and investment income increased by $9.5 million in the year ended December 31, 2023 compared to the year ended December 31, 2022, resulting primarily from an increase in investment interest rates, as well as an increase in investment balances prior to the VectivBio Acquisition.

Gain on derivatives.During the year ended December 31, 2023, we recorded an insignificant gain on derivatives resulting from a decrease in the fair value of the Note Hedge Warrants, which terminated unexercised upon expiry in April 2023.

Income taxes. During the year ended December 31, 2023, we recorded income tax expense of $83.5 million, comprised of non-cash tax expense of $74.1 million and cash tax expense of $9.4 million for state income taxes in certain states in which state taxable income exceeded available net operating losses. During the year ended December 31, 2022, we recorded income tax expense of $77.4 million, comprised of non-cash tax expense of $73.4 million and cash tax expense of $4.0 million for state income taxes in certain states in which state taxable income exceeded available net operating losses.

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Liquidity and Capital Resources

As of December 31, 2023, we had $92.2 million of cash and cash equivalents. Our cash equivalents include amounts held in money market funds, U.S. Treasury securities and commercial paper. We invest cash in excess of immediate requirements in accordance with our investment policy, which limits the amounts we may invest in certain types of investments and requires all investments held by us to be at least A- rated, with a remaining final maturity when purchased of less than twenty-four months, so as to primarily achieve liquidity and capital preservation objectives.

We anticipate our cash balance and our expected net cash inflows from operations to allow us to meet our near-term and long-term cash obligations, which are reflected in our consolidated balance sheets. Our most significant fixed obligations are debt obligations and lease commitments, for which annual payments are disclosed in Note 10, Debt, and Note 7, Leases, respectively, to our financial statements included elsewhere in this Annual Report on Form 10-K.

We may from time to time seek to retire, redeem or repurchase all or part of our outstanding debt through cash purchases and/or exchanges, in open market purchases, privately negotiated transactions, by tender offer or otherwise. Such repurchases, redemptions or exchanges, if any, of our debt will depend on prevailing market conditions, liquidity requirements, contractual restrictions and other factors, and the amounts involved may be material.

In May 2021, our board of directors authorized a program to repurchase up to $150.0 million of our Class A Common Stock. The program was completed in May 2022 and the repurchased shares were retired. Additional information regarding the repurchase program is disclosed in Note 12, Stockholders’ Equity, to our financial statements included elsewhere in this Annual Report on Form 10-K.

Sources of Liquidity

We had incurred losses since our inception in 1998 and until the year ended December 31, 2019. However, after achieving profitability for the years ended December 31, 2020, 2021 and 2022, we incurred a loss of approximately $1.0 billion for year ended December 31, 2023 due to the approximately $1.1 billion IPR&D charge recognized in connection with the VectivBio Acquisition, and had an accumulated deficit of approximately $1.7 billion as of December 31, 2023. We have financed our operations to date primarily through both the private sale of our preferred stock and the public sale of our common stock, debt financings, and cash generated from our operations. As of December 31, 2023, our debt is comprised of $400.0 million aggregate principal amount of convertible notes, due at various dates between 2024 and 2026, and $300.0 million aggregate principal amount outstanding under our Revolving Credit Facility, which we entered into in May 2023 to partially finance the VectivBio Acquisition. The Revolving Credit Facility provides for $500.0 million of borrowing capacity and includes a $10.0 million letter of credit subfacility. Refer to Note 10, Debt, to our condensed consolidated financial statements included elsewhere in this Annual Report on Form 10-K, for information related to our debt obligations, including the Revolving Credit Facility.

Summary of Cash Flows

The following table summarizes cash flows from operating, investing, and financing activities for the years ended December 31, 2023, 2022, and 2021:

Year Ended December 31,

(in thousands)

Net cash provided by (used in):

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Cash Flows from Operating Activities

Net cash provided by operating activities is derived by adjusting net income for non-cash items and changes in operating assets and liabilities, which reflect timing differences between the receipt and payment of cash associated with transactions and when they are recognized in the results of operations.

