8-K

UNITED STATES

SECURITIES AND EXCHANGE COMMISSION

Washington, D.C. 20549

FORM 8-K

Current Report Pursuant to

Section 13 or 15(d) of the

Securities Exchange Act of 1934

Date of Report (Date of Earliest Event Reported):

June 2, 2016

IRONWOOD PHARMACEUTICALS, INC.

(Exact name of registrant as specified in its charter)

Delaware	001-34620	04-3404176
(State or other jurisdiction of incorporation)	(Commission file number)	(I.R.S. Employer Identification Number)

301 Binney Street Cambridge, Massachusetts	02142
(Address of principal executive offices)	(Zip code)

(617) 621-7722

(Registrant’s telephone number,

including area code)

Check the appropriate box below if the Form 8-K filing is intended to simultaneously satisfy the filing obligation of the registrant under any of the following provisions:

o  Written communications pursuant to Rule 425 under the Securities Act (17 CFR 230.425)

o  Soliciting material pursuant to Rule 14a-12 under the Exchange Act (17 CFR 240.14a-12)

o  Pre-commencement communications pursuant to Rule 14d-2(b) under the Exchange Act (17 CFR 240.14d-2(b))

o  Pre-commencement communications pursuant to Rule 13e-4(c) under the Exchange Act (17 CFR 240.13e-4(c))

Item 2.01 Completion of Acquisition or Disposition of Assets

On June 2, 2016 (the “Effective Date”), Ironwood Pharmaceuticals, Inc. (“Ironwood”) closed its previously announced transaction with Ardea Biosciences, Inc. (“Ardea”), an indirect wholly owned subsidiary of AstraZeneca PLC.  On April 26, 2016 (the “Execution Date”), Ironwood and Ardea entered into a license agreement (the “License Agreement”) pursuant to which Ardea granted to Ironwood a license for the commercialization, and the development, manufacture and support of such commercialization, of products containing lesinurad as an active ingredient, including Zurampic® (the “Products”), in the United States.  Subject to the terms of the License Agreement, Ardea will conduct certain development activities on Ironwood’s behalf for (i) Zurampic (including the post-marketing requirement activities currently required by the Food and Drug Administration, for which Ironwood will reimburse Ardea up to $100 million over up to ten years), and (ii) a fixed dose combination product with lesinurad and allopurinol as active ingredients, for which Ironwood will reimburse Ardea up to specified limits.  Ironwood is responsible for any additional development of the Products for commercialization in the United States and for commercialization of the Products in the United States.  In addition, under the terms of the License Agreement, Ironwood has the right of first negotiation and a right of last refusal with Ardea for the right to commercialize (and develop and manufacture for commercialization) products comprising verinurad as at least one of its active ingredients for the prevention or treatment of gout in the United States.

Pursuant to the terms of the License Agreement, Ironwood will make an upfront payment of $100 million to Ardea within ten business days of the Effective Date, and will pay a royalty to Ardea in the single digits as a percentage of net sales of the Products in the United States (such royalty rate to be dependent on the aggregate net sales of the Products). Ardea is also eligible to receive $15 million following approval of the new drug application for the fixed dose combination product with lesinurad and allopurinol as active ingredients, as well as up to an aggregate of $150 million in additional commercial milestone payments over the term of the License Agreement, contingent on the achievement of certain net sales milestones in the United States.  Subject to customary termination provisions, the License Agreement will continue as long as royalties are payable by Ironwood with respect to a Product.

In connection with the License Agreement, on the Execution Date Ironwood and AstraZeneca Pharmaceuticals LP (“AZ Pharmaceuticals”) entered into a commercial supply agreement, pursuant to which AZ Pharmaceuticals will manufacture and supply commercial supply of Zurampic to Ironwood (the “Supply Agreement”), and a transitional services agreement, pursuant to which AZ Pharmaceuticals will provide certain support services, including development, regulatory and commercial services, to Ironwood for Zurampic until such activities are transferred to Ironwood.

Ironwood, Ardea and AZ Pharmaceuticals have made customary representations and warranties and have agreed to certain customary covenants.

