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UNITED STATES

SECURITIES AND EXCHANGE COMMISSION

Washington, D.C. 20549

FORM 10-K

(Mark One)

For the fiscal year ended December 31, 2020

For the transition period from to

Commission File Number 001-34620

IRONWOOD PHARMACEUTICALS, INC.

(Exact name of registrant as specified in its charter)

(617) 621-7722

(Registrant’s telephone number, including area code)

Securities registered pursuant to Section 12(b) of the Act:

Title of each class Trading Symbol(s) Name of each exchange on which registered

Class A Common Stock, $0.001 par value IRWD Nasdaq Global Select Market

Securities registered pursuant to Section 12(g) of the Act: None

Indicate by check mark if the registrant is a well-known seasoned issuer, as defined in Rule 405 of the Securities Act. Yes☒ No ☐

Indicate by check mark if the registrant is not required to file reports pursuant to Section 13 or 15(d) of the Exchange Act. Yes ☐No☒

Indicate by check mark whether the registrant: (1) has filed all reports required to be filed by Section 13 or 15(d) of the Securities Exchange Act of 1934 during the preceding 12 months (or for such shorter period that the registrant was required to file such reports) and (2) has been subject to such filing requirements for the past 90 days. Yes☒ No ☐

Indicate by check mark whether the Registrant has submitted electronically every Interactive Data File required to be submitted pursuant to Rule 405 of Regulation S-T (§232.405 of this chapter) during the preceding 12 months (or for such shorter period that the Registrant was required to submit and post such files). Yes☒ No ☐

Indicate by check mark whether the registrant is a large accelerated filer, an accelerated filer, a non-accelerated filer, a smaller reporting company, or an emerging growth company. See the definitions of “large accelerated filer,” “accelerated filer,” “smaller reporting company,” and “emerging growth company” in Rule 12b-2 of the Exchange Act.

If an emerging growth company, indicate by check mark if the registrant has elected not to use the extended transition period for complying with any new or revised financial accounting standards provided pursuant to Section 13(a) of the Exchange Act. ☐

Indicate by check mark whether the registrant has filed a report on and attestation to its management’s assessment of the effectiveness of its internal control over financial reporting under Section 404(b) of the Sarbanes-Oxley Act (15 U.S.C. 7262(b)) by the registered public accounting firm that prepared or issued its audit report. ☒

Indicate by check mark whether the registrant is a shell company (as defined in Rule 12b-2 of the Exchange Act). Yes ☐ No ☒

Aggregate market value of voting stock held by non-affiliates of the Registrant as of June 30, 2020: $1,634,804,172

As of February 10, 2021, there were 160,962,175 shares of Class A Common Stock outstanding.

DOCUMENTS INCORPORATED BY REFERENCE:

Portions of the definitive proxy statement for our 2021 Annual Meeting of Stockholders are incorporated by reference into Part III of this report.

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NOTE REGARDING FORWARD-LOOKING STATEMENTS

This Annual Report on Form 10-K, including the sections titled “Business,” “Risk Factors” and “Management’s Discussion and Analysis of Financial Condition and Results of Operations”, contains forward-looking statements. All statements contained in this Annual Report on Form 10-K other than statements of historical fact are forward-looking statements. Forward-looking statements include statements regarding our future financial position, business strategy, budgets, projected costs, plans and objectives of management for future operations. The words “may,” “continue,” “estimate,” “intend,” “plan,” “will,” “believe,” “project,” “expect,” “seek,” “anticipate,” “could,” “should,” “target,” “goal,” “potential” and similar expressions may identify forward-looking statements, but the absence of these words does not necessarily mean that a statement is not forward-looking. These forward-looking statements include, among other things, statements about:

● our plans relating to discontinuing development of IW-3718;

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● asset impairments, and the drivers thereof, and purchase commitments;

● trends and challenges in our potential markets;

● our ability to attract, motivate and retain key personnel;

● other factors discussed elsewhere in this Annual Report on Form 10-K.

Any or all of our forward-looking statements in this Annual Report on Form 10-K may turn out to be inaccurate. These forward-looking statements may be affected by inaccurate assumptions or by known or unknown risks and uncertainties, including the risks, uncertainties and assumptions identified under the heading “Risk Factors” in this Annual Report on Form 10-K. In light of these risks, uncertainties and assumptions, the forward-looking events and circumstances discussed in this Annual Report on Form 10-K may not occur as contemplated, and actual results could differ materially from those anticipated or implied by the forward-looking statements.

You should not unduly rely on these forward-looking statements, which speak only as of the date of this Annual Report on Form 10-K. Unless required by law, we undertake no obligation to publicly update or revise any forward-looking statements to reflect new information or future events or otherwise. You should, however, review the factors and risks we describe in the reports we will file from time to time with the U.S. Securities and Exchange Commission, or the SEC, after the date of this Annual Report on Form 10-K.

Summary of Risks Associated with our Business

Our business is subject to a number of risks, which are discussed more fully under the heading “Risk Factors” in this Annual Report on Form 10-K. These risks include the following:

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NOTE REGARDING TRADEMARKS

LINZESS® and CONSTELLA® are trademarks of Ironwood Pharmaceuticals, Inc. ZURAMPIC® and DUZALLO® are trademarks of AstraZeneca AB. Any other trademarks referred to in this Annual Report on Form 10-K are the property of their respective owners. All rights reserved.

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Page

PART I

Item 1. Business 5

Item 1A. Risk Factors 19

Item 1B. Unresolved Staff Comments 47

Item 2. Properties 47

Item 3. Legal Proceedings 47

Item 4. Mine Safety Disclosures 47

PART II

Item 6. Selected Financial Data 50

Item 7A. Quantitative and Qualitative Disclosures about Market Risk 73

Item 8. Financial Statements and Supplementary Data 73

Item 9A. Controls and Procedures 74

Item 9B. Other Information 76

PART III

Item 10. Directors, Executive Officers and Corporate Governance 76

Item 11. Executive Compensation 76

Item 14. Principal Accountant Fees and Services 77

PART IV

Item 15. Exhibits and Financial Statement Schedules 78

Signatures 85

Index to Consolidated Financial Statements F-1

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PART I

Item 1. Business

Our Company

We are a gastrointestinal, or 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 United States Food and Drug Administration, or U.S. FDA, in a class of GI medicines called guanylate cyclase type C agonists and is indicated for adult men and women suffering from irritable bowel syndrome with constipation, or IBS-C, or chronic idiopathic constipation, or CIC. LINZESS is available to adult men and women suffering from IBS-C or CIC in the United States, or the U.S., and Mexico and to adult men and women suffering from IBS-C in Japan and China. 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 Inc. (together with its affiliates), or AbbVie, (successor to Allergan plc (together with its affiliates), or Allergan) in the U.S. and all countries worldwide other than China (including Hong Kong and Macau) and Japan, AstraZeneca AB (together with its affiliates, or AstraZeneca) in China (including Hong Kong and Macau), and Astellas Pharma Inc., or Astellas, in Japan. We also aim to leverage our leading capabilities in GI to bring additional treatment options to GI patients; for example, we have a U.S. disease education and promotional agreement with Alnylam Pharmaceuticals, Inc., or Alnylam, for Alnylam’s GIVLAARI® (givosiran) for the treatment of acute hepatic porphyria, or AHP.

On April 1, 2019, we completed a tax-free spin-off of our soluble guanylate cyclase, or sGC, business into a separate publicly traded company, Cyclerion Therapeutics, Inc., or Cyclerion. In completing the separation of our sGC business into Cyclerion, or the Separation, we advanced our strategy to drive growth as a GI-focused healthcare company, building on our commercial success with LINZESS and advancing our GI development capabilities. In 2021, we refreshed our GI-focused strategy following our decision to discontinue our IW-3718 and MD-7246 development programs and now are focused on three core priorities: maximize LINZESS, build our innovative GI pipeline and deliver sustained profits and generate cash flow.

We were incorporated in Delaware on January 5, 1998 as Microbia, Inc. On April 7, 2008, we changed our name to Ironwood Pharmaceuticals, Inc. 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.

Performance Against 2020 Core Priorities

1. Drive LINZESS Growth

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2. Advance U.S. GI Development Portfolio

3. Deliver Sustainable Profits

Impact of the COVID-19 Pandemic on our Business

There continue to be significant uncertainties surrounding the extent and duration of the impact of the COVID-19 pandemic on our business and operations. The COVID-19 pandemic resulted in changes to our business and operations which impacted our financial condition and results of operations for the year ended December 31, 2020 and the COVID-19 pandemic may have a material adverse impact on our business and financial condition in the future. We took important actions in 2020 designed to mitigate the impacts of the COVID-19 pandemic on our business. We continue to evaluate the impact of the COVID-19 pandemic on our operating results and financial condition. The impact of COVID-19 on our business and financial condition is more fully described below in Part II, Item 7: Management's Discussion and Analysis of Financial Condition and Results of —Trends and Uncertainties.

GI Programs – IBS-C and CIC

IBS-C and CIC are chronic, functional GI disorders that afflict millions of sufferers worldwide. As many as 11.5 million adults suffer from IBS-C and as many as 28.5 million adults suffer from CIC in the U.S., according to the Lieberman GI Patient Landscape Survey performed in 2010, or the Lieberman Survey. Symptoms of IBS-C include abdominal pain, discomfort and/or bloating and constipation symptoms (e.g., incomplete evacuation, infrequent bowel movements, hard/lumpy stools), while CIC is primarily characterized by constipation symptoms. Greater than 65% of IBS-C patients suffer from bloating and/or discomfort at least one time per week, according to the Lieberman Survey.

Linaclotide—U.S. In August 2012, the U.S. FDA approved LINZESS as a once-daily treatment for adult men and women suffering from IBS-C (290 mcg dose) or CIC (145 mcg dose). We and AbbVie began commercializing

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LINZESS in the U.S. in December 2012. In January 2017, the U.S. FDA approved a 72 mcg dose of linaclotide for the treatment of adult men and women with CIC.

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

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. Clinical pediatric programs in IBS-C and functional constipation are ongoing.

Linaclotide—Global. AbbVie has rights to develop and commercialize linaclotide in all countries worldwide other than China (including Hong Kong and Macau) and Japan. In November 2012, the European Commission granted marketing authorization to CONSTELLA for the symptomatic treatment of moderate to severe IBS-C in adults. CONSTELLA is the first, and to date, only drug approved in the European Union, or E.U., for IBS-C. CONSTELLA first became commercially available in certain European countries beginning in the second quarter of 2013. AbbVie is commercializing CONSTELLA in a number of European countries, including the United Kingdom, Italy and Spain.

In December 2013 and February 2014, linaclotide was approved in Canada and Mexico, respectively, as a treatment for adult men and women suffering from IBS-C or CIC. AbbVie has exclusive rights to commercialize linaclotide in Canada as CONSTELLA and in Mexico as LINZESS. In May 2014, CONSTELLA became commercially available in Canada and in June 2014, LINZESS became commercially available in Mexico.

Astellas has rights to develop, manufacture and commercialize linaclotide in Japan. In December 2016, the Japanese Ministry of Health, Labor and Welfare approved LINZESS for the treatment of adults with IBS-C in Japan. In March 2017, Astellas began commercializing LINZESS for the treatment of adults with IBS-C in Japan. In August 2018, the Japanese Ministry of Health, Labor and Welfare approved LINZESS for the treatment of adults with chronic constipation in Japan. In September 2018, Astellas began commercializing LINZESS for the treatment of adult patients with chronic constipation in Japan.

AstraZeneca has rights to develop, manufacture and commercialize linaclotide in China (including Hong Kong and Macau). In January 2019, the Chinese National Medical Products Administration approved the marketing application for LINZESS for adults with IBS-C in China. AstraZeneca began commercializing LINZESS in China in November 2019.

IW-3300

We are also advancing IW-3300, a GC-C agonist, which is in pre-clinical development for the potential treatment of visceral pain conditions, including Interstitial Cystitis / Bladder Pain Syndrome (IC / BPS) and Endometriosis. IC/BPS affects an estimated four to 12 million Americans, according to the Interstitial Cystitis Association. An estimated four million reproductive-age women in the U.S. have diagnosed endometriosis, according to a study published in Gynecologic and Obstetric Investigation in 2017. Both diseases have a limited number of treatment options available.

Collaborations and Partnerships

As part of our GI-focused strategy, we have established development and commercial capabilities that we plan to leverage as we seek to bring multiple medicines to patients. We intend to play an active role in the development and commercialization of our products in the U.S., either independently or with partners that have strong capabilities. We also intend to establish strong global brands by out-licensing development and commercialization rights to our products in other key territories to high-performing partners. We plan to seek collaborations that increase the value of our products by providing meaningful economics and incentives for us and any potential partner. We intend to continue to expand our expertise in GI by accessing innovative externally developed products and to leverage our existing capabilities to develop and commercialize these products in the U.S.

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We have pursued a partnering strategy for commercializing linaclotide that has allowed us to focus our commercialization efforts in the U.S. and enabled partners with strong global capabilities to commercialize linaclotide in territories outside of the U.S.

The following chart shows our revenue for the U.S. and territories outside of the U.S. as a percentage of our total revenue for each of the years ended December 31, 2020, 2019, and 2018.