Net cash inflows during the year ended December 31, 2023 totaled $183.4 million and were derived primarily from collaboration arrangements revenue related to sales of LINZESS in the U.S., partially offset by research and development expenditures for apraglutide and acquisition-related costs in connection with the VectivBio Acquisition.

Net cash inflows during the year ended December 31, 2022 totaled $273.8 million and were derived primarily from collaboration arrangements revenue related to sales of LINZESS in the U.S.

Cash Flows from Investing Activities

Cash used in investing activities for the year ended December 31, 2023 totaled approximately $1.0 billion and pertained primarily to the VectivBio Acquisition.

Cash used in investing activities for the year ended December 31, 2022 totaled $0.1 million and pertained to the purchase of property and equipment.

Cash Flows from Financing Activities

Cash provided by financing activities for the year ended December 31, 2023 totaled $277.2 million and was generated primarily from the incurrence of $400.0 million of borrowings under the Revolving Credit Facility, net of $100.0 million of principal repayments. Additionally, we paid $26.3 million to acquire subsidiary shares from noncontrolling interests to complete the squeeze-out merger in connection with the VectivBio Acquisition.

Cash used in financing activities for the year ended December 31, 2022 totaled $237.6 million and resulted from $126.4 million of share repurchases and repayment of the $120.7 million remaining aggregate principal on the 2022 Convertible Notes upon maturity in June 2022, partially offset by $9.5 million of proceeds from the exercise of stock options and the issuance of shares under our ESPP.

Funding Requirements

We began commercializing LINZESS in the U.S. with our collaboration partner, AbbVie, in the fourth quarter of 2012, and we currently derive a significant portion of our revenue from this collaboration. Our goal is to generate and maintain positive cash flows, driven by increased revenue generated through sales of LINZESS and other commercial activities and financial discipline, while continuing to invest in the development and commercialization of linaclotide, apraglutide, and other product candidates.

Under our collaboration with AbbVie for North America, 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 us and AbbVie. Additionally, we receive royalties from AbbVie based on sales of linaclotide in its licensed territories outside of the U.S. We believe revenues from our LINZESS partnership for the U.S. with AbbVie will continue to constitute a significant portion of our total revenue for the foreseeable future and we cannot be certain that such revenues, as well as the revenues from our other commercial activities, will continue to enable us to generate positive cash flows, or to do so in the timeframes we expect. We also anticipate that we will continue to incur substantial expenses for the next several years as we further develop and commercialize linaclotide in the U.S., developand commercialize other products, including apraglutide, and invest in building our pipeline through internal or external opportunities, including potential payments associated with exercising the Option under the COUR Collaboration Agreement. We believe that our cash on hand as of December 31, 2023 will be sufficient to meet our projected operating needs at least through the next twelve months from the issuance of these financial statements.

Our forecast of the period of time through which our financial resources will be adequate to support our operations, including the underlying revenue expectations and estimates regarding the costs to continue to develop, obtain regulatory approval for, and commercialize linaclotide in the U.S., as well as our expectations regarding revenue

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from Astellas for Japan and AstraZeneca for China (including Hong Kong and Macau), and our goal to generate and maintain positive cash flows, are forward-looking statements that involve risks and uncertainties. Our actual results could vary materially and negatively from these and other forward-looking statements as a result of a number of factors, including the factors discussed in the “Risk Factors” section of this Annual Report on Form 10-K. We have based our estimates on assumptions that may prove to be wrong, and we could utilize our available capital resources sooner than we currently expect.