The foregoing summary is qualified in its entirety by reference to the License Agreement and the Supply Agreement, which Ironwood expects to file as exhibits to its Quarterly Report on Form 10-Q for the quarter ending June 30, 2016.

The full text of the press release issued by Ironwood in connection with the closing of the transaction is attached as Exhibit 99.1 to this Current Report on Form 8-K and is incorporated herein by reference.

Item 9.01    Financial Statements and Exhibits

(a)Financial Statements of Business Acquired

If financial statements are required by Item 9.01(a) of Form 8-K, Ironwood will file such financial statements by amendment within 71 calendar days after the date that this Current Report on Form 8-K is required to be filed.

(b)Pro Forma Financial Information

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If pro forma financial information is required by Item 9.01(b) of Form 8-K, Ironwood will file such pro forma financial information by amendment within 71 calendar days after the date that this Current Report on Form 8-K is required to be filed.

(d)Exhibits

Exhibit No.	Description
99.1	Ironwood Pharmaceuticals, Inc. Press Release dated June 3, 2016

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SIGNATURE

Pursuant to the requirements of the Securities Exchange Act of 1934, the registrant has duly caused this report to be signed on its behalf by the undersigned hereunto duly authorized.

IRONWOOD PHARMACEUTICALS, INC.
By:	/s/ Thomas Graney
Name:	Thomas Graney
Title:	Chief Financial Officer and Senior Vice President of Finance and Corporate Strategy

Date: June 3, 2016

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EXHIBIT INDEX

Exhibit No.	Description
99.1	Ironwood Pharmaceuticals, Inc. Press Release dated June 3, 2016

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EX-99.1

Exhibit 99.1

FOR IMMEDIATE RELEASE

Ironwood Pharmaceuticals Closes U.S. Transaction with AstraZeneca for Lesinurad

CAMBRIDGE, Mass., June 3, 2016 — Ironwood Pharmaceuticals, Inc. (NASDAQ: IRWD) announced today that it has closed the previously-announced transaction with AstraZenecafor the exclusive U.S. rights to all products containing lesinurad. Lesinurad 200mg tablets were approved as ZURAMPIC® by the U.S. Food and Drug Administration (FDA) in December 2015 for use in combination with a xanthine oxidase inhibitor (XOI) for the treatment of hyperuricemia associated with uncontrolled gout. The licensing agreement includes exclusive U.S. rights to the fixed-dose combination of lesinurad and allopurinol.  AstraZeneca plans to submit, on Ironwood’s behalf, the fixed-dose combination program for FDA regulatory review in the second half of 2016. The agreement also includes certain rights to potentially access RDEA3170 in gout indications in the U.S.

Gout is a serious, progressive and debilitating form of inflammatory arthritis. As many as two million patients in the U.S. on urate-lowering therapy have inadequately controlled hyperuricemia associated with gout, as XOI treatment alone is not sufficient to achieve their serum uric acid (sUA) treatment goals.  ZURAMPIC is not recommended for the treatment of asymptomatic hyperuricemia and should not be used as monotherapy.

About ZURAMPIC® (lesinurad) 200mg tablets

FDA-approved ZURAMPIC® (lesinurad) works selectively to complement xanthine oxidase inhibitors (XOIs) in the treatment of hyperuricemia associated with uncontrolled gout. ZURAMPIC is not recommended for the treatment of asymptomatic hyperuricemia and should not be used as monotherapy. XOIs reduce the production of uric acid; ZURAMPIC increases the excretion of uric acid. Together, the combination of ZURAMPIC and an XOI provides a dual mechanism of action that both decreases production and increases excretion of uric acid, thereby lowering serum uric acid (sUA) levels in patients who have not achieved target serum uric acid levels with XOI treatment alone. ZURAMPIC selectively inhibits the function of transporter proteins urate transporter (URAT1) and organic anion transporter 4 (OAT4), involved in uric acid reabsorption in the kidney. The safety and efficacy of ZURAMPIC was established in three Phase III clinical trials that evaluated a once-daily dose of ZURAMPIC in combination with the XOI allopurinol or febuxostat compared to XOI alone.