Year Ended December 31,

Rest of world 3.1 % 9.0 % 0.9 %

Revenue attributable to our linaclotide partnerships comprised substantially all of our revenue for each of the years indicated. Further, we currently derive a significant portion of our revenue from our LINZESS collaboration with AbbVie for the U.S. and believe that the revenues from this collaboration will continue to constitute a significant portion of our total revenue for the foreseeable future. Our revenue from our LINZESS collaboration with AbbVie for the U.S. is highly dependent on the responsiveness of patients to fill prescriptions and other factors such as wholesaler buying patterns. Our collaborative arrangements revenue outside of the U.S. has fluctuated for the years ended December 31, 2020, 2019, and 2018 based on timing of milestone and non-contingent payments. Our collaborative arrangements revenue may continue to fluctuate as a result of the timing and amount of royalties from sales of linaclotide in the markets in which it is currently approved, or any other markets where linaclotide receives approval, as well as clinical and commercial milestones received and recognized under our current and future strategic partnerships outside of the U.S.

Collaboration Agreement for North America with AbbVie

In September 2007, we entered into a collaboration agreement with AbbVie to develop and commercialize linaclotide for the treatment of IBS-C, CIC and other GI conditions in North America. Under the terms of the collaboration agreement, we and AbbVie are jointly and equally funding the development and commercialization of LINZESS in the U.S., with equal share of any profits or losses. Additionally, we granted AbbVie exclusive rights to develop and commercialize linaclotide in Canada and Mexico for which we receive royalties in the mid-teens percent on net sales in those countries. AbbVie is solely responsible for the further development, regulatory approval and commercialization of linaclotide in those countries and funding any costs.

License Agreement with AbbVie (All countries other than the countries and territories of North America, China (including Hong Kong and Macau), and Japan)

In April 2009, we entered into a license agreement with Almirall S.A., or Almirall, or the European License Agreement, to develop and commercialize linaclotide in Europe (including the Commonwealth of Independent States and Turkey) for the treatment of IBS-C, CIC and other GI conditions. In October 2015, Almirall transferred its exclusive license to develop and commercialize linaclotide in Europe to AbbVie. In January 2017, we and AbbVie entered into an amendment to the European License Agreement. The European License Agreement, as amended, extended the license to develop and commercialize linaclotide in all countries other than China (including Hong Kong and Macau), Japan, and the countries and territories of North America. We refer to the additional licensed countries as the Expanded Territory. Under the European License agreement, AbbVie is obligated to pay us (i) certain commercial milestones totaling up to $42.5 million, (ii) royalties based on sales volume in Europe, beginning in the mid-single digits percent and escalating to the upper-teens percent, and (iii) on a country-by-country and product-by-product basis in the Expanded Territory, a royalty as a percentage of net sales of products containing linaclotide as an active ingredient in the upper-single digits for five years following the first commercial sale of a linaclotide product in a country, and in the low-double digits thereafter. The royalty rate for products in the Expanded Territory will decrease, on a country-by-country basis, to the lower-single digits, or cease entirely, following the occurrence of certain events.

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License Agreement for Japan with Astellas

In November 2009, we entered into a license agreement with Astellas to develop and commercialize linaclotide for the treatment of IBS-C, CIC and other GI conditions in Japan. Pursuant to this license agreement, as amended, we were responsible for the supply of linaclotide active pharmaceutical ingredient, or API, to Astellas. On August 1, 2019, we and Astellas amended and restated the license agreement. Under the terms of the amended and restated license agreement, we are no longer responsible for the supply of linaclotide API to Astellas and Astellas is responsible for its own supply of linaclotide API in Japan. Astellas is obligated to pay royalties to us at rates beginning in the mid-single-digits percent and escalating to low-double-digits percent, based on aggregate annual net sales in Japan of products containing linaclotide API.

Collaboration Agreement for China (including Hong Kong and Macau), with AstraZeneca

In October 2012, we entered into a collaboration agreement with AstraZeneca to co-develop and co-commercialize linaclotide in China (including Hong Kong and Macau). In September 2019, we and AstraZeneca amended and restated the collaboration agreement, under which AstraZeneca obtained the exclusive right to develop, manufacture and commercialize products containing linaclotide in the territory. Under the terms of the amended and restated agreement, we transferred all manufacturing responsibilities in China (including Hong Kong and Macau) to AstraZeneca, and we are entitled to receive non-contingent payments totaling $35.0 million in three installments through 2024, of which $10.0 million was received in January 2021. In addition, AstraZeneca may be required to make milestone payments totaling up to $90.0 million contingent on the achievement of certain sales targets and is required to pay tiered royalties to us at rates beginning in the mid-single-digits percent and increasing up to twenty percent based on the aggregate annual net sales of products containing linaclotide in the territory.

Co-Promotion and Other Commercial Agreements

Disease Education and Promotional Agreement with Alnylam

In August 2019, we and Alnylam entered into a disease education and promotional agreement for Alnylam’s GIVLAARI for the treatment of AHP and in December 2020, this agreement was amended. Under the agreement, we received service fees totaling approximately $5.5 million for services rendered from the commencement of the agreement through December 31, 2020 and are eligible to receive royalties based on a percentage of net sales of GIVLAARI that are directly attributable to our promotional efforts over the term of the agreement, which is approximately three years.

Our Strategy

Our vision is to become the leading U.S. GI-focused healthcare company. To achieve this vision, we are dedicated to leveraging our development and commercial expertise to advance the treatment of GI diseases and redefine the standard of care for patients suffering from GI diseases. Our strategy is focused on three core priorities: maximize LINZESS, build our innovative GI pipeline, and deliver sustained profits and generate cash flow. Key elements of our strategy include:

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Competition

Linaclotide competes globally with certain branded and generic prescription therapies and over the counter, or OTC, products for the treatment of IBS-C and CIC, or their associated symptoms.

OTC laxatives make up the majority of the treatments in the U.S. for IBS-C and CIC, according to our internal research. LINZESS accounts for the majority of prescriptions in the U.S. for adults with IBS-C and CIC, according to 2020 data from IQVIA Inc. National Prescription Audit.

Until the launch of LINZESS, the only available branded prescription therapy for IBS-C and CIC in the U.S. was AMITIZA® (lubiprostone), which was approved for the treatment of CIC in 2006, for the treatment of IBS-C in 2008, and for the treatment of opioid induced constipation in 2013. AMITIZA is being commercialized in the U.S. by Takeda Pharmaceuticals Limited. AMITIZA also is being commercialized for the treatment of adults with CIC in certain European countries, including the United Kingdom and Switzerland by Sucampo AG, and for the treatment of chronic constipation in Japan by Mylan N.V., and an authorized generic version of AMITIZA became available in the U.S. in January 2021 and is being commercialized by Endo International plc. TRULANCE® (plecanatide) was approved in the U.S. for the treatment of CIC in adults in January 2017 and for the treatment of IBS-C in adults in January 2018 and is being commercialized in the U.S. by Bausch Health Companies. Shire plc obtained approval of MOTEGRITYTM (prucalopride) in the U.S. for the treatment of CIC in adults in December 2018. In April 2019, US WorldMeds, LLC received approval for the reintroduction of ZELNORMTM (tegaserod) in the U.S. for the treatment of IBS-C in women under the age of 65. In September 2019, Ardelyx, Inc. received approval for ISBRELATM (tenapanor) in the U.S. for the treatment of IBS-C in adults. ISBRELA is not currently commercially available.

Manufacturing and Supply

It is our objective that the supply of linaclotide be safe and effective, with redundancy built into critical steps of the supply chain, and that each of our collaboration partners are in a position to manage the supply and distribution of linaclotide in their respective territories through a combination of contract manufacturers and in-house manufacturing capabilities. Linaclotide production consists of three phases—manufacture of the API (sometimes referred to as drug substance), manufacture of finished drug product and manufacture of finished goods. We and/or our partners have commercial supply agreements with multiple third-party manufacturers for the production of linaclotide API. We believe the current commercial suppliers have the capabilities to produce linaclotide API in accordance with current good manufacturing practices, or GMP, on a sufficient scale to meet the worldwide development and commercial needs for linaclotide. The commercial suppliers of linaclotide API are subject to routine inspections by regulatory agencies worldwide and also undergo periodic audit and certification by our partners’ or our own quality department.

Each of AbbVie, Astellas and AstraZeneca is responsible for linaclotide API, finished drug product and finished goods manufacturing (including bottling and packaging) and distributing the finished goods to wholesalers in its respective territories.

Prior to linaclotide, there was no precedent for long-term room temperature shelf storage formulation for an orally dosed peptide to be produced in millions of capsules per year. Our efforts to date have led to formulations that are both cost effective and able to meet the stability requirements for commercial pharmaceutical products.

Sales and Marketing

For the foreseeable future, we intend to develop and commercialize our drugs in the U.S. alone or with partners, and expect to rely on partners to develop and commercialize our drugs in territories outside the U.S. In executing our

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strategy, our goal is to retain oversight over the worldwide development and commercialization of our products by playing an active role in their commercialization or finding partners who share our vision, values, culture and processes.

To date, we have established a high-quality commercial organization dedicated to bringing innovative, highly-valued GI healthcare solutions to our customers, including patients, payors, and healthcare providers. Our GI commercial capabilities, including marketing, patient engagement and sales, are designed to support our existing product as well as potential future internally and externally developed products.

We are also coordinating efforts with our linaclotide partners to launch and maintain an integrated, global linaclotide brand. By leveraging the knowledge base and expertise of our experienced commercial team and the insights of each of our linaclotide commercialization partners, we continually improve our collective marketing strategies.

Patents and Proprietary Rights

We actively seek to protect the proprietary technology that we consider important to our business, including pursuing patents that cover our products, compositions, and formulations, their methods of use and the processes for their manufacture, as well as any other relevant inventions and improvements that are commercially important to the development of our business. We also rely on trade secrets that may be important to the development of our business.

Our success will depend significantly on our ability to obtain and maintain patent and other proprietary protection for the technology, inventions and improvements we consider important to our business; defend our patents; preserve the confidentiality of our trade secrets; and operate without infringing the patents and proprietary rights of third parties.

The term of individual patents depends upon the legal term of the patents in the countries in which they are obtained. In most countries in which we file, the patent term is 20 years from the date of filing the non-provisional application. We expect to apply, and have applied, for patent term extension in countries where it is available.

Linaclotide Patent Portfolio

Our linaclotide patent portfolio is currently composed of 14 patents in the U.S., including 12 U.S. patents listed in the U.S. FDA publication, “Approved Drug Products with Therapeutic Equivalence Evaluations”, or the Orange Book, seven granted European patents, most of which have been validated in available European countries, ten granted Japanese patents, five granted Chinese patents, 61 issued patents in other foreign jurisdictions, and numerous pending U.S., foreign and Patent Cooperation Treaty, or PCT, patent applications. We own or jointly own all of the issued patents and pending applications.

The issued U.S. patents, which will expire between 2024 and 2033, contain claims directed to the linaclotide molecule, pharmaceutical compositions thereof, methods of using linaclotide to treat GI disorders, processes for making the molecule, and room temperature stable formulations of linaclotide and methods of use thereof. The 72 mcg, 145 mcg and 290 mcg LINZESS doses are covered by various composition of matter patents in the U.S., the latest of which expires in 2026. In addition, the commercial formulations of the 72 mcg, 145 mcg and 290 mcg LINZESS doses are covered by patents in the U.S. that expire in the early 2030s. The granted European patents, which will expire between 2024 and 2036, some of which are subject to potential patent term extension, contain claims directed to the linaclotide molecule, pharmaceutical compositions thereof, uses of linaclotide to prepare medicaments for treating GI disorders, and room temperature stable formulations of linaclotide and their use in treating IBS-C and chronic constipation. The granted Chinese patents, which will expire between 2024 and 2032, the granted Japanese patents, which will expire between 2025 and 2036, some of which are subject to granted and potential patent term extension, and the granted patents in other foreign jurisdictions, which will expire between 2024 and 2034, some of which may be subject to potential patent term extension, contain claims directed to the linaclotide molecule, pharmaceutical compositions of linaclotide for use in treating GI disorders, and room temperature stable formulations of linaclotide.

We have pending patent applications in certain countries worldwide that, if issued, will expire between 2024 and 2037 and which include claims covering the linaclotide molecule, methods of using linaclotide to treat GI disorders, the current commercial formulations of linaclotide and uses thereof to treat GI disorders.

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The patent term of a patent that covers an U.S. FDA approved drug is also eligible for patent term extension, which permits patent term extension as compensation for some of the patent term lost during the U.S. FDA regulatory review process. The Hatch Waxman Act permits a patent term extension of a single patent applicable to an approved drug for up to five years beyond the expiration of the patent but the extension cannot extend the remaining term of a patent beyond a total of 14 years from the date of product approval by the U.S. FDA. The United States Patent and Trademark Office has issued a Certificate of Patent Term Extension for U.S. Patent 7,304,036, which covers linaclotide and methods of use thereof. As a result, the patent term of this patent was extended to August 30, 2026, 14 years from the date of linaclotide’s approval by the U.S. FDA. Similar provisions are available in Europe and certain other foreign jurisdictions to extend the term of a patent that covers an approved drug. We have received patent term extensions in Japan for several of our linaclotide patents. We have also received patent term extensions, called supplementary protection certificates, for certain linaclotide patents from several national patent offices in Europe.

We and AbbVie received Notice Letters regarding ANDAs submitted to the U.S. FDA by five generic drug manufacturers requesting approval to engage in commercial manufacture, use, sale and offer for sale of linaclotide capsules, proposed generic versions of LINZESS. All five manufacturers requested approval for their 145 mcg and 290 mcg generic doses of LINZESS and two requested additional approval for their 72 mcg generic doses of LINZESS. We and AbbVie have entered into settlement agreements with all five of these generic drug manufacturers providing for licenses to market their 145 mcg and 290 mcg generic versions of LINZESS, beginning as early as March 2029 (subject to U.S. FDA Approval), unless certain limited circumstances, customary for settlement agreements of this nature, occur. In addition, we and AbbVie entered into a settlement agreement providing one generic drug manufacturer a license to market its 72 mcg generic version of LINZESS beginning in August 2030 (subject to U.S. FDA Approval), unless certain limited circumstances, customary for settlement agreements of this nature, occur.