Due to the numerous risks and uncertainties associated with the development and commercialization of our product candidates, we are unable to estimate precisely the amounts of capital outlays and operating expenditures necessary to develop, obtain regulatory approval for, and commercialize linaclotide, apraglutide and our other product candidates, in each case, for all of the markets, indications, populations and formulations for which we believe each is suited. Our funding requirements will depend on many factors, including, but not limited to, the following:

● the success of our third-party manufacturing activities;

● the success of our research and development efforts;

● the emergence of competing or complementary products;

● the settlement method used for our outstanding convertible notes; and

Financing Strategy

We may, from time to time, consider additional funding through a combination of new collaborative arrangements, strategic alliances, and additional equity and debt financings or from other sources. We will continue to manage our capital structure and to consider all financing opportunities, whenever they may occur, that could strengthen our long-term liquidity profile. Any such capital transactions may or may not be similar to transactions in which we have engaged in the past. There can be no assurance that any such financing opportunities will also be available on acceptable terms, if at all.

Off-Balance Sheet Arrangements

We do not have any relationships with unconsolidated entities or financial partnerships, such as entities often referred to as structured finance or special purpose entities, that would have been established for the purpose of

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facilitating off-balance sheet arrangements or other contractually narrow or limited purposes. As such, we are not exposed to any financing, liquidity, market or credit risk that could arise if we had engaged in those types of relationships. We enter into guarantees in the ordinary course of business related to the guarantee of our own performance and the performance of our subsidiaries.

New Accounting Pronouncements

For a discussion of recent accounting pronouncements, refer to Note 2, Summary of Significant Accounting Policies, to our consolidated financial statements appearing elsewhere in this Annual Report on Form 10-K. We did not otherwise adopt any new accounting pronouncements during the fiscal year ended December 31, 2023 that had a material effect on our consolidated financial statements included in this report.

Item 7A. Quantitative and Qualitative Disclosures about Market Risk

Interest Rate Risk

We are exposed to market risk related to changes in interest rates. We invest our cash in a variety of financial instruments, principally securities issued by the U.S. government and its agencies, including collateralized reverse repurchase agreements, and money market instruments, as well as commercial paper. The goals of our investment policy are preservation of capital, fulfillment of liquidity needs and fiduciary control of cash and investments. We also seek to maximize income from our investments without assuming significant risk.

Our primary exposure to market risk is interest income sensitivity, which is affected by changes in the general level of interest rates, particularly because our investments are in short-term marketable securities. Due to the primarily short-term duration of our investment portfolio and the low risk profile of our investments, an immediate 1% change in interest rates would not have a material effect on the fair market value of our portfolio. Accordingly, we would not expect our operating results or cash flows to be affected to any significant degree by the effect of a sudden change in market interest rates on our investment portfolio.

We do not believe our cash and cash equivalents have significant risk of default or illiquidity. While we believe our cash and cash equivalents do not contain excessive risk, we cannot provide absolute assurance that in the future our investments will not be subject to adverse changes in market value. In addition, we maintain significant amounts of cash and cash equivalents at one or more financial institutions that are in excess of federally insured limits. Given the potential instability of financial institutions, we cannot provide assurance that we will not experience losses on these deposits.

Our Convertible Senior Notes bear interest at a fixed rate and therefore have minimal exposure to changes in interest rates; however, because these interest rates are fixed, we may be paying a higher interest rate, relative to market, in the future if our credit rating improves or other circumstances change.

We are exposed to market risks related to fluctuations in interest rates relating to our four-year secured $500.0 million Revolving Credit Facility. The increase or decrease in annual interest expense resulting from a 10% increase or decrease in the applicable interest rate is $2.2 million.

Equity Price Risk

Our convertible notes include conversion and settlement provisions that are based on the price of our Class A Common Stock at conversion or maturity of the notes. The amount of cash we may be required to pay is determined by the price of our Class A Common Stock. The fair values of our convertible notes are dependent on the price and volatility of our Class A Common Stock and will generally increase or decrease as the market price of our common stock changes.

To minimize the impact of potential dilution to our common stock upon conversion of the notes, we entered into the Convertible Note Hedges and Note Hedge Warrants, with respect to the 2022 Convertible Notes, and the Capped Calls, with respect to the 2024 Convertible Notes and 2026 Convertible Notes. The Convertible Note Hedges and Note Hedge Warrants terminated unexercised upon expiry in June 2022 and April 2023, respectively.

