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 28, 2018

RA PHARMACEUTICALS, INC.

(Exact name of Registrant as Specified in Its Charter)

(617) 401-4060

(Registrant’s telephone number, include area code)

Not Applicable

(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

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 x

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. x

Item 5.07. Submission of Matters to a Vote of Security Holders.

On June 28, 2018, Ra Pharmaceuticals, Inc. (the “Company”) held its Annual Meeting of Stockholders.  A total of 26,263,521 shares of common stock were present in person or represented by proxy at the meeting, representing approximately 81.3 percent of the Company’s outstanding common stock as of the April 30, 2018 record date. The following are the voting results for the proposals considered and voted upon at the meeting, all of which were described in the Company’s definitive proxy statement filed with the Securities and Exchange Commission on April 27, 2018 and amended and restated on May 7, 2018.

Item 1 — Election of two Class II directors to serve until the 2021 Annual Meeting of Stockholders, and until their respective successors have been duly elected and qualified.

Item 2 — Ratification of the appointment of Deloitte & Touche LLP as the Company’s independent registered public accounting firm for the year ending December 31, 2018.

Based on the foregoing votes, Robert Heft, Ph.D. and Rajeev Shah were elected as Class II directors and Item 2 was approved.

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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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