Government Regulation

Our business is subject to government regulation in both the U.S. and in other countries. In the U.S., pharmaceutical products are subject to extensive regulation by the U.S. FDA. The Federal Food, Drug, and Cosmetic Act and other federal and state statutes and regulations, as well as similar foreign regulations, govern, among other things, the research, development, testing, manufacture, storage, recordkeeping, approval, labeling, promotion and marketing, distribution, post-marketing requirements and assessments, post-approval monitoring and reporting, sampling, and import and export of pharmaceutical products. The U.S. FDA and other regulatory authorities have very broad enforcement authority and failure to abide by applicable regulatory requirements can result in administrative or judicial sanctions being imposed on us, including warning letters, refusals of government contracts, clinical holds, civil penalties, injunctions, restitution, disgorgement of profits, recall or seizure of products, total or partial suspension of production or distribution, withdrawal of approval, refusal to approve pending applications, and civil or criminal prosecution.

U.S. FDA Approval Process

No company may market a new drug in the U.S. until it has submitted an NDA to the U.S. FDA, and the U.S. FDA has approved it. The steps required before the U.S. FDA may approve an NDA generally include:

● the submission to the U.S. FDA of an NDA;

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● U.S. FDA review and approval of the NDA.

Nonclinical tests include laboratory evaluation of the product candidate, as well as animal studies to assess the potential safety and efficacy of the product candidate. The conduct of the nonclinical tests must comply with federal regulations and requirements including GLP. We must submit the results of the nonclinical tests, together with manufacturing information, analytical data and a proposed clinical trial protocol to the U.S. FDA as part of an IND, which must become effective before we may commence human clinical trials in the U.S. The IND will automatically become effective 30 days after its receipt by the U.S. FDA, unless the U.S. FDA raises concerns or questions before that time about the conduct of the proposed trial. In such a case, we must work with the U.S. FDA to resolve any outstanding concerns before the clinical trial can proceed. We cannot be sure that submission of an IND will result in the U.S. FDA allowing clinical trials to begin, or that, once begun, issues will not arise that will cause us or the U.S. FDA to modify, suspend or terminate such trials. The study protocol and informed consent information for patients in clinical trials must also be submitted to an institutional review board, or IRB, for approval. An IRB may also require the clinical trial at the site to be halted, either temporarily or permanently, for failure to comply with the IRB requirements or if the trial has been associated with unexpected serious harm to subjects. An IRB may also impose other conditions on the trial. For studies conducted outside of the U.S., similarly, we are subject to local regulations which may differ from the U.S. and local regulations must be followed appropriately.

Clinical trials involve the administration of the product candidate to humans under the supervision of qualified investigators, generally physicians not employed by or under the trial sponsor’s control. Clinical trials are typically conducted in three sequential phases, though the phases may overlap or be combined. In Phase I, the initial introduction of the drug into healthy human subjects, the drug is usually tested for safety (adverse effects), dosage tolerance and pharmacologic action, as well as to understand how the drug is taken up by and distributed within the body. Phase II usually involves studies in a limited patient population (individuals with the disease under study) to:

● identify possible adverse effects and safety risks.

Phase III trials generally further evaluate clinical efficacy and test for safety within an expanded patient population. The conduct of clinical trials is subject to extensive regulation, including compliance with GCP regulations and guidance, and regulations designed to protect the rights and safety of subjects involved in investigations.

The U.S. FDA may order the temporary or permanent discontinuation of a clinical trial at any time or impose other sanctions if it believes that the clinical trial is not being conducted in accordance with U.S. FDA requirements or presents an unacceptable risk to the clinical trial patients. We may also suspend clinical trials at any time on various grounds.

The results of the nonclinical and clinical studies, together with other detailed information, including the manufacture and composition of the product candidate, are submitted to the U.S. FDA in the form of an NDA requesting approval to market the drug. The U.S. FDA approval of the NDA is required before marketing of the product may begin in the U.S. If the NDA contains all pertinent information and data, the U.S. FDA will “file” the application and begin review. The review process, however, may be extended by U.S. FDA requests for additional information, nonclinical or clinical studies, clarification regarding information already provided in the submission, or submission of a risk evaluation and mitigation strategy. The U.S. FDA may refer an application to an advisory committee for review, evaluation and recommendation as to whether the application should be approved. The U.S. FDA is not bound by the

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recommendations of an advisory committee, but it considers such recommendations carefully when making decisions. Before approving an NDA, the U.S. FDA will typically inspect the facilities at which the product candidate is manufactured and will not approve the product candidate unless current GMP compliance is satisfactory. The U.S. FDA also typically inspects facilities responsible for performing animal testing, as well as clinical investigators who participate in clinical trials. The U.S. FDA may refuse to approve an NDA if applicable regulatory criteria are not satisfied or may require additional testing or information. The U.S. FDA may also limit the indications for use and/or require post-marketing testing and surveillance to monitor the safety or efficacy of a product. Once granted, product approvals may be withdrawn if compliance with regulatory standards is not maintained or problems are identified following initial marketing.

The testing and approval process requires substantial time, effort and financial resources, and our product candidates may not be approved on a timely basis, if at all. The time and expense required to perform the clinical testing necessary to obtain U.S. FDA approval for regulated products can frequently exceed the time and expense of the research and development initially required to create the product. The results of nonclinical studies and initial clinical trials of our product candidates are not necessarily predictive of the results from large-scale clinical trials, and clinical trials may be subject to additional costs, delays or modifications due to a number of factors, including difficulty in obtaining enough patients, investigators or product candidate supply. Failure by us or our collaborators, licensors or licensees, including AbbVie, Astellas and AstraZeneca, to obtain, or any delay in obtaining, regulatory approvals or in complying with requirements could adversely affect commercialization and our ability to receive product or royalty revenues.

Hatch-Waxman Act

The Hatch-Waxman Act established abbreviated approval procedures for generic drugs. Approval to market and distribute these drugs is obtained by submitting an ANDA with the U.S. FDA. The application for a generic drug is “abbreviated” because it need not include nonclinical or clinical data to demonstrate safety and effectiveness and may instead rely on the U.S. FDA’s previous finding that the brand drug, or reference drug, is safe and effective. In order to obtain approval of an ANDA, an applicant must, among other things, establish that its product is bioequivalent to an existing approved drug and that it has the same active ingredient(s), strength, dosage form, and route of administration. A generic drug is considered bioequivalent to its reference drug if testing demonstrates that the rate and extent of absorption of the generic drug is not significantly different from the rate and extent of absorption of the reference drug when administered under similar experimental conditions.

The Hatch-Waxman Act also provides incentives by awarding, in certain circumstances, certain legal protections from generic competition. This protection comes in the form of a non-patent exclusivity period, during which the U.S. FDA may not accept, or approve, an application for a generic drug, whether the application for such drug is submitted through an ANDA or a through another form of application, known as a 505(b)(2) application.

The Hatch-Waxman Act grants five years of exclusivity when a company develops and gains NDA approval of a new chemical entity that has not been previously approved by the U.S. FDA. This exclusivity provides that the U.S. FDA may not accept an ANDA or 505(b)(2) application for five years after the date of approval of previously approved drug, or four years in the case of an ANDA or 505(b)(2) application that challenges a patent claiming the reference drug (see discussion below regarding Paragraph IV Certifications). The Hatch‐Waxman Act also provides three years of exclusivity for approved applications for drugs that are not new chemical entities, if the application contains the results of new clinical investigations (other than bioavailability studies) conducted or sponsored by the applicant that were essential to approval of the application. Examples of applications that may require new clinical investigations essential to approval and receive three-year exclusivity include applications for new indications, dosage forms (including new drug delivery systems), strengths, or conditions of use for an already approved product. This three‐year exclusivity period only protects against U.S. FDA approval of ANDAs and 505(b)(2) applications for generic drugs for the conditions of approval (for example, indication or dosage form) that required new clinical investigations that were essential to approval; it does not prohibit the U.S. FDA from accepting or approving ANDAs or 505(b)(2) NDAs for generic drugs that do not include such conditions of approval.

Paragraph IV Certifications. Under the Hatch‐Waxman Act, NDA applicants and NDA holders must provide information about certain patents claiming their drugs, or methods of use of the drug that is the subject of the NDA, for listing in the Orange Book. When an ANDA or 505(b)(2) application is submitted, it must contain one of several possible certifications regarding each of the patents listed in the Orange Book for the reference drug. A certification that

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a listed patent is invalid, unenforceable or will not be infringed by the sale of the proposed product is called a “Paragraph IV” certification. A certification that provides the date a listed patent will expire, but does not challenge the validity, enforceability or infringement of the patent, is called a “Paragraph III” certification. FDA can approve the ANDA or 505(b)(2) application containing the Paragraph III certification upon expiration of the patent.

Within 20 days of the acceptance by the U.S. FDA of an ANDA or 505(b)(2) application containing a Paragraph IV certification, the applicant must notify the NDA holder and patent owner that the application has been submitted, and provide the factual and legal basis for the applicant’s opinion that the patent is invalid, unenforceable, or not infringed. The NDA holder or patent holder may then initiate a patent infringement suit in response to the Paragraph IV notice. If this is done within 45 days of receiving notice of the Paragraph IV certification, a 30‐month stay of the U.S. FDA’s ability to approve the ANDA or 505(b)(2) application is triggered. The U.S. FDA may approve the proposed product before the expiration of the 30‐month stay only if a court finds the patent invalid or not infringed, and the court may shorten or lengthen the 30-month stay under certain limited circumstances.

Patent Term Extension. Under the Hatch‐Waxman Act, a portion of the patent term lost during product development and U.S. FDA review of an NDA or 505(b)(2) application is extended if approval of the application is the first permitted commercial marketing of a drug containing the active ingredient. The patent term extension period is generally one‐half the time between the effective date of the IND and the date of submission of the NDA, plus the time between the date of submission of the NDA and the date of U.S. FDA approval of the product. The maximum period of patent term extension is five years, and the patent cannot be extended to more than 14 years from the date of U.S. FDA approval of the product. Only one unexpired patent claiming the drug product, a method of using the product or a method of manufacturing the product is eligible for extension and the patent holder must apply for extension within 60 days of approval. The U.S. Patent and Trademark Office, in consultation with the U.S. FDA, reviews and approves the application for patent term extension.

Other Regulatory Requirements

After approval, finished drug products are subject to extensive continuing regulation by the U.S. FDA, which include company obligations to manufacture products in accordance with current GMP, maintain and provide to the U.S. FDA updated safety and efficacy information, report adverse experiences with the product, keep certain records and submit periodic reports, obtain U.S. FDA approval of certain manufacturing or labeling changes, and comply with U.S. FDA promotion and advertising requirements and restrictions. Failure to meet these obligations can result in various adverse consequences, both voluntary and U.S. FDA-imposed, including product recalls, withdrawal of approval, restrictions on marketing, and the imposition of civil fines and criminal penalties against the NDA holder. In addition, later discovery of previously unknown safety or efficacy issues may result in restrictions on the product, manufacturer or NDA holder.

We and our partners and any third-party manufacturers we or our partners engage are required to comply with applicable U.S. FDA manufacturing requirements contained in the U.S. FDA’s current GMP regulations. Current GMP regulations require, among other things, quality control and quality assurance as well as the corresponding maintenance of records and documentation. The manufacturing facilities for our products must meet current GMP requirements to the satisfaction of the U.S. FDA pursuant to a pre-approval inspection before we can use them to manufacture our products. We and any third-party manufacturers are also subject to periodic inspections of facilities by the U.S. FDA and other authorities, including procedures and operations used in the testing and manufacture of our products to assess our compliance with applicable regulations.

With respect to post-market product advertising and promotion, the U.S. FDA imposes a number of complex regulations on entities that advertise and promote pharmaceuticals, which include, among others, standards for direct-to-consumer advertising, prohibitions on promoting drugs for uses, conditions or diseases, or in patient populations that are not consistent with the drug’s approved labeling (known as “off-label use”), and principles governing industry-sponsored scientific and educational activities. Failure to comply with U.S. FDA requirements can have negative consequences, including adverse publicity, warning or untitled letters from the U.S. FDA, mandated corrective advertising or communications with doctors or patients, and civil or criminal penalties. Although physicians may prescribe legally available drugs for off-label uses, manufacturers may not market or promote such off-label uses.

Changes to some of the conditions established in an approved application, including changes in indications, labeling, or manufacturing processes or facilities, require submission and U.S. FDA approval of a new NDA or NDA

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supplement before the change can be implemented. An NDA supplement for a new indication typically requires clinical data similar in type and quality to the clinical data supporting the original application for the original indication, and the U.S. FDA uses similar procedures and actions in reviewing such NDA supplements as it does in reviewing NDAs.

Adverse event reporting and submission of periodic reports is required following U.S. FDA approval of an NDA. The U.S. FDA also may require post-marketing testing, known as Phase IV testing, risk evaluation and mitigation strategies, and surveillance to monitor the effects of an approved product or to place conditions on an approval that restrict the distribution or use of the product.