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The convertible notes and derivatives are more fully described in Note 10, Debt, in the accompanying notes to our consolidated financial statements appearing elsewhere in this Annual Report on Form 10-K.

Foreign Currency Risk

We are also exposed to risks related to changes in foreign currency exchange rates relating to our foreign operations. The functional currency of our international subsidiaries is the local currency. We are exposed to foreign currency risk to the extent that we enter into transactions denominated in currencies other than our subsidiaries’ respective functional currencies. We are also exposed to unfavorable fluctuations of the U.S. dollar, which is our reporting currency, against the currencies of our operating subsidiaries when their respective financial statements are translated into U.S. dollars for inclusion in our consolidated financial statements. We do not currently hedge our foreign currency exchange rate risk. Foreign currency has not had, nor do we believe that a decrease or increase in any foreign currency exchange rates would have, a material impact on our results of operations.

Item 8. Financial Statements and Supplementary Data

Our consolidated financial statements, together with the independent registered public accounting firm, Ernst & Young LLP (PCAOB ID: 42), report thereon, appear at pages F-1 through F-47, of this Annual Report on Form 10-K.

Item 9. Changes in and Disagreements with Accountants on Accounting and Financial Disclosure

None.

Item 9A. Controls and Procedures

Limitations on Effectiveness of Controls and Procedures

In designing and evaluating our disclosure controls and procedures, management recognizes that any controls and procedures, no matter how well designed and operated, can provide only reasonable assurance of achieving the desired control objectives. In addition, the design of disclosure controls and procedures must reflect the fact that there are resource constraints and that management is required to apply judgment in evaluating the benefits of possible controls and procedures relative to their costs.

Evaluation of Disclosure Controls and Procedures

As required by Rule 13a-15(b) of the Securities Exchange Act of 1934, or Exchange Act, our management, including our principal executive officer and our principal financial officer, conducted an evaluation as of the end of the period covered by this Annual Report on Form 10-K of the effectiveness of the design and operation of our disclosure controls and procedures. Based on that evaluation, our principal executive officer and principal financial officer concluded that our disclosure controls and procedures are effective at the reasonable assurance level in ensuring that information required to be disclosed by us in the reports that we file or submit under the Exchange Act is recorded, processed, summarized and reported within the time periods specified in the SEC’s rules and forms. Disclosure controls and procedures include, without limitation, controls and procedures designed to ensure that information required to be disclosed by us in the reports we file under the Exchange Act is accumulated and communicated to our management, including our principal executive officer and principal financial officer, as appropriate to allow timely decisions regarding required disclosure.

Management’s Report on Internal Control Over Financial Reporting

Our management is responsible for establishing and maintaining adequate internal control over our financial reporting. Internal control over financial reporting is defined in Rules 13a-15(f) and 15d-15(f) under the Exchange Act as the process designed by, or under the supervision of, our Chief Executive Officer and Chief Financial Officer, and effected by our board of directors, management and other personnel, to provide reasonable assurance regarding the reliability of our financial reporting and the preparation of our financial statements for external purposes in accordance with generally accepted accounting principles, and includes those policies and procedures that:

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As permitted by guidance issued by the SEC that an assessment of internal control over financial reporting of a recently acquired business may be omitted from management's evaluation of disclosure controls and procedures, management excluded an assessment of the internal controls of VectivBio, which we acquired on June 29, 2023, from its evaluation of the effectiveness of our disclosure controls and procedures. VectivBio represented approximately 5% of total assets and 6% of total liabilities as of December 31, 2023, and less than 1% and 2% of revenues and net loss, respectively, for the year ended December 31, 2023.

Under the supervision and with the participation of our management, including our Chief Executive Officer and Chief Financial Officer, we conducted an evaluation of the effectiveness of our internal control over financial reporting based on the framework provided in Internal Control—Integrated Framework issued by the Committee of Sponsoring Organizations of the Treadway Commission (2013 framework). Based on this evaluation, our management concluded that our internal control over financial reporting was effective as of December 31, 2023.

