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):

May 31, 2018

IRONWOOD PHARMACEUTICALS, INC.

(Exact name of registrant as specified in its charter)

(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))

Indicate by check mark whether the registrant is an emerging growth company as defined in Rule 405 of the Securities Act of 1933 (§230.405 of this chapter) or Rule 12b-2 of the Securities Exchange Act of 1934 (§240.12b-2 of this chapter).

Emerging growth company o

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. o

Item 5.07  Submission of Matters to a Vote of Security Holders

On May 31, 2018, at the 2018 Annual Meeting of Stockholders (the “Annual Meeting”) of Ironwood Pharmaceuticals, Inc. (the “Company”), the stockholders of the Company voted on the following proposals:

·                  Election of three Class II directors of the Company, each to serve a three-year term;

·                  Approval, by non-binding advisory vote, of the compensation of the Company’s named executive officers, as disclosed in the Company’s proxy statement for the Annual Meeting; and

·                  Ratification of the audit committee’s selection of Ernst & Young LLP as the Company’s independent registered public accounting firm for 2018.

The final voting results for the Annual Meeting are as follows:

1.                                      The stockholders elected Lawrence S. Olanoff, Amy W. Schulman and Douglas E. Williams as Class II directors, each to serve on the board of directors of the Company for a three-year term until the annual meeting of stockholders to be held in 2021 or until his or her successor is duly elected and qualified or until his or her death, resignation or removal, based on the following votes:

2.                                      The stockholders approved, on a non-binding advisory basis, the compensation of the Company’s named executive officers, as disclosed in the Company’s proxy statement for the Annual Meeting, based on the following votes:

3.                                      The stockholders ratified the audit committee’s selection of Ernst & Young LLP as the Company’s independent registered public accounting firm for 2018, based on the following votes:

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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.

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