Outside the U.S., our and our collaborators’ abilities to market a product are contingent upon receiving marketing authorization from the appropriate regulatory authorities. The requirements governing the conduct of clinical trials, marketing authorization, pricing and reimbursement vary widely from jurisdiction to jurisdiction. At present, foreign marketing authorizations are applied for at a national level, although within the E.U. registration procedures are available to companies wishing to market a product in more than one E.U. member state. We are subject to U.S. federal and foreign anti-corruption laws. Those laws include the U.S. Foreign Corrupt Practices Act, or FCPA, which prohibits U.S. corporations and their representatives from offering, promising, authorizing, or making payments to any foreign government official, government staff member, political party or political candidate in an attempt to obtain or retain business abroad. The scope of the FCPA encompasses certain healthcare professionals in many countries. We are also subject to similar laws of other countries that have enacted anti-corruption laws and regulations.

Pricing and Reimbursement

Within the U.S., significant uncertainty exists regarding the coverage and reimbursement status of products approved by the U.S. FDA. Sales of our products depend, in part, on the extent to which our products will be covered by third-party payors, such as government health programs, commercial insurance and managed healthcare organizations. The process for determining whether a third-party payor will provide coverage for a finished drug product typically is separate from the process for setting the price of a finished drug product or for establishing the reimbursement rate that the payor will pay for the finished drug product once coverage is approved. Third-party payors may limit coverage to specific finished drug products on an approved list, also known as a formulary, which might not include all of the U.S. FDA-approved drugs for a particular indication. A decision by a third-party payor not to cover our products or to restrict coverage of our products could reduce utilization of our products. Moreover, a third-party payor’s decision to provide coverage for a finished drug product does not imply that an adequate reimbursement rate will be approved. Adequate third-party reimbursement may not be available to enable us to maintain price levels sufficient to realize an appropriate return on our investment in product development. Additionally, coverage and reimbursement for finished drug products can differ significantly from payor to payor. One third-party payor’s decision to cover a particular finished drug product or service does not ensure that other payors will also provide coverage for the medical product or service or will provide coverage at an adequate reimbursement rate.

The containment of healthcare costs has become a priority of federal and state governments, and the prices of drugs have been a focus in this effort. Federal and state governments have shown significant interest in implementing cost-containment programs, including restrictions on reimbursement and requirements for substitution of generic products. Adoption of new or enhanced cost-containment measures could limit our net revenue and results. Third party payors are increasingly challenging the prices charged for medical products and services and examining the medical necessity and cost effectiveness of medical products and services, in addition to their safety and efficacy. Restrictions in coverage or decreases in third-party reimbursement for our products could have a material adverse effect on our sales, results of operations and financial condition. We expect that the pharmaceutical industry will experience pricing pressures due to the increasing influence of managed care (and related implementation of managed care strategies to control utilization), additional federal and state legislative and regulatory proposals to regulate pricing of drugs, limit coverage of drugs or reduce reimbursement for drugs, and public scrutiny of drug pricing. While we cannot predict what executive, legislative and regulatory proposals will be adopted or other actions will occur, such events could have a material adverse effect on our business, financial condition and profitability. For additional information relating to pricing and reimbursement, see Item 1A, Risk Factors, elsewhere in this Annual Report on Form 10-K.

Sales and Marketing

The marketing and sale of pharmaceutical products are subject to comprehensive governmental regulation both within and outside the U.S.

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Within the U.S., numerous federal, state and local authorities have jurisdiction over, or enforce laws related to, such activities, including the U.S. FDA, U.S. Drug Enforcement Agency, Centers for Medicare & Medicaid Services, the U.S. Department of Health and Human Services Office of Inspector General, the U.S. Department of Justice, state Attorneys General, state departments of health and state pharmacy boards.

We are subject to the requirements of the Federal Food, Drug, and Cosmetic Act and accompanying regulations that prohibit pharmaceutical companies from promoting a drug prior to approval from the U.S. FDA and from promoting an approved drug in a manner inconsistent with the approved label.

We are also subject to various federal and state laws pertaining to health care “fraud and abuse,” including anti-kickback laws and false claims laws, for activities related to sales of any of our products or product candidates that may in the future receive marketing approval. Anti-kickback laws generally prohibit persons from soliciting, receiving or providing remuneration, directly or indirectly, to induce either the referral of an individual, for an item or service or the purchasing or ordering of a good or service, for which payment may be made under federal healthcare programs such as Medicare and Medicaid. Although the specific provisions of these laws vary, their scope is generally broad and there may not be regulations, guidance or court decisions that apply the laws to particular industry practices. False claims laws prohibit, among other things, individuals or entities from knowingly presenting, or causing to be presented, information or claims for payment from Medicare, Medicaid, or other third-party payors that are false or fraudulent. Violations of fraud and abuse laws may be punishable by criminal or civil sanctions, including fines and civil monetary penalties, and/or exclusion from federal health care programs (including Medicare and Medicaid).

Laws and regulations have been enacted by the federal government and various states to regulate the sales and marketing practices of pharmaceutical manufacturers with marketed products. The laws and regulations generally limit financial interactions between manufacturers and health care providers and/or require disclosure to the government and public of such interactions. Many of these laws and regulations contain ambiguous requirements or require administrative guidance for implementation.

Our Legacy Business

Separation

On April 1, 2019, we completed the Separation. At the time of the Separation, Cyclerion’s portfolio was comprised of several sGC stimulators, including olinciguat, a vascular sGC stimulator in Phase II development, praliciguat, a systemic sGC stimulator in Phase II development, and IW-6463, a central nervous system-penetrant sGC stimulator in Phase I development. In connection with the Separation, certain assets and liabilities related to the sGC business were transferred to Cyclerion, including various U.S. and foreign patents and Patent Cooperation Treaty patent applications. The Separation and related agreements are more fully described in Note 3, Cyclerion Separation, to our consolidated financial statements appearing elsewhere in this Annual Report on Form 10-K.

Uncontrolled Gout Programs

In June 2016, we closed a transaction with AstraZeneca pursuant to which we received an exclusive license to develop, manufacture, and commercialize in the U.S. products containing lesinurad as an active ingredient, including ZURAMPIC® and DUZALLO®. In January 2018, we commenced an initiative to evaluate the optimal mix of investments for our lesinurad franchise for uncontrolled gout, including ZURAMPIC and DUZALLO. As part of this effort, in 2018 we began re-allocating resources within our lesinurad franchise to systematically explore a more comprehensive marketing mix in select test markets (with paired controls), while continuing to build market presence for the lesinurad franchise across the country. In July 2018, we obtained and analyzed the results from the lesinurad franchise test markets. Data from the test markets did not meet expectations. In connection with the results, we determined on July 31, 2018 to terminate the lesinurad license agreement. In August 2018, we delivered to AstraZeneca a notice of termination of the lesinurad license agreement. The post-marketing clinical study to further evaluate the renal and cardiovascular safety of lesinurad was terminated following the termination of the lesinurad license agreement. We requested that the U.S. FDA withdraw approval of the NDA for the Lesinurad Products, and in January 2021, the NDA withdrawal for DUZALLO became effective.

Human Capital

As of January 1, 2021, Ironwood had 232 employees. Of these employees, 42 were on our drug development team, 128 were on our sales and commercial team, and 62 were in general and administrative functions. In connection with our decision to discontinue development of IW-3718, we reduced our workforce by approximately 100 full-time

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employees, which reduction was substantially completed in the fourth quarter of 2020. For information regarding reductions in our workforce during the years ended December 31, 2020, 2019 and 2018, refer to Note 18, Workforce Reduction and Restructuring, to our consolidated financial statements appearing elsewhere in this Annual Report on Form 10-K. We consider our employee relations to be good.

Equity, Diversity, and Inclusion (EDI)

We believe that creating an equitable, diverse, and inclusive culture is critical to attracting, motivating and retaining the talent necessary to deliver on our mission. Approximately 50% of our employees are women, and women represent approximately 30% of our leadership team (vice president and above) and nearly 30% of our board of directors (including our board and audit chairs). Additionally, approximately 20% of our employees are racially or ethnically diverse and, in 2020, approximately 40% of our new hires were racially or ethnically diverse.

In 2020, we established an EDI workgroup dedicated to advancing key EDI initiatives. Ironwood’s leadership team and board of directors champions these efforts. In October 2020, our management adopted a long-term EDI strategy and, in January 2021, our board of directors approved a specific corporate goal for 2021 aimed at fostering an environment where employees feel included and empowered. Current EDI initiatives include empowering our employee resource groups, such as Ironwomen and ISTAR (Ironwood Stands Together Against Racism), introducing new learning and development opportunities, strengthening our talent acquisition strategies, and introducing new metrics and measurements on outreach to diverse candidate sources, retention, career advancement, and employee survey feedback from diverse populations.

Compensation and Benefits

All our employees receive equity and are encouraged to think and act as owners of Ironwood. We strive to provide pay, benefits, and services that are competitive to market and to create incentives to attract, motivate and retain our employees. We are focused on pay equity and regularly monitor our pay practices among similar roles and responsibilities throughout our organization.

Communication and Engagement

We strongly believe that Ironwood’s success depends on employees understanding how their work contributes to Ironwood’s ability to execute on its vision, mission and strategy. Communication and engagement have been especially critical in 2020 in light of challenges brought on by macro events such as the COVID-19 pandemic and the racial injustice in the U.S., as well as internal factors including the recent reduction in our workforce. To this end, we utilize a variety of channels to facilitate open and direct communication, including frequent town hall meetings, Ironwood intranet, CEO blog, leadership engagement opportunities, regular communications regarding business updates, and employee engagement surveys.

Health, Wellness and Safety in the Face of the COVID-19 Pandemic

The health and safety of all our employees is a top priority for us. In 2020, we augmented certain healthcare, childcare and leave benefits in an effort to support our employees and their families in the face of the unique challenges brought on by the COVID-19 pandemic. In addition, we established a working group focused on creating and keeping employees well informed about the company’s latest plans and guidance around COVID-19. We also provided personal protective equipment and safety trainings for field-based employees, a home supply stipend to create home office space, reallocated commuter benefits for home office use, extended additional wellness benefits including backup childcare, and provided our employees with resilience training, among other efforts.

Available Information

You may obtain free copies of our Annual Reports on Form 10-K, Quarterly Reports on Form 10-Q and Current Reports on Form 8-K, and amendments to those reports, as soon as reasonably practicable after they are electronically filed or furnished to the SEC, on the Investors section of our website at www.ironwoodpharma.com or by contacting our Investor Relations department at (617) 374-5082. The contents of our website are not incorporated by reference into this report and you should not consider information provided on our website to be part of this report.

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PART II OTHER INFORMATION

Item 1A. Risk Factors

In addition to the other information in this Annual Report on Form 10-K, any of the factors described below could significantly and negatively affect our business, financial condition, results of operations or prospects. The trading price of our Class A Common Stock may decline due to these risks.

Risks Related to Commercializing LINZESS and Other Product Candidates

We are highly dependent on the commercial success of LINZESS (linaclotide) in the United States, or the U.S., for the foreseeable future; we cannot guarantee that we will generate sufficient revenues from LINZESS to cover our expenses.

We and our partner, AbbVie Inc. (together with its affiliates), or AbbVie, (successor to Allergan plc (together with its affiliates), or Allergan), began selling LINZESS in the U.S. in December 2012. Revenues from our LINZESS collaboration constitute a significant portion of our total revenue, and we believe they will continue to do so for the foreseeable future. The commercial success of LINZESS depends on a number of factors, including:

● the size of the treatable patient population;

● the effectiveness of our partners’ distribution networks;

Our revenues from the commercialization of LINZESS are subject to these and other factors, and therefore may be unpredictable from quarter-to-quarter. Revenues from LINZESS or other sources in any quarter may be insufficientto cover our expenses.

Our products may cause undesirable side effects or have other properties that could limit their commercial potential.

Linaclotide has been prescribed to millions of patients since its launch in the U.S. and other territories beginning in December 2012. The most commonly reported adverse reaction since linaclotide became commercially available, as well as in the clinical trials for linaclotide in IBS-C and CIC, has been diarrhea. In the linaclotide Phase III IBS-C and CIC trials, severe diarrhea was reported in 2% or less of the linaclotide-treated patients and its incidence was similar between the IBS-C and CIC populations.

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The number and type of patients treated with linaclotide could continue to grow if physicians prescribe linaclotide to more patients and as we and our partners conduct clinical trials, including in new indications, populations or formulations, as well as explore potential combination products, in existing and new territories. As patient experience increases and expands, we and others may identify previously unknown side effects, known side effects may be found to be more frequent and/or severe than in the past, and we and others may detect unexpected safety signals for our products or any products perceived to be similar to our products. The foregoing, or the perception of the foregoing, may have the following effects, among others:

● sales of our products may be impaired;

● our or our products’ reputation in the marketplace may suffer; and

Any of the above occurrences would harm or prevent sales of our products, increase expenses and impair our and our partners’ ability to successfully commercialize our products.

In addition, the U.S. FDA-approved label for LINZESS contains a boxed warning about its use in pediatric patients. LINZESS is contraindicated in pediatric patients up to six years of age based on nonclinical data from studies in neonatal mice approximately equivalent to human pediatric patients less than two years of age. There is also a warning advising physicians to avoid the use of LINZESS in pediatric patients six to less than 18 years of age. This warning is based on data in young juvenile mice and, at the time of approval, the lack of pediatric clinical safety and efficacy data. 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. These and other restrictions could limit the commercial potential of LINZESS.

We are subject to uncertainty relating to pricing and reimbursement policies in the U.S. which, if not favorable for our products, could hinder or prevent our products’ commercial success.