The effectiveness of our internal control over financial reporting as of December 31, 2023 has been audited by Ernst and Young LLP, an independent registered public accounting firm, as stated in their report, which is included herein.

Changes in Internal Control Over Financial Reporting

As required by Rule 13a-15(d) of the Exchange Act, our management, including our principal executive officer and our principal financial officer, conducted an evaluation of the internal control over financial reporting to determine whether any changes occurred during the quarter ended December 31, 2023 that have materially affected, or are reasonably likely to materially affect, our internal controls over financial reporting.

Based on management’s evaluation, our principal executive officer and principal financial officer concluded no changes during the quarter ended December 31, 2023 materially affected, or were reasonably likely to materially affect, our internal controls over financial reporting.

Report of Independent Registered Public Accounting Firm

To the Stockholders and the Board of Directors of Ironwood Pharmaceuticals, Inc.

Opinion on Internal Control Over Financial Reporting

We have audited Ironwood Pharmaceuticals, Inc.’s internal control over financial reporting as of December 31, 2023, based on criteria established in Internal Control—Integrated Framework issued by the Committee of Sponsoring Organizations of the Treadway Commission (2013 framework) (the COSO criteria). In our opinion, Ironwood Pharmaceuticals, Inc. (the Company) maintained, in all material respects, effective internal control over financial reporting as of December 31, 2023, based on the COSO criteria.

As indicated in the accompanying Management’s Report on Internal Control Over Financial Reporting, management’s assessment of and conclusion on the effectiveness of internal control over financial reporting did not include the internal controls of VectivBio Holding AG, which is included in the 2023 consolidated financial statements of the Company and constituted approximately 5% and 6% of total assets and total liabilities, respectively, as of December 31, 2023 and less than 1% and 2% of revenues and net loss, respectively, for the year then ended. Our audit of internal control over financial reporting of the Company also did not include an evaluation of the internal control over financial reporting of VectivBio Holding AG.

We also have audited, in accordance with the standards of the Public Company Accounting Oversight Board (United States) (PCAOB), the consolidated balance sheets of the Company as of December 31, 2023 and 2022, the related

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consolidated statements of income (loss), comprehensive income (loss), stockholders’ equity (deficit) and cash flows for each of the three years in the period ended December 31, 2023, and the related notes and our report dated February 16, 2024 expressed an unqualified opinion thereon.

Basis for Opinion

The Company’s management is responsible for maintaining effective internal control over financial reporting and for its assessment of the effectiveness of internal control over financial reporting included in the accompanying Management’s Report on Internal Control Over Financial Reporting. Our responsibility is to express an opinion on the Company’s internal control over financial reporting based on our audit. We are a public accounting firm registered with the PCAOB and are required to be independent with respect to the Company in accordance with the U.S. federal securities laws and the applicable rules and regulations of the Securities and Exchange Commission and the PCAOB.

We conducted our audit in accordance with the standards of the PCAOB. Those standards require that we plan and perform the audit to obtain reasonable assurance about whether effective internal control over financial reporting was maintained in all material respects.

Our audit included obtaining an understanding of internal control over financial reporting, assessing the risk that a material weakness exists, testing and evaluating the design and operating effectiveness of internal control based on the assessed risk, and performing such other procedures as we considered necessary in the circumstances. We believe that our audit provides a reasonable basis for our opinion.

Definition and Limitations of Internal Control Over Financial Reporting

A company’s internal control over financial reporting is a process designed to provide reasonable assurance regarding the reliability of financial reporting and the preparation of financial statements for external purposes in accordance with generally accepted accounting principles. A company’s internal control over financial reporting includes those policies and procedures that (1) pertain to the maintenance of records that, in reasonable detail, accurately and fairly reflect the transactions and dispositions of the assets of the company; (2) provide reasonable assurance that transactions are recorded as necessary to permit preparation of financial statements in accordance with generally accepted accounting principles, and that receipts and expenditures of the company are being made only in accordance with authorizations of management and directors of the company; and (3) provide reasonable assurance regarding prevention or timely detection of unauthorized acquisition, use, or disposition of the company’s assets that could have a material effect on the financial statements.

