Ironwood Pharmaceuticals Reports Third Quarter 2024 Results - LINZESS (Iinaclotide) EUTRx prescription demand growth of 13% year-over-year - - Remains on track to complete apraglutide NDA submission

Ironwood Pharmaceuticals Reports Third Quarter

- LINZESS (Iinaclotide)

EUTRx prescription demand growth of 13% year-over-year -

- Remains on track to complete apraglutide

NDA submission in Q1 2025 -

- Maintains Full Year 2024 Financial Guidance

BOSTON, Mass., November 7, 2024 - Ironwood Pharmaceuticals, Inc.

(Nasdaq: IRWD), a GI-focused healthcare company, today reported its third quarter 2024 results and recent business performance.

"LINZESS continued to deliver robust prescription demand growth

in the third quarter," said Tom McCourt, chief executive officer of Ironwood Pharmaceuticals. "LINZESS extended units and

new-to-brand prescriptions each increased 13% year-over-year, respectively, reinforcing that patients and health care professionals continue

to choose LINZESS in a growing market. Although LINZESS has faced pricing headwinds throughout 2024, we are maintaining our full year

financial guidance. With apraglutide, we continue making progress in preparing the NDA submission and remain on track to complete the

submission in the first quarter of 2025. Our team is focused on getting apraglutide to market as soon as possible, and we look forward

to providing more updates on our progress in the months ahead. We believe that, if approved, apraglutide would be the drug of choice among

physicians to treat adult patients with short bowel syndrome who are dependent on parenteral support."

Third Quarter 2024 Financial Highlights1

(in thousands, except for per share amounts)

1 Refer to the Reconciliation of GAAP Results

to Non-GAAP Financial Measures table and to the Reconciliation of GAAP Net Income to Adjusted EBITDA table at the end of this press release.

Refer to Non-GAAP Financial Measures for additional information.

Third Quarter 2024 Corporate Highlights

Ironwood has decided to end further recruitment for the Phase

II proof of concept study in IC/BPS and analyze the data once all currently enrolled patients complete the full 12-week study assessment,

which will inform the next steps on the program.

Revolving Credit Facility

Quarter 2024 Financial Results

1 Adjusted EBITDA is calculated by subtracting restructuring

expenses, net interest expense, income taxes, depreciation and amortization, and acquisition-related costs from GAAP net income. For purposes

of the 2024 guidance, Ironwood has assumed it will not incur material expenses related to business development activities in 2024.

Ironwood does not provide guidance on GAAP net income or a reconciliation of expected adjusted EBITDA to expected GAAP net income because,

without unreasonable efforts, it is unable to predict with reasonable certainty the non-GAAP adjustments used to calculate adjusted EBITDA.

These adjustments are uncertain, depend on various factors and could have a material impact on GAAP net income for the guidance period.

Management believes this non-GAAP information is useful for investors, taken in conjunction with Ironwood's GAAP financial statements,

because it provides greater transparency and period-over-period comparability with respect to Ironwood's operating performance.

These measures are also used by management to assess the performance of the business. Investors should consider these non-GAAP measures

only as a supplement to, not as a substitute for or as superior to, measures of financial performance prepared in accordance with GAAP.

In addition, these non-GAAP financial measures are unlikely to be comparable with non-GAAP information provided by other companies.

Non-GAAP Financial Measures

Ironwood presents non-GAAP net income (loss) and non-GAAP net income

(loss) per share to exclude the impact, net of tax effects, of net gains and losses on derivatives related to Ironwood's 2022 Convertible

Notes that are required to be marked-to-market, amortization of acquired intangible assets, restructuring expenses, and acquisition-related

costs. Non-GAAP adjustments are further detailed below:

Ironwood also presents adjusted EBITDA, a non-GAAP measure, as well

as guidance on adjusted EBITDA. Adjusted EBITDA is calculated by subtracting mark-to-market adjustments on derivatives related to Ironwood's

2022 Convertible Notes, restructuring expenses, net interest expense, income taxes, depreciation and amortization, and acquisition-related

costs from GAAP net income. The adjustments are made on a similar basis as described above related to non-GAAP net income (loss), as applicable.

