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):

February 8, 2012

IRONWOOD PHARMACEUTICALS, INC.

(Exact Name of Registrant as Specified in Charter)

Delaware	001-34620	04-3404176
(State or Other Jurisdiction	(Commission File Number)	(IRS Employer
of Incorporation)		Identification No.)

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

(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 (see General Instruction A.2. below):

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 8.01 Other Events

On February 8, 2012, Ironwood Pharmaceuticals, Inc. (the “Company”) announced that it has commenced a public offering of 5,250,000 shares of its Class A common stock, $0.001 par value per share (the “Offering”).  In connection with this Offering, the Company will grant the underwriters a 30-day option to purchase additional shares of Class A common stock equal to up to 15% of the number of shares of Class A common stock sold in the Offering.  J.P. Morgan Securities LLC and Merrill Lynch, Pierce, Fenner & Smith Incorporated are acting as joint bookrunning managers of the offering.

On February 8, 2012, the Company issued a press release announcing the Offering.  A copy of the Company’s press release is attached hereto as Exhibit 99.1 and is incorporated herein by reference.

Item 9.01 Financial Statements and Exhibits

Exhibit No.	Description
99.1	Press Release dated February 8, 2012, announcing offering of Class A common stock.

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SIGNATURES

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.
Dated: February 8, 2012	By:	/s/ Halley E. Gilbert
		Name: Halley E. Gilbert
		Title: Vice President, Legal Affairs and General Counsel

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EXHIBIT INDEX

Exhibit No.	Description
99.1	Press Release dated February 8, 2012, announcing offering of Class A common stock.

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EX-99.1

Exhibit 99.1

FOR IMMEDIATE RELEASE

Contact:

Susan Brady

Corporate Communications

617.621.8304

sbrady@ironwoodpharma.com

IRONWOOD PHARMACEUTICALS ANNOUNCES PROPOSED PUBLIC
OFFERING OF COMMON STOCK

CAMBRIDGE, Mass., February 8, 2012 — Ironwood Pharmaceuticals, Inc. (NASDAQ: IRWD) (the “Company”) announced today that it has commenced an underwritten public offering of 5,250,000 shares of its Class A common stock. All of the shares are being offered by Ironwood.  The Company will grant the underwriters a 30-day option to purchase up to an additional 787,500 shares in connection with the offering. The offering is subject to market and other conditions, and there can be no assurance as to whether or when the offering may be completed, or as to the actual size or terms of the offering. The final terms of the offering will be disclosed in a final prospectus supplement filed with the Securities and Exchange Commission (SEC).

The Company intends to use the net proceeds from this offering for general corporate purposes, including to further strengthen its balance sheet in advance of the potential market launch of linaclotide (if approved).

J.P. Morgan Securities LLC and BofA Merrill Lynch are acting as joint bookrunning managers of the offering. A preliminary prospectus supplement related to the offering has been filed with the SEC and will be available on the SEC’s website located at www.sec.gov. Copies of the preliminary prospectus supplement and the accompanying prospectus relating to this offering may be obtained from the offices of J.P. Morgan Securities LLC, c/o Broadridge Financial Solutions, 1155 Long Island Avenue, Edgewood, New York 11717 (telephone number: 866-803-9204) or from BofA Merrill Lynch, 4 World Financial Center, New York, New York 10080, Attention: Prospectus Department or by emailing dg.prospectus_requests@baml.com.

The securities described above are being offered by Ironwood pursuant to an automatically effective shelf registration statement that was previously filed with the SEC. This press release shall not constitute an offer to sell, or the solicitation of an offer to buy, any of the securities, nor shall there be any sale of these securities, in any state or jurisdiction in which such offer, solicitation or sale would be unlawful prior to registration or qualification under the securities laws of any such state or jurisdiction.

About Ironwood Pharmaceuticals

Ironwood Pharmaceuticals (NASDAQ: IRWD) is an entrepreneurial pharmaceutical company dedicated to the art and science of great drugmaking. Linaclotide, Ironwood’s GC-C agonist, is an investigational drug for the treatment of irritable bowel syndrome with constipation (IBS-C) and chronic constipation (CC). The efficacy portion of linaclotide’s development program has been completed and supports the recently submitted NDA for both indications, as well as the MAA submission in Europe for the IBS-C indication. Ironwood also has a growing pipeline of additional drug candidates in earlier stages of development. Ironwood is located in Cambridge, Mass.

Caution Regarding Forward-Looking Statements

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 relating to Ironwood’s expectations regarding the completion, timing and size of the proposed offering and use of proceeds. Each forward-looking statement is subject to risks and uncertainties that could cause actual results to differ materially from those expressed or implied in such statement. Applicable risks and uncertainties include, but are not limited to, those associated with market conditions and the satisfaction of customary closing conditions related to the proposed offering. Applicable risks also include those that are included in Ironwood’s Quarterly Report on Form 10-Q for the three months ended September 30, 2011, in addition to the risk factors that are included from time to time in Ironwood’s Annual Reports on Form 10-K, Quarterly Reports on Form 10-Q, and any subsequent SEC filings, including the prospectus supplement related to the proposed offering to be filed with the SEC. Ironwood undertakes no obligation to update these forward-looking statements to reflect events or circumstances occurring after this press release. These forward-looking statements speak only as of the date of this press release. All forward-looking statements are qualified in their entirety by this cautionary statement.

SOURCE: Ironwood Pharmaceuticals, Inc.

Ironwood Pharmaceuticals, Inc.
Susan Brady, Corporate Communications

617.621.8304
sbrady@ironwoodpharma.com

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