Our and our partner’s ability to commercialize our products successfully depends in part on the coverage and reimbursement levels set by governmental authorities, private health insurers and other third-party payors. In determining whether to approve reimbursement for our products and at what level, we expect that third-party payors will consider factors that include the efficacy, cost effectiveness and safety of our products, as wellas the availability of other treatments including generic prescription drugs and over-the-counter alternatives. Further, in order to obtain and maintain acceptable reimbursement levels and access for patients at copay levels that are reasonable and customary, we have offered, and expect to continue to face increasing pressure to offer, discounts or rebates from list prices ordiscounts to third-party payors or other unfavorable pricing modifications. Obtaining and maintaining favorable reimbursement can be a time consuming and expensive process, and there is no guarantee that we or AbbVie will be able to negotiate or continue to negotiate pricing terms with third-party payors at levels that are profitable to us, or at all. Certain third-party payors also require prior authorization for, or even refuse to provide, reimbursement for our products, and others may do so in the future. Our business would be materially adversely affected if we and our partners are not able to receive approval for reimbursement of our products from third-party payors on a broad, timely or satisfactory basis; if reimbursement is subject to overly broad or restrictive prior authorization requirements; or if reimbursement is not maintained at satisfactory levels or becomes subject to prior authorization. In addition, our business could be adversely

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affected if government healthcare programs, private health insurers, including managed care organizations, or other reimbursing bodies or payors limit or reduce the indications for or conditions under which our products may be reimbursed. Moreover, as discussed further below, changes in insurance coverage or reimbursement levels by governmental authorities, private health insurers and other third-party payors, or in the type of such coverage held by patients, as well as the impacts to healthcare access or administration (including, for example, limitations on medications or procedures deemed “non-essential,” reduced interaction between patients and physicians, and increased unemployment), due to the COVID-19 pandemic may materially harm our business and commercializationefforts.

We expect to experience pricing pressures in connection with the sale of our current and future products due to the healthcare reforms discussed below, as well as the trend toward initiatives aimed at reducing healthcare costs, the increasing influence of managed care, the scrutiny of pharmaceutical pricing, the ongoing debates on reducing government spending and additional legislative proposals. There has been significant scrutiny of pharmaceutical pricing and the resulting costs of pharmaceutical products that could cause significant operational and reimbursement changes for the pharmaceutical industry. There have been a number of federal and state efforts to address drug costs, which generally have focused on increasing transparency around drug costs or limiting drug prices, price increases or other related costs. For example, the Bipartisan Budget Act of 2018 contained various provisions that affect coverage and reimbursement of drugs, including an increase, which began in 2019, in the discount that manufacturers of Medicare Part D brand name drugs must provide to Medicare Part D beneficiaries during the coverage gap from 50% to 70%.

Healthcare reform efforts or any future legislation or regulatory actions aimed at controlling and reducing healthcare costs, including through measures designed to limit reimbursement, restrict access or impose unfavorable pricing modifications on pharmaceutical products, could impact our and our partners’ ability to obtain or maintain reimbursement for our products at satisfactory levels, or at all, which could materially harm our business and financial results.

We and our linaclotide partners are subject to uncertainty relating to pricing and reimbursement policies outside the U.S., as well as risks relating to the improper importation of linaclotide and sale of counterfeit versions of linaclotide. If such policies are not favorable, or if linaclotide is improperly imported or is counterfeited, our business and financial results could be adversely affected.

In some foreign countries, particularly Canada, the countries of Europe, Japan and China, the pricing and payment of prescription pharmaceuticals is subject to governmental control. In these countries, pricing negotiations with governmental authorities can take six to 12 months or longer after the receipt of regulatory approval and product launch. Reimbursement sources are different in each country, and each country may include a combination of distinct potential payors, including private insurance and governmental payors. Some countries may restrict the range of medicinal products for which their national health insurance systems provide reimbursement and control the prices of medicinal products for human use. To obtain favorable reimbursement for the indications sought or pricing approval in some countries, we and our partners may be required to conduct a clinical trial that compares the cost and clinical effectiveness of linaclotide to other available therapies. In addition, in countries in which linaclotide is the onlyapproved therapy for a particular indication, such as CONSTELLA as the only prescription product approved for thesymptomatic treatment of moderate to severe IBS-C in adults in Europe and LINZESS as the only prescription treatment approved for the treatment of adults with IBS-C in Japan, there may be disagreement as to what the most comparable product is, or if there even is one. Further, several countries have implemented government measures to either freeze or reduce pricing of pharmaceutical products. Many third-party payors and governmental authorities also consider the price for which the same product is being sold in other countries to determine their own pricing and reimbursement strategy, so if linaclotide is priced low or gets limited reimbursement in a particular country, this could result in similarly low pricing and reimbursement in other countries. If reimbursement for linaclotide is unavailable in any country in which reimbursement is sought, limited in scope or amount, or if pricing is set at or reduced to unsatisfactory levels, our and our partners’ ability to successfully commercialize linaclotide in such country would be impacted negatively. Furthermore, if these measures prevent us or any of our partners from selling linaclotide on a profitable basis in a particular country, they could prevent the commercial launch or continued sale of linaclotide in that country.

CONSTELLA was first launched in certain European countries for the symptomatic treatment of moderate to severe IBS-C in adults in the second quarter of 2013 and our partner, AbbVie, is currently commercializing CONSTELLA in a number of European countries, including the United Kingdom, Italy and Spain. LINZESS was first launched in Japan for the treatment of IBS-C in adults in the first quarter of 2017, and for the treatment of chronic constipation in adults in the third quarter of 2018, and our partner Astellas is currently commercializing LINZESS in Japan. In addition, LINZESS was first launched in China for the treatment of IBS-C in adults in November 2019, and

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our partner AstraZeneca is currently commercializing LINZESS in China (including Hong Kong and Macau). The pricing and reimbursement strategy is a key component of our partners’ commercialization plans for CONSTELLA in Europe and LINZESS in Japan and China. Our revenues may suffer if our partners are unable to successfully and timely conclude reimbursement, price approval or funding processes and market CONSTELLA in key member states of the E.U. or LINZESS in Japan or China, or if coverage and reimbursement for either CONSTELLA or LINZESS is limited or reduced. If our partners are not able to obtain or maintain coverage, pricing or reimbursement on acceptable terms or at all, or if such terms change in any countries in its territory, our partners may not be able to, or may decide not to, sell either CONSTELLA or LINZESS in such countries.

We and our partners also face the risk that linaclotide is imported or reimported into markets with relatively higher prices from markets with relatively lower prices, which would result in a decrease of sales and any payments we receive from the affected market. Additionally, third parties may illegally produce, distribute and/or sell counterfeit or otherwise unfit or adulterated versions of linaclotide. In either case, we and our partners may not be able to detect or, if detected, prevent or prohibit the sale of such products, which could result in dangerous health consequences for patients, loss of confidence in us, our partners and our products, and adverse regulatory or legal consequences. Any of the foregoing or other consequences could adversely impact our reputation, financial results and business.

We must work effectively and collaboratively with AbbVie to market and sell LINZESS in the U.S., and must adapt our commercial model and market strategy to the evolving landscape, for LINZESS to achieve its maximum commercial potential.

We are working closely with AbbVie to execute our joint commercialization plan for LINZESS. The commercialization plan includes an agreed upon marketing campaign that targets the physicians who see patients who could benefit from LINZESS treatment. Our marketing campaign also targets the adult men and women who suffer from IBS-C or CIC. Our commercialization plan also includes an integrated call plan for our sales forces in an effort to optimize the education of specific gastroenterologists and primary care physicians on whom our and AbbVie’s sales representatives call, and the frequency with which the representatives meet with them. In addition, we are advancing a hybrid (virtual and in-person) selling model and access to technologies such as telehealth in an effort to expand the commercial potential of LINZESS and our other product candidates in the U.S.

In order to optimize the commercial potential of LINZESS, we and AbbVie must execute upon this commercialization plan effectively and efficiently. In addition, we and AbbVie must continually assess, modify and adapt our commercialization plan in a coordinated and integrated fashion, including evaluating and adjusting as necessary the level and mix of marketing and promotion efforts, in response to changing business, market or other factors in order to advance the commercial potential of LINZESS. For example, the increase in virtual customer support and limitations on customer access by our customer-facing employees that was prompted by the COVID-19 pandemic contributed to our decision to make virtual promotion a more permanent component of our overall selling model and may further change our commercial model or the market strategy in the industry. Further, we and AbbVie must continue to focus and refine our marketing campaign to ensure a clear and understandable physician-patient dialogue around IBS-C, CIC and the potential for LINZESS as an appropriate therapy. In addition, we and AbbVie must provide our sales forces with the highest quality support, guidance and oversight for them to continue to effectively promote LINZESS to gastroenterologists and primary care physicians. If we and AbbVie fail to evolve with the changing commercial landscape successfully and perform these commercial functions in the highest quality manner and in accordance with our joint commercialization plan and related agreements, LINZESS will not achieve its maximum commercial potential and we may suffer financial harm. Our efforts to further target and engage adult patients with IBS-C or CIC may not effectively increase appropriate patient awareness or patient/physician dialogue and may not increase the revenues that we generate from LINZESS.

In addition, most of our customer-facing employees are engaged in in-person work practices; however, they are limited in the number of in-person details they are able to conduct due to containment and mitigation measures related to the COVID-19 pandemic. We monitor the impact of the COVID-19 pandemic in the territories where our customer-facing employees are engaged in in-person work practices, and in some cases, we have paused the in-person work practices as a result of the impact of the COVID-19 pandemic in those territories, and may do so again in the future. Customer-facing employees who are not providing in-person services continue to support their customers virtually through telephone and web-based technologies. Headquarters employees are expected to have the option to work remotely through mid-2021. We may delay, stop or otherwise limit in-person work in the future pending relevant health authority guidance and other safety considerations. The virtual support we continue to provide to customers may not be

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as effective as in-person efforts, and our in-person efforts may be limited and/or limited in their effectiveness. If this were to occur, or if we, AbbVie or any of our partners were unable to align on our strategy and development and commercial efforts as a result of the COVID-19 pandemic or otherwise, we may not be able to maintain or increase the revenues that we generate or our business may be otherwise materially harmed.

We face competition and new products may emerge that provide different or better alternatives for treatment of the conditions that our products are approved to treat.

The pharmaceutical industry and the markets in which we operate are intensely competitive. We compete in the marketing and sale of our products, the development of new products and the acquisition of rights to new products with commercial potential. Certain of our competitors have substantially greater financial, technical and human resources than us. Mergers and acquisitions in the pharmaceutical industry may result in even more resources being concentrated in our competitors and enable them to compete more effectively. Competition may also increase further as a result of advances made in the commercial applicability of technologies and greater availability of capital for investment in these fields. Additionally, new developments, including the development of other drug technologies and methods of preventing the incidence of disease, occur in the pharmaceutical and medical technology industries at a rapid pace.These developments may render our products obsolete ornoncompetitive.

Linaclotide competes with certain prescription therapies and over-the-counter products, including with products that have attained significant levels of market acceptance. The availability of prescription competitors and over-the- counter products could limit the demand, and the price we are able to charge, for LINZESS unless we are able to achieve and maintain market acceptance among the medical community and patients and differentiate LINZESS on the basis of its cost and/or actual or perceived benefits. For example, Takeda’s AMITIZA (lubiprostone) is approved by the U.S. FDA for sale in the U.S. for the treatment of IBS-C, CIC and opioid-induced constipation, and an authorized generic version of AMITIZA became available in the U.S. in January 2021 and is being commercialized by Endo International plc; Bausch Health’s TRULANCE (plecanatide) is approved by the U.S. FDA for sale in the U.S. for the treatment of adults with IBS-C and CIC; Takeda’s MOTEGRITY (prucalopride) is approved by the U.S. FDA for sale in the U.S. for the treatment of CIC in adults; and Alfasigma USA’s ZELNORM (tegaserod) is approved for sale in the U.S. for treatment of IBS-C in women under the age of 65. Over-the-counter laxatives such as MiraLAX® and DULCOLAX®, and lactulose, a prescription laxative treatment, are also available for the treatment of constipation. Additionally, we believe other companies are developing products which could compete with linaclotide, should they be approved by the U.S. FDA or foreign regulatory authorities and become commercially available. For example, although not currently commercially available, the U.S. FDA approved Ardelyx, Inc.’s IBSRELATM (tenapanor) for the treatment of IBS-C in adults. In addition, there are other compounds in late-stage development and other potential competitors that are in earlier stages of development that, if approved, may compete with linaclotide. If our current or potential competitors are successful in completing drug development for their drug candidates and obtain approval from the U.S. FDA or foreign regulatory authorities, they could limit the demand for linaclotide.

Even though LINZESS is approved by the U.S. FDA for use in adult patients, post-approval development and regulatory requirements still remain, which present additional challenges.

In August 2012, the U.S. FDA approved LINZESS as a once-daily treatment for adult men and women suffering from IBS-C or CIC. Although we and AbbVie completed additional nonclinical and clinical studies in adults that were required by the U.S. FDA in connection with the approval of LINZESS, LINZESS remains subject to ongoing

U.S. FDA requirements, including those governing the testing, manufacturing, labeling, packaging, storage, advertising, promotion, sale, distribution, recordkeeping and submission of safety and other post-market information.

LINZESS is contraindicated in pediatric patients up to six years of age based on nonclinical data from studiesin neonatal mice approximately equivalent to human pediatric patients less than two years of age. There is also a boxed warning advising physicians to avoid the use of LINZESS in pediatric patients six to less than 18 years of age. This warning is based on data in young juvenile mice and, at the time of approval, the lack of pediatric clinical safety and efficacy data. 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, and clinical pediatric programs in IBS-C and functional constipation are ongoing. Our ability to expand the indication or label information for LINZESS to pediatrics will depend on, among other things, our successful completion of pediatric clinical programs. In addition, as the holder of the approved NDA for ZURAMPIC, we are obligated to monitor and report adverse events and any failure of

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ZURAMPIC to meet the specifications in the NDA, to submit new or supplemental applications and to obtain U.S. FDA approval for certain changes, including changes to product labeling and manufacturingprocesses.