Because of its inherent limitations, internal control over financial reporting may not prevent or detect misstatements. Also, projections of any evaluation of effectiveness to future periods are subject to the risk that controls may become inadequate because of changes in conditions, or that the degree of compliance with the policies or procedures may deteriorate.

/s/ Ernst & Young LLP

Boston, Massachusetts

February 16, 2024

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Item 9B. Other Information

During the quarter ended December 31, 2023, the following directors and officers (as defined in Rule 16a-1(f) under the Exchange Act) of the Company adopted or terminated a “Rule 10b5-1 trading arrangement” or “non-Rule 10b5-1 trading arrangement,” as each term is defined in Item 408(a) of Regulation S-K, for the purchase or sale of our securities, the material terms of which are set forth in the table below.

PART III

Item 10. Directors, Executive Officers and Corporate Governance

We have adopted a code of business conduct and ethics applicable to our directors, officers, employees, consultants and all their immediate family or other household members. A copy of that code is available on our corporate website at http://www.ironwoodpharma.com. Any amendments to the code of business conduct and ethics, and any waivers thereto involving any of our directors or executive officers, will be also available on our corporate website. A printed copy of these documents will be made available upon request. The content on our website is not incorporated by reference into this Annual Report on Form 10-K.

The other information required by this item is incorporated by reference from our proxy statement for our 2024 Annual Meeting of Stockholders.

Item 11. Executive Compensation

The information required by this item is incorporated by reference from our proxy statement for our 2024 Annual Meeting of Stockholders.

Item 12. Security Ownership of Certain Beneficial Owners and Management and Related Stockholder Matters

The information relating to security ownership of certain beneficial owners of our common stock and information relating to the security ownership of our management required by this item is incorporated by reference from our proxy statement for our 2024 Annual Meeting of Stockholders.

The table below sets forth information with regard to securities authorized for issuance under our equity compensation plans as of December 31, 2023. As of December 31, 2023, we had four active equity compensation plans, each of which was approved by our stockholders:

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● 2019 Equity Incentive Plan;

● Amended and Restated 2019 Equity Incentive Plan; and

● Amended and Restated 2010 Employee Stock Purchase Plan.

(a) (b) (c)

Equity compensation plans not approved by security holders — — —

Item 13. Certain Relationships and Related Transactions, and Director Independence

The information required by this item is incorporated by reference from our proxy statement for our 2024 Annual Meeting of Stockholders.

Item 14. Principal Accountant Fees and Services

The information required by this item is incorporated by reference from our proxy statement for our 2024 Annual Meeting of Stockholders.

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PART IV

Item 15. Exhibits and Financial Statement Schedules

1. List of documents filed as part of this report

2. Consolidated Financial Statement Schedules

No schedules are submitted because they are not applicable, not required or because the information is included in the Consolidated Financial Statements or Notes to Consolidated Financial Statements.

3. Exhibits

Incorporated by reference herein

Number Description Form Date

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21.1* Subsidiaries of Ironwood Pharmaceuticals, Inc.

23.1* Consent of Independent Registered Public Accounting Firm

97* Policy for Recoupment of Incentive Compensation

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101.SCH* XBRL Taxonomy Extension Schema Document

101.CAL* XBRL Taxonomy Extension Calculation Linkbase Document

101.LAB* XBRL Taxonomy Extension Label Linkbase Database

101.PRE* XBRL Taxonomy Extension Presentation Linkbase Document

101.DEF* XBRL Taxonomy Extension Definition Linkbase Document

* Filed herewith.

‡ Furnished herewith.

# Management contract or compensatory plan, contract, or arrangement.

Item 16. Form10-K Summary

None.

