CONSENT OF INDEPENDENT REGISTERED PUBLIC ACCOUNTING FIRM
We consent to the use in this Amendment No. 1 to Registration Statement No. 333-213917 on Form S-1 of our report dated August 17, 2016 relating to the consolidated financial statements of Ra Pharmaceuticals, Inc. (which report expresses an unqualified opinion and includes an explanatory paragraph regarding substantial doubt about the Company's ability to continue as a going concern) appearing in the Prospectus, which is part of this Registration Statement. We also consent to the reference to us under the heading "Experts" in such Prospectus.
/s/ Deloitte & Touche LLP
Boston, Massachusetts
October 13, 2016