These post-approval requirements impose burdens and costs on us. Failure to effectively, appropriately and timely conduct and complete the required studies relating to our products, monitor and report adverse events and meet our other post-approval commitments would lead to negative regulatory action at the U.S. FDA, which could include withdrawal of regulatory approval of our products for their currently approved indications and patient populations.

Manufacturers of drug products and their facilities are subject to continual review and periodic inspections by the U.S. FDA and other regulatory authorities for compliance with GMP and other applicable regulations. If we or a regulatory agency discovers previously unknown problems with a product, such as adverse events of unanticipated severity or frequency, or problems with a facility where the product is manufactured, a regulatory agency may impose restrictions on that product or the manufacturer, including withdrawal of the product from the market or suspension of manufacturing. If we, our partners or the manufacturing facilities for our products fail to comply with applicable regulatory requirements, a regulatory agency may take the following actions, among others:

● issue warning letters or untitled letters;

● impose civil or criminal penalties;

● suspend or withdraw regulatory approval;

● suspend any ongoing clinical trials;

● seize or detain products or require us to initiate a product recall.

Even though linaclotide is approved for marketing in the U.S. and in a number of other countries, we or our partners may never receive approval to commercialize linaclotide in additional parts of the world.

In order to market any products outside of the countries where linaclotide is currently approved, we or our partners must comply with numerous and varying regulatory requirements of other jurisdictions regarding, among other things, safety and efficacy. Approval procedures vary among jurisdictions and can involve product testing and administrative review periods different from, and greater than, those in the U.S. and the other countries where linaclotide is approved. Potential risks include that the regulatory authorities:

● may not deem linaclotide safe and effective;

● may not approve of manufacturing processes and facilities;

● may change their approval policies or adopt new regulations.

If any of the foregoing were to occur, our receipt of regulatory approval in the applicable jurisdiction could be delayed or we may never receive approval at all. Additionally, we cannot be certain of the duration or extent to which the COVID-19 pandemic may impact operations of regulatory authorities in jurisdictions around the world, and any reduction in resources dedicated to review and approval of products in applicable jurisdictions could delay or otherwise impact approval or other regulatory decisions or actions. Further, regulatory approval in one jurisdiction does not ensure regulatory approval in another, but a failure or delay in obtaining regulatory approval in one jurisdiction may have a

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negative effect on the regulatory processes in others. If linaclotide is not approved for all indications or patient populations or with the label requested, this would limit the uses of linaclotide and have an adverse effect on its commercial potential or require costly post-marketing studies.

Risks Related to Our Growth Strategy

If we are unable to execute on our strategy to in-license or acquire externally developed products or product candidates, or engage in other transactions with value creation potential, our business and prospects would be materially adversely affected.

Our future success is largely dependent on our ability to successfully execute on our growth strategy, which includes in-licensing or otherwise acquiring the rights to externally developed gastrointestinal products or product candidates or engaging in other transactions with value creation potential. The success of this strategy depends upon our ability to identify, select and acquire promising assets, platforms or other opportunities. The process of proposing, negotiating and implementing a license or acquisition is lengthy and complex. Pursuit of external opportunities is also a highly competitive area and a number of other companies, including some with substantially greater financial, development, marketing and sales resources, may compete with us for license or acquisition opportunities. We have limited resources to identify and execute the acquisition or in-licensing of third-party products, product candidates, businesses or technologies and integrate them into our current infrastructure. Moreover, we expect to incur a variety of costs and devote resources to potential acquisitions or in-licensing opportunities that are never completed, or we may fail to realize the anticipated benefits of such efforts. If we are unable to successfully acquire the rights to additional products or product candidates on terms that we find acceptable, or at all, or execute other value creating transactions, we will remain smaller, less diversified and highly dependent on the commercial success of LINZESS, and our business and prospects would be materially and adversely affected.

In addition, such in-licenses, acquisitions or other transactions may entail numerous operational and financial risks, including:

● development, regulatory and commercialization challenges;

● exposure to unknown liabilities;

● higher than expected acquisition and integration costs;

● increased amortization expenses;

● inability to motivate key employees of any acquired businesses.

The development of product candidates in particular is a highly uncertain process, as we discuss further below. Any product candidate that we in-license or acquire may require additional development efforts prior to commercial sale, including extensive clinical testing and approval by the U.S. FDA and applicable foreign regulatory authorities. All product candidates are prone to risks of failure typical of pharmaceutical product development, including the possibility that a product candidate will not be shown to be sufficiently safe and effective for approval by regulatory authorities or competitors may develop alternatives that render our potential product candidates obsolete or less attractive. It is possible that none of the product candidates we may in-license or acquire will be approved for commercial sale or be otherwise commercially viable, which would impair our ability to grow. Furthermore, we may have little or no insight or control over the development and commercialization of any product that we in-license outside the licensed territory. If

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other licensees do not effectively develop or commercialize any such product outside the licensed territory, our reputation or the reputation of any such product may be impacted.

Our failure to successfully develop and commercialize additional product candidates or approved products would impair our ability to grow and/or adversely affect our business.

As part of our growth strategy, we intend to explore further linaclotide development opportunities. We and AbbVie are exploring development opportunities to enhance the clinical profile of LINZESS by studying linaclotide in new or existing indications, populations and formulations to assess its potential to treat various conditions. These development efforts may fail or may not increase the revenues that we generate from LINZESS. Furthermore, they may result in adverse events, or perceived adverse events, in certain patient populations that are then attributed to the currently approved patient population, which may result in adverse regulatory action at the U.S. FDA or in other

countries or harm linaclotide’s reputation in the marketplace, each of which could materially harm our revenues from linaclotide.

The strength of our company’s pipeline will depend in large part on the outcomes of studies of assets in our pipeline. We may spend several years and make significant investments in developing any current or future product candidate, and failure may occur at any point. Our product candidates must satisfy rigorous standards of safety and efficacy before they can be approved for sale by the U.S. FDA. To satisfy these standards, we must allocate resources among development programs and we must engage in costly and lengthy research and development efforts, which are subject to unanticipated delays and other significant uncertainties. Despite our efforts, our product candidates may not offer therapeutic or other improvement over existing competitive drugs, be proven safe and effective in clinical trials, or meet applicable regulatory standards. It is possible that none of the product candidates we develop will be approved for commercial sale, which would impair our ability to grow.

We have ongoing or planned nonclinical and clinical trials, including for linaclotide. Many companies in the pharmaceutical industry have suffered significant setbacks in clinical trials even after achieving promising results in earlier nonclinical or clinical trials. For example, in May 2020, we and AbbVie announced that our Phase II trial evaluating MD-7246, a delayed release formulation of linaclotide in adult patients with abdominal pain associated with irritable bowel syndrome with diarrhea, did not meet its primary or key secondary endpoints. Based on these findings, we and AbbVie have discontinued development of MD-7246. In addition, in September 2020, we announced that oneof 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. Following the assessment from an independent data monitoring committee, we unblinded the data and confirmed that IW-3718-302 did not meet the criteria, including the study’s primary endpoint of achieving a statistically significant improvement in heartburn severity. Based on these findings, we are discontinuing development ofIW-3718.

The findings from our completed nonclinical studies may not be replicated in later clinical trials, and our clinical trials may not be predictive of the results we may obtain in later-stage clinical trials or of the likelihood of regulatory approval. Results from our clinical trials and findings from our nonclinical studies could lead to abrupt changes in our development activities, including the possible limitation or cessation of development activities associated with a particular product candidate or program. Furthermore, our analysis of data obtained from nonclinical and clinical activities is subject to confirmation and interpretation by the U.S. FDA and other applicable regulatory authorities,which could delay, limit or prevent regulatory approval. The U.S. FDA or other regulatory authorities also may require additional clinical trials, which may be costly or delay, limit, prevent or otherwise impact regulatory submissionor approval. Satisfaction of U.S. FDA or other applicable regulatory requirements is costly, time-consuming, uncertain and subject to unanticipated delays.

If we are unable to successfully partner with other companies to develop and commercialize products and/or product candidates, our ability to grow would be impaired and our business would be adversely affected.

As part of our business strategy, we may partner with pharmaceutical, biotechnology or other companies to develop and commercialize products or product candidates. Although we have entered into such arrangements with respect to the development and commercialization of linaclotide worldwide, there can be no assurance that we will be able to do so in the future with respect to other products or product candidates that we either develop internally or in- license or that we will be able to gain the interest of potential partners; establish and maintain development, manufacturing, marketing, sales or distribution relationships on acceptable terms; that such relationships, if established,

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will be successful or on favorable terms; or that we will gain market acceptance for such products or product candidates. The process of proposing, negotiating and implementing a partnership arrangement is lengthy and complex. If we enter into any partnering arrangements with third parties, any revenues we receive will depend upon the efforts of such third parties. If we are unable to establish successful partnering arrangements, we may not gain access to the financial resources and industry experience necessary to develop, commercialize or successfully market our products or product candidates, may be forced to curtail, delay or stop a development program or one or more of our other development programs, delay commercialization, reduce the scope of our planned sales or marketing activities or undertake development or commercialization activities at our own expense, and therefore may be unable to generate revenue from products or product candidates or do so to their full potential.

Delays in the completion of clinical testing of any of our products or product candidates could result in increased costs and delay or limit our ability to generate revenues.

Delays in the completion of clinical testing could significantly affect our product development costs. We do not know whether planned clinical trials will be completed on schedule, if at all. The commencement and completion of clinical trials can be delayed for a number of reasons, including delays related to:

● obtaining regulatory approval to commence a clinical trial;

The COVID-19 pandemic has impacted enrollment in our clinical trials and may impact clinical trial enrollment or participation in the future, for example due to suspension of in-person procedures required for enrollment or lower or discontinued patient participation compared to pre-COVID-19 pandemic levels. Specifically, prior to our decision to discontinue development of IW-3718, the COVID-19 pandemic impacted enrollment in our Phase III clinical trials of IW-3718 for the treatment of refractory GERD. Clinical trials may also be delayed or discontinued as a result of ambiguous or negative interim results or assessments. In addition, a clinical trial may be suspended or terminated by us, an institutional review board overseeing the clinical trial at a clinical trial site (with respect to that site), the U.S. FDA,or other regulatory authorities due to a number of factors,including:

● unforeseen safety issues; or

● lack of adequate enrollment or funding to continue the clinical trial.

Additionally, changes in regulatory requirements and guidance may occur, and we may need or otherwise determine to amend clinical trial protocols to reflect these changes. Each protocol amendment would require institutional review board review and approval, which may adversely impact the costs, timing or successful completion of the associated clinical trials. If we or our partners terminate or experience delays in the completion of any clinical trials, the

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commercial prospects for our products or product candidates may be harmed, and our ability to generate product revenues will be delayed. In addition, many of the factors that cause, or lead to, a delay in the commencement or completion of clinical trials may also ultimately lead to the denial of regulatory approval.

Risks Related to Our Dependence on Third Parties

Because we work with partners to develop, manufacture and commercialize linaclotide, we are dependent upon third parties, and our and our partners’ relationships with those third parties, in our and our partners’ efforts to obtain regulatory approval for, and to commercialize, linaclotide, as well as to comply with regulatory and other obligations with respect to linaclotide.

AbbVie played a significant role in the conduct of the clinical trials for linaclotide and in the subsequent collection and analysis of data, and AbbVie holds the new drug application, or NDA, for LINZESS. In addition, we are commercializing LINZESS in the U.S. with AbbVie. AbbVie is also responsible for the development, regulatory approval and commercialization of linaclotide in countries worldwide other than Japan and China (including HongKong and Macau). AbbVie is commercializing LINZESS in Mexico and CONSTELLA in Canada, as well as commercializing CONSTELLA in certain countries in Europe. Astellas and AstraZeneca are responsible for development and commercialization of LINZESS in Japan and China (including Hong Kong and Macau), respectively. Each of our partners for linaclotide also is responsible for active pharmaceutical ingredient, or API, finished drug product and finished goods manufacturing (including bottling and packaging) for its respective territories and distributing the finished goods to wholesalers. We and/or our partners have commercial supply agreements with independent third parties to manufacture the linaclotideAPI.

The integration of our efforts with our partners’ efforts is subject to the uncertainty of the marketsfor pharmaceutical products in each partner’s respective territories, and accordingly, these relationships must evolve to meet any new challenges, including those arising out of the COVID-19 pandemic, that arise in those regions. These integrated functions may not be carried out effectively and efficiently if we fail to communicate and coordinate with our linaclotide partners, and vice versa. Our linaclotide partnering strategy imposes obligations, risks and operational requirements on us as the central node in our global network of partners. If we do not effectively communicate with each partner and ensure that the entire network is making integrated and cohesive decisions focused on the global brand for linaclotide, linaclotide will not achieve its maximum commercial potential. Further, we have limited ability to control the amount or timing of resources that our partners devote to linaclotide, particularly in light of the impact of the COVID-19 pandemic on our partners’ operations. If any of our partners fails to devote sufficient time and resources to linaclotide, or if its performance is substandard or otherwise hindered, it will delay the potential submission or approval of regulatory applications for linaclotide, as well as the manufacturing and commercialization of linaclotide in the particular territory. A material breach by any of our partners of our collaboration or license agreement with such partner, or a significant disagreement between us and a partner, could also delay the regulatory approval and commercialization of linaclotide, potentially lead to costly litigation, and could have a material adverse impact on our financial condition. Moreover, although we have non-compete restrictions in place with each of our linaclotide partners, they may have competitive products or relationships with other commercial entities, some of which may compete with us. If any of our partners competes with us or assists our competitors, it could harm our competitive position.