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SIGNATURES

Pursuant to the requirements of Section 13 or 15(d) of the Securities Exchange Act of 1934, the registrant has duly caused this report to be signed on its behalf by the undersigned, thereunto duly authorized, in the City of Boston, Commonwealth of Massachusetts, on the 16th day of February 2024.

Ironwood Pharmaceuticals, Inc.

By: /s/ Thomas Mccourt

Thomas McCourt

Chief Executive Officer

Pursuant to the requirements of Section 13 or 15(d) of the Securities Exchange Act of 1934, this report has been signed below by the following persons on behalf of the registrant and in the capacities and on the date indicated.

Signature Title Date

Thomas McCourt

Sravan K. Emany

Ronald Silver

/s/ Julie H. McHugh Chair of the Board February 16, 2024

Julie H. McHugh

/s/ Mark Currie Director February 16, 2024

Mark Currie

Director

Alexander Denner

/s/ Andrew Dreyfus Director February 16, 2024

Andrew Dreyfus

/s/ Jon Duane Director February 16, 2024

Jon Duane

/s/ Marla Kessler Director February 16, 2024

Marla Kessler

/s/ Catherine Moukheibir Director February 16, 2024

Catherine Moukheibir

/s/ Jay P. Shepard Director February 16, 2024

Jay P. Shepard

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Index to Consolidated Financial Statements of

Ironwood Pharmaceuticals, Inc.

Page

Report of Independent Registered Public Accounting Firm F-2

Consolidated Balance Sheets as of December 31, 2023 and 2022 F-4

Notes to Consolidated Financial Statements F-9

F-1

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Report of Independent Registered Public Accounting Firm

To the Stockholders and the Board of Directors of Ironwood Pharmaceuticals, Inc.

Opinion on the Financial Statements

We have audited the accompanying consolidated balance sheets of Ironwood Pharmaceuticals, Inc. (the Company) as of December 31, 2023 and 2022, the related consolidated statements of income (loss), comprehensive income (loss), stockholders' equity (deficit) and cash flows for each of the three years in the period ended December 31, 2023, and the related notes (collectively referred to as the “consolidated financial statements”). In our opinion, the consolidated financial statements present fairly, in all material respects, the financial position of the Company at December 31, 2023 and 2022, and the results of its operations and its cash flows for each of the three years in the period ended December 31, 2023, in conformity with U.S. generally accepted accounting principles.

We also have audited, in accordance with the standards of the Public Company Accounting Oversight Board (United States) (PCAOB), the Company's internal control over financial reporting as of December 31, 2023, based on criteria established in Internal Control—Integrated Framework issued by the Committee of Sponsoring Organizations of the Treadway Commission (2013 framework), and our report dated February 16, 2024 expressed an unqualified opinion thereon.

Basis for Opinion

These financial statements are the responsibility of the Company's management. Our responsibility is to express an opinion on the Company’s financial statements based on our audits. We are a public accounting firm registered with the PCAOB and are required to be independent with respect to the Company in accordance with the U.S. federal securities laws and the applicable rules and regulations of the Securities and Exchange Commission and the PCAOB.

We conducted our audits in accordance with the standards of the PCAOB. Those standards require that we plan and perform the audit to obtain reasonable assurance about whether the financial statements are free of material misstatement, whether due to error or fraud. Our audits included performing procedures to assess the risks of material misstatement of the financial statements, whether due to error or fraud, and performing procedures that respond to those risks. Such procedures included examining, on a test basis, evidence regarding the amounts and disclosures in the financial statements. Our audits also included evaluating the accounting principles used and significant estimates made by management, as well as evaluating the overall presentation of the financial statements. We believe that our audits provide a reasonable basis for our opinion.

Adoption of New Accounting Standard

As discussed in Note 2 to the consolidated financial statements, the Company changed its method of accounting for convertible senior notes in 2022 due to the adoption of ASU 2020-06.