Management believes this non-GAAP information is useful for investors,

taken in conjunction with Ironwood's GAAP financial statements, because it provides greater transparency and period-over-period

comparability with respect to Ironwood's operating performance. These measures are also used by management to assess the performance

of the business. Investors should consider these non-GAAP measures only as a supplement to, not as a substitute for or as superior to,

measures of financial performance prepared in accordance with GAAP. In addition, these non-GAAP financial measures are unlikely to be

comparable with non-GAAP information provided by other companies. For a reconciliation of non-GAAP net income (loss) and non-GAAP net

income (loss) per share to GAAP net income and GAAP net income per share, respectively, and for a reconciliation of adjusted EBITDA to

GAAP net income, please refer to the tables at the end of this press release.

Ironwood does not provide guidance on GAAP net income or a reconciliation

of expected adjusted EBITDA to expected GAAP net income because, without unreasonable efforts, it is unable to predict with reasonable

certainty the non-GAAP adjustments used to calculate adjusted EBITDA. These adjustments are uncertain, depend on various factors

and could have a material impact on GAAP net income for the guidance period.

Conference Call Information

Ironwood will host a conference call and webcast at 8:30 a.m. Eastern

Time on Thursday, November 7, 2024 to discuss its third quarter 2024 results and recent business activities. Individuals interested

in participating in the call should dial (888) 596-4144 (U.S. and Canada) or (646) 968-2525 (international) using conference ID number

and event passcode 2530602. To access the webcast, please visit the Investors section of Ironwood's website at www.ironwoodpharma.com.

The call will be available for replay via telephone starting at approximately 11:30 a.m. Eastern Time on November 7, 2024,

running through 11:59 p.m. Eastern Time on November 21, 2024. To listen to the replay, dial (800) 770-2030 (U.S. and Canada)

or (609) 800-9909 (international) using conference ID number 2530602. The archived webcast will be available on Ironwood's website

for 1 year beginning approximately one hour after the call has completed.

About Ironwood Pharmaceuticals

Ironwood Pharmaceuticals (Nasdaq: IRWD), an S&P

SmallCap 600 company, is a leading gastrointestinal (GI) healthcare company on a mission to advance the treatment of GI diseases

and redefine the standard of care for GI patients. We are pioneers in the development of LINZESS (linaclotide), the U.S. branded

prescription market leader for adults with irritable bowel syndrome with constipation (IBS-C) or chronic idiopathic constipation (CIC).

LINZESS is also approved for the treatment of functional constipation in pediatric patients ages 6-17 years-old. Ironwood is also advancing

apraglutide, a next-generation, long-acting synthetic GLP-2 analog being developed for rare gastrointestinal diseases, including short

bowel syndrome with intestinal failure (SBS-IF) as well as several earlier stage assets. Building upon our history of GI innovation, we

keep patients at the heart of our R&D and commercialization efforts to reduce the burden of GI diseases and address significant unmet

Founded in 1998, Ironwood Pharmaceuticals

is headquartered in Boston, Massachusetts, with a site in Basel, Switzerland.

routinely post information that may be important to investors on our website at www.ironwoodpharma.com.

About LINZESS (Linaclotide)

LINZESS is the #1 prescribed brand in the U.S. for the treatment

of adult patients with irritable bowel syndrome with constipation ("IBS-C") or chronic idiopathic constipation ("CIC"),

based on IQVIA data.

LINZESS is a once-daily capsule that helps relieve the abdominal pain,

constipation, and overall abdominal symptoms of bloating, discomfort and pain associated with IBS-C, as well as the constipation, infrequent

stools, hard stools, straining, and incomplete evacuation associated with CIC. LINZESS relieves constipation in children and adolescents

aged 6 to 17 years with functional constipation. The recommended dose is 290 mcg for IBS-C patients and 145 mcg for CIC patients, with

a 72 mcg dose approved for use in CIC depending on individual patient presentation or tolerability. In children with functional constipation

aged 6 to 17 years, the recommended dose is 72 mcg.

LINZESS is not a laxative; it is the first medicine approved by the

FDA in a class called GC-C agonists. LINZESS contains a peptide called linaclotide that activates the GC-C receptor in the intestine.

Activation of GC-C is thought to result in increased intestinal fluid secretion and accelerated transit and a decrease in the activity

of pain-sensing nerves in the intestine. The clinical relevance of the effect on pain fibers, which is based on nonclinical studies, has

not been established.

In the United States, Ironwood and AbbVie co-develop and co-commercialize

LINZESS for the treatment of adults with IBS-C or CIC. In Europe, AbbVie markets linaclotide under the brand name CONSTELLA for the

treatment of adults with moderate to severe IBS-C. In Japan, Ironwood's partner, Astellas, markets linaclotide under the brand name