Important Safety Information and Limitations of Use

WARNING: RISK OF ACUTE RENAL FAILURE MORE COMMON WHEN USED
WITHOUT A XANTHINE OXIDASE INHIBITOR (XOI)

·Acute renal failure has occurred with ZURAMPIC and was more common when ZURAMPIC was given alone

·ZURAMPIC should be used in combination with an XOI

Contraindications:

·Severe renal impairment (eCLcr less than 30 mL/min), end-stage renal disease, kidney transplant recipients, or patients on dialysis

·Tumor lysis syndrome or Lesch-Nyhan syndrome

Warnings and Precautions:

·Renal events: Adverse reactions related to renal function have occurred after initiating ZURAMPIC. A higher incidence was observed at the 400-mg dose, with the highest incidence occurring with monotherapy use. Monitor renal function at initiation and during therapy with ZURAMPIC, particularly in patients with eCLcr below 60 mL/min, and evaluate for signs and symptoms of acute uric acid nephropathy. ZURAMPIC should not be initiated in patients with an eCLcr less than 45 mL/min

·Cardiovascular events: Major adverse cardiovascular events were observed with ZURAMPIC; a causal relationship has not been established

Adverse Reactions:

·Most common adverse reactions with ZURAMPIC (in combination with an XOI and more frequently than on an XOI alone) were headache, influenza, blood creatinine increased, and gastroesophageal reflux disease

Indication and Limitations of Use for ZURAMPIC

ZURAMPIC is a URAT1 inhibitor indicated in combination with an XOI for the treatment of hyperuricemia associated with gout in patients who have not achieved target serum uric acid levels with an XOI alone.

·ZURAMPIC is not recommended for the treatment of asymptomatic hyperuricemia

·ZURAMPIC should not be used as monotherapy

Please see full Prescribing Information, including Boxed Warning, at: http://www.azpicentral.com/zurampic/zurampic.pdf.

About Ironwood Pharmaceuticals

Ironwood Pharmaceuticals (NASDAQ: IRWD) is a commercial biotechnology company focused on creating medicines that make a difference for patients, building value for our fellow shareholders, and empowering our passionate team. We are advancing a pipeline of innovative medicines in areas of significant unmet need, including irritable bowel syndrome with constipation (IBS-C)/chronic idiopathic constipation (CIC), refractory gastroesophageal reflux disease, uncontrolled gout, and vascular and fibrotic diseases. We discovered, developed and

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are commercializing linaclotide, the U.S. branded prescription market leader in the IBS-C/CIC category, and we are applying our proven R&D and commercial capabilities to advance multiple internally-developed and externally-accessed product opportunities. Ironwood was founded in 1998 and is headquartered in Cambridge, Mass. For more information, please visit www.ironwoodpharma.com or www.twitter.com/ironwoodpharma; information that may be important to investors will be routinely posted in both these locations.

This press release contains forward-looking statements. Investors are cautioned not to place undue reliance on these forward-looking statements, including, but not limited to, statements about the anticipated timing of regulatory developments for the fixed-dose combination of lesinurad and allopurinol.  Applicable risks and uncertainties include, but are not limited to, decisions made by U.S. regulatory authorities, the U.S. Patent and Trademark Office and their foreign counterparts and the efficacy, safety and tolerability of the fixed-dose combination of lesinurad and allopurinol. Applicable risks also include those that are listed under the heading “Risk Factors” and elsewhere in Ironwood’s Quarterly Report on Form 10-Q for the quarter ended March 31, 2016 and in our subsequent SEC filings. These forward-looking statements (except as otherwise noted) speak only as of the date of this press release, and Ironwood undertakes no obligation to update these forward-looking statements.

Any trademarks referred to in this press release are the property of their respective owners. All rights reserved.

SOURCE: Ironwood Pharmaceuticals, Inc.

Media Relations	Investor Relations
Trista Morrison, 617-374-5095	Mary T. Conway, 617-768-2628
Director, Corporate Communications	Investor Relations
tmorrison@ironwoodpharma.com	maconway@ironwoodpharma.com

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