In addition, adverse event reporting requires significant coordination with our partners and third parties. We are the holder of the global safety database for linaclotide responsible for coordinating the safety surveillance and adverse event reporting efforts worldwide with respect to linaclotide, and each of Astellas, AstraZeneca and AbbVie is responsible for reporting adverse event information from its territory to us. An AstraZeneca partner is the holder of the global safety database for lesinurad and is responsible for coordinating the safety surveillance and adverse event reporting efforts worldwide with respect to lesinurad. If we or AstraZeneca’s partner fails to perform such activities and maintain each safety database or if such parties do not report adverse events related to such products, or fail to do so in a timely manner, we may not receive the information that we or our partners are required to report to the U.S. FDA or a foreign regulatory authority regarding such products. Furthermore, we or such parties may fail to adequately monitor, identify or investigate adverse events, or to report adverse events to the U.S. FDA or foreign regulatory authority accurately and within the prescribed timeframe. If we or such parties are unsuccessful in any of the foregoing due to poor process, execution, systems, oversight, communication, adjudication or otherwise, then we may suffer any number of consequences, including the imposition of additional restrictions on the use of such products, removal of such products from the market, criminal prosecution, the imposition of civil monetary penalties, seizure of such products, or delay in approval of future products.

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We rely entirely on contract manufacturers, our partners and other third parties to manufacture linaclotide and our other product candidates and distribute linaclotide. If they are unable to comply with applicable regulatory requirements, unable to source sufficient raw materials, experience manufacturing or distribution difficulties, or are otherwise unable to manufacture and distribute sufficient quantities to meet demand, our development and commercialization efforts may be materially harmed.

We have no internal manufacturing or distribution capabilities. Instead, we rely on a combination of contract manufacturers and our partners to manufacture API, finished drug product and finished goods for linaclotide and our other product candidates. Each of our partners for linaclotide is responsible for API, finished drug product and finished goods manufacturing (including bottling and packaging) for its respective territories and distributing the finished goods to wholesalers. Should we, or any of our partners or any third-party manufacturers we or our partners engage, experience setbacks or challenges in our manufacturing efforts, including setbacks related to the COVID-19 pandemic described further below, our development and commercialization efforts may be materially harmed. We and/or our partners have commercial supply agreements with independent third parties to manufacture linaclotide API.

Each of our partners and the third-party manufacturers we or our partners engage must comply with current good manufacturing practices, or GMP, and other stringent regulatory requirements enforced by the U.S. FDA and foreign regulatory authorities in other jurisdictions. These requirements include, among other things, quality control, quality assurance and the maintenance of records and documentation, which occur in addition to our and our partners’ own quality assurance releases. Manufacturers of our products may be unable to comply with these GMP requirements and with other regulatory requirements. We have little control over compliance with these regulations and standardsby our partners and the third-party manufacturers we or our partnersengage.

Our partners and the third-party manufacturers we or our partners engage may experience problems withtheir respective manufacturing and distribution operations and processes, including, for example, quality issues, such as product specification and stability failures, procedural deviations, improper equipment installation or operation, utility failures, contamination, natural disasters and public health epidemics, including the COVID-19 pandemic. In addition, the raw materials necessary to make API for our products and product candidates are acquired from a limited number of sources. Any delay or disruption in the availability of raw materials or a change in raw material suppliers could result in production disruptions, delays or higher costs with consequent adverse effects onus.

The manufacture of pharmaceutical products requires significant expertise and capital investment, including the development of advanced manufacturing techniques and process controls. Manufacturers of pharmaceutical products often encounter difficulties in commercial production. These problems include difficulties with production costs and yields, quality control, including stability of the product and quality assurance testing, and shortages of qualified personnel, as well as compliance with federal, state and foreign regulations and the challenges associated with complex supply chain management. Even if our partners or the third-party manufacturers we or our partners engage do not experience problems and commercial manufacturing is achieved, their maximum or available manufacturing capacities may be insufficient to meet commercial demand. Finding alternative manufacturers or adding additional manufacturers requires a significant amount of time and involves significant expense. New manufacturers would need to develop and implement the necessary production techniques and processes, which along with their facilities, would need to be inspected and approved by the regulatory authorities in each applicable territory.

If our partners or the third-party manufacturers we or our partners engage fail to adhere to applicable GMP or other regulatory requirements, experience delays or disruptions in the availability of raw materials or experience manufacturing or distribution problems, we will suffer significant consequences, including product seizures or recalls, loss of product approval, fines and sanctions, reputational damage, shipment delays, inventory shortages, inventory write-offs and other product-related charges and increased manufacturing costs. If we experience any of these results, or if maximum or available manufacturing capacities are insufficient to meet demand, our and our partners’ development or commercialization efforts may be materially harmed.

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If any of our linaclotide partners undergoes a change of control or in management, this may adversely affect our collaborative relationship or the success of the commercialization of linaclotide in the U.S. or in the other countries where it is approved, or the ability to achieve regulatory approval, launch and commercialize linaclotide in other territories.

We work jointly and collaboratively with partners on many aspects of the development, manufacturing and/or commercialization of linaclotide. In doing so, we have established relationships with several key members of the management teams of our linaclotide partners in functional areas such as development, quality, regulatory, drug safety and pharmacovigilance, operations, marketing, sales, field operations and medical science. Further, the success of our collaborations is highly dependent on the resources, efforts and skills of our partners and their key employees. As we and our partners develop and commercialize linaclotide in the U.S. and the other countries where it is approved, and develop, launch and commercialize linaclotide in other parts of the world, the drug’s success becomes more dependent on us maintaining highly collaborative and well aligned partnerships. In May 2020, AbbVie announced the completion of its acquisition of Allergan. Our collaboration, now with AbbVie, for the development and commercialization of linaclotide in North America, and our license, now to AbbVie, to develop and commercialize linaclotide in all countries worldwide other than China (including Hong Kong and Macau) and Japan, remain in effect. In connection with this transaction, we continue to engage with AbbVie to reestablish relationships and confirm alignment, including on our development and commercialization strategy for linaclotide. Any failure to do so could adversely affect the development and commercialization of linaclotide. If any of our linaclotide partners undergoes a change of control or in management, we would similarly need to reestablish many relationships and confirm alignment, including on our development and commercialization strategy for linaclotide. Further, in connection with any change of control or change in management, there is inherent uncertainty and disruption in operations, which could result in distraction, inefficiencies, and misalignment of priorities. As a result, in the event of a change of control or in management at one of our linaclotide partners, we cannot be sure that we will be able to successfully execute on our development and commercialization strategy for linaclotide in an effective and efficient manner and without disruption or reduced performance. Finally, any change of control or in management may result in a reprioritization of linaclotide within a partner’s portfolio, or such partner may fail to maintain the financial or other resources necessary to continue supporting its portion of the development, manufacturing or commercialization of linaclotide.

If any of our linaclotide partners undergoes a change of control and the acquirer either (i) is unable to perform such partner’s obligations under its collaboration or license agreement with us or (ii) does not comply with the divestiture or certain other provisions of the applicable agreement, we have the right to terminate the collaboration or license agreement and reacquire that partner’s rights with respect to linaclotide. If we elect to exercise these rights in such circumstances, we will need to either establish the capability to develop, manufacture and commercialize linaclotide in that partnered territory on our own or we will need to establish a relationship with a new partner. We have assembled a team that represents the functional areas necessary to support the commercialization of LINZESS in the U.S. If AbbVie was subject to a change of control that allowed us to further commercialize LINZESS in the U.S. on our own, and we chose to do so, we would need to enhance each of these functional aspects, as well as develop others, to replace the capabilities that AbbVie was previously providing to the collaboration. Any such transition might result in a period of reduced efficiency or performance by our operations and commercialization teams, which could adversely affect our ability to commercialize LINZESS.

We do not have certain operational capabilities outside of the U.S. If AbbVie, Astellas Pharma, Inc., or Astellas, or AstraZeneca AB (together with its affiliates), or AstraZeneca, was subject to a change of control that allowed us to continue linaclotide’s development or commercialization anywhere outside of the U.S. on our own, and we chose to do so rather than establishing a relationship with a new partner, we would need to build operational capabilities in the relevant territory. In any of these situations, the development and commercialization of linaclotide could be negatively impacted.

Risks Related to Regulatory, Legal and Compliance Matters

We face potential product liability exposure, and, if claims brought against us are successful, we could incur substantial liabilities.

The use of our product candidates in clinical trials and the sale of our approved products, including the sale of linaclotide and lesinurad, expose us to product liability claims. If we do not successfully defend ourselves against

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product liability claims, we could incur substantial liabilities. In addition, regardless of merit or eventual outcome, product liability claims may result in:

● decreased demand for approved products;

● impairment of our business reputation;

● withdrawal of clinical trial participants;

● initiation of investigations by regulators;

● litigation costs;

● distraction of management’s attention from our primary business;

● substantial monetary awards to patients or other claimants;

● loss of revenues; and

● the inability to commercialize our product candidates.

We currently have product liability insurance coverage for the commercial sale of our products and for the clinical trials of our product candidates which is subject to industry-standard terms, conditions and exclusions. Our insurance coverage may not be sufficient to reimburse us for expenses or losses associated with claims. Moreover, insurance coverage is becoming increasingly expensive, and, in the future, we may not be able to maintain insurance coverage at a reasonable cost or in sufficient amounts to protect us against losses. On occasion, large judgments have been awarded in lawsuits based on drugs that had unanticipated side effects. A successful product liability claim or series of claims could cause our stock price to decline and, if judgments exceed our insurance coverage, could decrease our cash and adversely affect our business.

We will incur significant liability if it is determined that we are promoting any “off-label” uses of our products.

Physicians are permitted to prescribe drug products and medical devices for uses that are not described in the product’s labeling and that differ from those approved by the U.S. FDA or other applicable regulatory agencies. Such “off-label” uses are common across medical specialties. Although the U.S. FDA and other regulatory agencies do not regulate a physician’s choice of treatments, the U.S. FDA and other regulatory agencies do restrict manufacturer

communications on off-label use. Companies are not permitted to promote drugs or medical devices for off-label uses or to promote unapproved drugs or medical devices. Accordingly, we do not permit promotion of any product that we develop, license, commercialize, promote, co-promote or otherwise partner prior to approval or for any indication, population or use not described in or consistent with such product’s label. The U.S. FDA and other regulatory and enforcement authorities actively enforce laws and regulations prohibiting promotion of off-label uses and the promotion of products for which marketing approval has not been obtained. A company that is found to have promoted off-label uses will be subject to significant liability, including civil and administrative remedies as well as criminal sanctions.

Even if it is later determined that we were not in violation of these laws, we may be faced with negative publicity, incur significant expenses defending our actions and have to divert significant management resources from other matters.

Notwithstanding the regulatory restrictions on off-label promotion, the U.S. FDA and other regulatory authorities allow companies to engage in truthful, non-misleading, and non-promotional scientific exchange concerning their products. We intend to engage in medical education activities and communicate with healthcare providers in compliance with all applicable laws, regulatory guidance and industry best practices. Although we believe we have put in place a robust compliance program, which is designed to ensure that all such activities are performed in a legal and compliant manner, we cannot be certain that our program will address all areas of potential exposure and the risks in this area cannot be entirely eliminated.

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If we fail to comply with healthcare and other regulations, we could face substantial penalties and our business, operations and financial condition could be adversely affected.

The products that we promote are marketed in the U.S. and/or covered by federal healthcare programs, and, as a result, certain federal and state healthcare laws and regulations pertaining to product promotion, fraud and abuse, privacy and price reporting and payment are applicable to, and may affect, our business. These laws and regulations include:

Our global activities are subject to the U.S. Foreign Corrupt Practices Act which prohibits corporations and individuals from paying, offering to pay, or authorizing the payment of anything of value to any foreign government official, government staff member, political party, or political candidate in an attempt to obtain or retain business or to otherwise influence a person working in an official capacity. We are also subject to similar anti-bribery laws in the other countries in which we do business.

In addition, we may be subject to privacy and security laws in the various jurisdictions in which we operate, obtain or store personally identifiable information. The legislative and regulatory landscape for privacy and data protection continues to evolve, and there has been an increasing focus on privacy and data protection issues with the potential to affect our business. For example, the processing of personal data in the European Economic Area, or the EEA, is subject to the General Data Protection Regulation, or the GDPR, which took effect in May 2018. The GDPR increases obligations with respect to clinical trials conducted in the EEA, such as in relation to the provision of fair processing notices, exercising data subject rights and reporting certain data breaches to regulators and affected

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individuals, as well as how we document our relationships with third parties that process GDPR-covered personal data on our behalf. The GDPR also increases the scrutiny applied to transfers of personal data from the EEA (including from clinical trial sites in the EEA) to countries that are considered by the European Commission to lack an adequate level of data protection, such as the United States. The July 2020 invalidation of the EU-U.S. Privacy Shield framework also may lead to increased scrutiny on data transfers from the EEA to the United States generally and increase our costs of compliance with data privacy legislation. In addition, we are subject to the California Consumer Privacy Act, or CCPA, which became effective on January 1, 2020. The CCPA gives California consumers (defined to include all California residents) certain rights, including the right to ask companies to disclose the types of personal information collected, specific pieces of information collected by a company, the categories of sources from which such information was collected, the business purpose for collecting or selling the consumer’s personal information, and the categories of third parties with whom a company shares personal information. The CCPA also imposes several obligations on companies to provide notice to California consumers regarding a company’s data processing activities. Additionally, the CCPA gives California consumers the right to ask companies to delete a consumer’s personal information and it places limitations on a company’s ability to sell personal information, including providing consumers a right to opt out of sales of their personal information. The compliance obligations imposed by the GDPR and the CCPA have required us to revise our operations. In addition, the GDPR and the CCPA impose substantial fines and other regulatory penalties for breaches of data protection requirements, and they confer a private right of action on data subjects (in the case of the GDPR) and consumers (in the case of the CCPA) and their representatives for breaches of certain data protection requirements.