Critical Audit Matter

The critical audit matter communicated below is a matter arising from the current period audit of the financial statements that was communicated or required to be communicated to the audit committee and that: (1) relates to accounts or disclosures that are material to the financial statements and (2) involved our especially challenging, subjective or complex judgments. The communication of the critical audit matter does not alter in any way our opinion on the consolidated financial statements, taken as a whole, and we are not, by communicating the critical audit matter below, providing a separate opinion on the critical audit matter or on the accounts or disclosures to which it relates.

Collaboration Agreement for North America with AbbVie Inc.

F-2

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/s/ Ernst & Young LLP

We have served as the Company’s auditor since 1998.

Boston, Massachusetts

February 16, 2024

F-3

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Ironwood Pharmaceuticals, Inc.

Consolidated Balance Sheets

(In thousands, except share and per share amounts)

December 31, December 31,

ASSETS

Current assets:

Prepaid expenses and other current assets 12,012 7,715

Restricted cash — 1,250

Restricted cash, net of current portion — 485

Accounts receivable, net of current portion — 14,589

Property and equipment, net 5,585 6,288

Operating lease right-of-use assets 12,586 14,023

Intangible assets, net 3,682 —

LIABILITIES AND STOCKHOLDERS' EQUITY

Current liabilities:

Accrued research and development costs 21,331 5,258

Accrued expenses and other current liabilities 44,254 16,700

Current portion of operating lease liabilities 3,126 3,065

Current portion of convertible senior notes 199,560 —

Note hedge warrants — 19

Operating lease obligations, net of current portion 14,543 16,599

Convertible senior notes, net of current portion 198,309 396,251

Revolving credit facility 300,000 —

Commitments and contingencies

Stockholders’ equity (deficit):

Accumulated other comprehensive loss (3,031) —

Total stockholders’ equity (deficit) (346,295) 652,378

Total liabilities and stockholders’ equity $ 471,073 $ 1,100,519

The accompanying notes are an integral part of these consolidated financial statements.

F-4

Table of Contents

Ironwood Pharmaceuticals, Inc.

Consolidated Statements of Income (Loss)

(In thousands, except per share amounts)

Years Ended December 31,

Revenues:

Sale of active pharmaceutical ingredient — — 969

Costs and expenses:

Restructuring expenses 18,317 — (44)

Acquired in-process research and development 1,095,449 — —

Other income (expense):

Interest expense and other financing costs (21,629) (7,598) (31,150)

IRWD US Equity

IRWD · 10-K · period ended 2023-12-31

Item 7. Management’s Discussion and Analysis of Financial Condition and Results of Operations

Item 7A. Quantitative and Qualitative Disclosures about Market Risk

Item 8. Financial Statements and Supplementary Data

Item 9. Changes in and Disagreements with Accountants on Accounting and Financial Disclosure

Item 9A. Controls and Procedures

Item 9B. Other Information

Item 10. Directors, Executive Officers and Corporate Governance

Item 11. Executive Compensation

Item 12. Security Ownership of Certain Beneficial Owners and Management and Related Stockholder Matters

Item 13. Certain Relationships and Related Transactions, and Director Independence

Item 14. Principal Accountant Fees and Services

Item 15. Exhibits and Financial Statement Schedules

Item 16. Form10-K Summary

IRWD US Equity☆

IRWD · 10-K · period ended 2023-12-31

Item 7. Management’s Discussion and Analysis of Financial Condition and Results of Operations

Item 7A. Quantitative and Qualitative Disclosures about Market Risk

Item 8. Financial Statements and Supplementary Data

Item 9. Changes in and Disagreements with Accountants on Accounting and Financial Disclosure

Item 9A. Controls and Procedures

Item 9B. Other Information

Item 10. Directors, Executive Officers and Corporate Governance

Item 11. Executive Compensation

Item 12. Security Ownership of Certain Beneficial Owners and Management and Related Stockholder Matters

Item 13. Certain Relationships and Related Transactions, and Director Independence

Item 14. Principal Accountant Fees and Services

Item 15. Exhibits and Financial Statement Schedules

Item 16. Form10-K Summary

IRWD US Equity