UNITED STATES

SECURITIES AND EXCHANGE COMMISSION

WASHINGTON, DC 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): January 4, 2018

Idera Pharmaceuticals, Inc.

(Exact Name of Registrant as Specified in Charter)

Registrant’s telephone number, including area code: (617) 679-5500

(Former Name or Former Address, if Changed Since Last Report)

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))

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.

At the special meeting of stockholders of Idera Pharmaceuticals, Inc. (the “Company”) held on January 4, 2018, the Company’s stockholders voted in the following manner with respect to the following proposals:

1. The stockholders approved an amendment to the Company’s Restated Certificate of Incorporation, as amended, to effect a reverse stock split of the Company’s issued and outstanding common stock by a whole number ratio of not less than 1-for-4 and not more than 1-for-8, such ratio and the implementation and timing of such reverse stock split to be determined in the discretion of the Company’s board of directors at any time prior to the Company’s 2018 annual meeting of stockholders, and, in connection therewith, to decrease the number of authorized shares of the Company’s common stock on a basis proportional to the reverse stock split ratio.

2. The stockholders approved an amendment to the Company’s Restated Certificate of Incorporation, as amended, to set the number of authorized shares of the Company’s common stock at a number determined by calculating the product of 280,000,000 multiplied by two times (2x) the reverse stock split ratio.

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SIGNATURE

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

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