If our operations are found to be in violation of any of the laws described above or any other laws, rules or regulations that apply to us, we will be subject to penalties, including civil and criminal penalties, damages, fines and the curtailment or restructuring of our operations. Any penalties, damages, fines, curtailment or restructuring of our operations could adversely affect our ability to operate our business and our financial results. Although compliance programs can mitigate the risk of investigation and prosecution for violations of these laws, rules or regulations, we cannot be certain that our program will address all areas of potential exposure and the risks in this area cannot be entirely eliminated, particularly because the requirements and government interpretations of the requirements in this space are constantly evolving. Any action against us for violation of these laws, rules or regulations, even if we successfully

defend against it, could cause us to incur significant legal expenses and divert our management’s attention from the operation of our business, as well as damage our business or reputation. Moreover, achieving and sustaining compliance with applicable federal and state privacy, security, fraud and reporting laws may prove costly.

Healthcare reform and other governmental and private payor initiatives may have an adverse effect upon, and could prevent, our products’ or product candidates’ commercial success.

The U.S. government and individual states have been aggressively pursuing healthcare reform designed to impact delivery of, and/or payment for, healthcare, which include initiatives intended to reduce the cost of healthcare. For example, in March 2010, the U.S. Congress enacted the Patient Protection and Affordable Care Act, as modified by the Health Care and Education Reconciliation Act, or the ACA, which, among other things, expanded healthcare coverage through Medicaid expansion and the implementation of the individual health insurance mandate; included changes to the coverage and reimbursement of drug products under government healthcare programs; imposed an annual fee on manufacturers of branded drugs; and expanded government enforcement authority. We face uncertainties because there have been, and may be additional, federal legislative and administrative efforts to repeal, substantially modify or invalidate some or all of the provisions of the ACA. Such efforts may lead to fewer Americans having more comprehensive health insurance compliant with the ACA, even in the absence of a legislative repeal. For example, tax reform legislation was enacted at the end of 2017 that eliminated the tax penalty for individuals who do not maintain sufficient health insurance coverage beginning in 2019. The ACA has also been subject to judicial challenge. The case Texas v. Azar, which challenges the constitutionality of the ACA, including provisions that are unrelated to healthcare reform but were enacted as part of the ACA, was argued before the Supreme Court in November 2020. Pending resolution of the litigation, all of the ACA but the individual mandate to buy health insurance remains in effect. Additional healthcare reform efforts have sought to address certain issues related to the COVID-19 pandemic, including an expansion of telehealth coverage under Medicare and accelerated or advanced Medicare payments to healthcare providers. In addition, in 2020 and 2021, the U.S. Department of Health and Human Services issued various rules that affect pricing or payment for prescription drug products. For example, effective in 2022, revisions to the federal anti-kickback statute would remove protection for traditional Medicare Part D discounts offered by pharmaceutical manufacturers to pharmacy benefit managers and health plans. Healthcare reform efforts have been and may continue to be subject to legal challenge. For example, courts have temporarily enjoined a new “most favored nation” payment model for select drugs covered under Medicare Part B that was to take effect on January 1, 2021 and would limit

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payment based on international drug price. Adoption of new healthcare reform legislation at the federal or state level could affect demand for, or pricing of, our products or product candidates if approved for sale. We cannot predict, however, the ultimate content, timing or effect of any healthcare reform legislation or action, or its impact on us, and healthcare reform could increase compliance costs and may adversely affect our future business and financial results.

In addition, other legislative changes have been adopted that could have an adverse effect upon, and could prevent, our products’ or product candidates’ commercial success. More broadly, the Budget Control Act of 2011, as amended, or the Budget Control Act, includes provisions intended to reduce the federal deficit, including reductions in Medicare payments to providers through 2030 (except May 1, 2020 to March 31, 2021). Any significant spending reductions affecting Medicare, Medicaid or other publicly funded or subsidized health programs, or any significant taxes or fees imposed as part of any broader deficit reduction effort or legislative replacement to the Budget Control Act, or otherwise, could have an adverse impact on our anticipated product revenues.

In addition to governmental efforts in the U.S., foreign jurisdictions as well as private health insurers and managed care plans are likely to continue challenging manufacturers’ ability to obtain reimbursement, as well as the level of reimbursement, for pharmaceuticals and other healthcare-related products and services. These cost-control initiatives could significantly decrease the available coverage and the price we might establish for our products, which would have an adverse effect on our financial results.

The Food and Drug Administration Amendments Act of 2007 also provides the U.S. FDA enhanced post- marketing authority, including the authority to require post-marketing studies and clinical trials, labeling changes based on new safety information, and compliance with risk evaluation and mitigation strategies approved by the U.S. FDA. 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 pediatrics. The U.S. FDA’s exercise of this authority has resulted (and is expected to continue to result) in increased development-related costs following the commercial launch of our products, and could result in potential restrictions on the sale and/or distribution of our products, even in such products’ approved indications and patient populations.

Risks Related to the Separation of Cyclerion

We may incur operational difficulties or be exposed to claims and liabilities as a result of the separation of Cyclerion.

On April 1, 2019, we distributed all of the outstanding shares of Cyclerion Therapeutics, Inc., or Cyclerion, common stock to Ironwood stockholders in connection with the separation of our soluble guanylate cyclase business, or the Separation. In connection with the distribution, we entered into a separation agreement and various other agreements (including a tax matters agreement, an employee matters agreement, transition services agreements, an intellectual property license agreement and a development agreement). These agreements govern the separation and distribution and the relationship between us and Cyclerion going forward, including with respect to potential tax-related losses associated with the separation and distribution. In addition, the development agreement provides for the performance of services by Cyclerion for our benefit for a period of time. If Cyclerion is unable to satisfy its obligations under these agreements, we could incur losses or operational challenges or difficulties and may not have sufficient resources available for such services. These arrangements could also lead to disputes over rights to certain shared property and over the allocation of costs for products and operations.

The separation agreement provides for indemnification obligations designed to make Cyclerion financially responsible for many liabilities that may exist relating to its business activities, whether incurred prior to or after the distribution, including any pending or future litigation, but we cannot guarantee that Cyclerion will be able to satisfy its indemnification obligations. It is also possible that a court would disregard the allocation agreed to between us and Cyclerion and require us to assume responsibility for obligations allocated to Cyclerion. Third parties could also seek to hold us responsible for any of these liabilities or obligations, and the indemnity rights we have under the separation agreement may not be sufficient to fully cover all of these liabilities and obligations. Even if we are successful in obtaining indemnification, we may have to bear costs temporarily. In addition, our indemnity obligations to Cyclerion, including those related to assets or liabilities allocated to us, may be significant. These risks could negatively affect our business, financial condition or results of operations.

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If the distribution of the shares of Cyclerion common stock in connection with the Separation is not generally tax- free for U.S. federal income tax purposes, we and our stockholders could be subject to significant tax liabilities.

The distribution, together with certain related transactions, is intended to qualify for tax-free treatment to usand our stockholders for U.S. federal income tax purposes. We received a favorable private letter ruling from the Internal Revenue Service, or IRS, under the pilot program established in Revenue Procedure 2017-52 relating to the U.S. federal income tax treatment of the distribution. Consistent with the guidelines set forth in Revenue Procedure 2017-52, the IRS private letter ruling does not cover all of the issues that are relevant to determining whether the distribution is generally tax free for U.S. federal income tax purposes. Accordingly, completion of the distribution was conditioned upon, among other things, our receipt of an opinion from an outside tax advisor that the distribution will qualify as a transaction thatis generally tax-free to both us and our stockholders for U.S. federal income tax purposes under Sections 355 and 368(a)(1)(D) of the Internal Revenue Code. The private letter ruling and opinion were based on and relied on, among other things, certain facts and assumptions, as well as certain representations, statements and undertakings from us and Cyclerion (including those relating to the past and future conduct of us and Cyclerion). If any of these facts, assumptions, representations, statements or undertakings is, or becomes, inaccurate or incomplete, or if we or Cyclerion breach any of our respective covenants relating to the distribution, the IRS private letter ruling and any tax opinion may be invalid. Moreover, the opinion is not binding on the IRS or any courts. Accordingly, notwithstanding receipt of the IRS private letter ruling and the opinion, the IRS could determine that the distribution and certain related transactions should be treated as taxable transactions for U.S. federal income taxpurposes.

If the distribution, together with certain related transactions, fails to qualify as a transaction that is generally tax-free under Sections 355 and 368(a)(1)(D) of the Internal Revenue Code, in general, for U.S. federal income tax purposes, we would recognize taxable gain with respect to Cyclerion’s distributed common stock and our stockholders who received shares of Cyclerion common stock in the distribution would be subject to tax as if they had received a taxable distribution equal to the fair market value of such shares.

We may not achieve some or all of the anticipated benefits of the Separation, which may adversely affect our business.

We may not be able to achieve the full strategic, financial or other benefits expected to result from the Separation, or such benefits may be delayed or not occur at all. If we fail to achieve some or all of the expected benefits of the Separation, or if such benefits are delayed, our business, financial condition, results of operations and the value of our stock could be adversely impacted. The combined value of the common stock of the two publicly traded companies may not be equal to or greater than what the value of our Class A Common Stock would have been had the Separation not occurred. In addition, we are smaller and less diversified, with a narrower business focus, than we were before the Separation and therefore may be more vulnerable to changing market conditions.

Risks Related to Intellectual Property

Limitations on our ability to obtain patent protection and/or the patent rights relating to our products and our product candidates may limit our ability to prevent third parties from competing against us.

Our success depends on our ability to obtain and maintain sufficient patent protection for our products and product candidates, preserve our trade secrets, prevent third parties from infringing upon our proprietary rights and operate without infringing upon the proprietary rights of others.

The strength of patents in the pharmaceutical industry involves complex legal and scientific questions and can be uncertain. Patent applications in the U.S. and most other countries are confidential for a period of time until they are published, and publication of discoveries in scientific or patent literature typically lags actual discoveries by several months or more. As a result, we cannot be certain that we were the first to conceive inventions covered by our patents and pending patent applications or that we were the first to file patent applications for such inventions. In addition, we cannot be certain that our patent applications will be granted, that any issued patents will adequately protect our intellectual property, or that such patents will not be challenged, narrowed, invalidated or circumvented.

We have several issued patents in the U.S. related to LINZESS, including a LINZESS composition of matter and methods of use patent (U.S. Patent 7,304,036) expiring in 2026. Additional U.S. patents related to LINZESS include multiple patents relating to our commercial, room temperature stable formulations of the 72 mcg, 145 mcg and 290 mcg

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doses of linaclotide and methods of using these formulations, the latest of which expires in the early 2030s, as well as other patents covering processes for making LINZESS, formulations thereof, and molecules related to LINZESS. Although none of these issued patents currently is subject to a patent reexamination or review, we cannot guarantee that they will not be subject to reexamination or review by the U.S. Patent and Trademark Office, or the USPTO, in the future. In addition, we have several pending patent applications in the U.S. We believe in the strength of our LINZESS patent portfolio and that we have sufficient freedom to operate; however, if any of our present or future patents is challenged, narrowed, invalidated or circumvented, or our pending patent applications are not granted, our ability to prevent third parties from competing with LINZESS could be limited and our business and financial results may be materially harmed.

Furthermore, the America Invents Act, which was signed into law in 2011, has made several major changes in the U.S. patent statutes. These changes permit third parties to challenge our patents more easily and create uncertainty with respect to the interpretation and practice of U.S. patent law. Moreover, the U.S. Supreme Court has ruled on several patent cases that narrow the scope of patent protection available and weakening the rights of patent owners in certain circumstances. Depending on the impact of these decisions and other actions by the U.S. Congress, the federal courts, the USPTO, and their foreign counterparts, the laws and regulations governing patents may change, or their interpretation or implementation may change, in unpredictable ways that could impact, potentially adversely, ourability to obtain new patents or to enforce and defend patents that we have already obtained or that we might obtain in the future. For example, such changes may increase the costs and complexity associated with obtaining, enforcing or defending our patents, including in abbreviated new drug application, or ANDA,litigation.

We also rely upon unpatented trade secrets, unpatented know-how and continuing technological innovation to develop and maintain our competitive position, which we seek to protect, in part, by confidentiality agreements withour employees and our partners and consultants. We also have agreements with our employees and selected consultants that obligate them to assign their inventions to us. It is possible, however, that technology relevant to our business will be independently developed by a person that is not a party to such an agreement. Furthermore, if the employees and consultants that are parties to these agreements breach or violate the terms of these agreements, we may not have adequate remedies, and we could lose our trade secrets through such breaches or violations. Additionally, our trade secrets could otherwise become known or be independently discovered by ourcompetitors.

IRWD US Equity

IRWD · 10-K · period ended 2020-12-31

Item 1. Business

Item 1A. Risk Factors

IRWD US Equity☆

IRWD · 10-K · period ended 2020-12-31

Item 1. Business

Item 1A. Risk Factors

IRWD US Equity