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):  April 11, 2014

Karyopharm Therapeutics Inc.

(Exact name of registrant as specified in its charter)

Registrant’s telephone number, including area code: (508) 975-4820

(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):

¨            Written communications pursuant to Rule 425 under the Securities Act (17 CFR 230.425)

¨            Soliciting material pursuant to Rule 14a-12 under the Exchange Act (17 CFR 240.14a-12)

¨            Pre-commencement communications pursuant to Rule 14d-2(b) under the Exchange Act (17 CFR 240.14d-2(b))

¨            Pre-commencement communications pursuant to Rule 13e-4(c) under the Exchange Act (17 CFR 240.13e-4(c))

Item 4.01.                                        Changes in Registrant’s Certifying Accountant.

On April 11, 2014, the Audit Committee of the Board of Directors of Karyopharm Therapeutics Inc. (the “Company”) selected Ernst & Young LLP (“E&Y”) as the Company’s independent registered public accounting firm for the fiscal year ending December 31, 2014, and dismissed McGladrey LLP (“McGladrey”) from service as the Company’s independent registered public accounting firm.  The Company formally engaged E&Y on April 17, 2014.

McGladrey’s reports on the Company’s financial statements as of and for the fiscal years ended December 31, 2013 and 2012 did not contain any adverse opinion or disclaimer of opinion, nor were they qualified or modified as to uncertainty, audit scope, or accounting principles.

During the fiscal years ended December 31, 2013 and 2012 and the subsequent interim period through April 11, 2014, there were (i) no “disagreements” (as that term is defined in Item 304(a)(1)(iv) of Regulation S-K and the related instructions) between the Company and McGladrey on any matter of accounting principles or practices, financial statement disclosure, or auditing scope or procedure, which disagreements, if not resolved to the satisfaction of McGladrey, would have caused McGladrey to make reference to the subject matter of the disagreement in its reports on the Company’s consolidated financial statements and (ii) no “reportable events” (as that term is defined in Item 304(a)(1)(v) of Regulation S-K).

The Company provided McGladrey with a copy of this Current Report on Form 8-K and requested that McGladrey furnish to the Company a letter addressed to the United States Securities and Exchange Commission (“SEC”) stating whether or not McGladrey agrees with the above statements and, if not, stating the respects in which it does not agree. A copy of McGladrey’s letter to the SEC, dated April 17, 2014, is attached as Exhibit 16.1 to this Current Report on Form 8-K.

During the fiscal years ended December 31, 2013 and 2012 and the subsequent interim period through April 17, 2014, neither the Company, nor anyone on its behalf, consulted E&Y regarding (i) the application of accounting principles to a specified transaction, either completed or proposed, or the type of audit opinion that might be rendered on the Company’s consolidated financial statements, and no written report or oral advice was provided to the Company by E&Y that E&Y concluded was an important factor considered by the Company in reaching a decision as to any accounting, auditing or financial reporting issue or (ii) any matter that was the subject of a “disagreement” (as that term is defined in Item 304(a)(1)(iv) of Regulation S-K and the related instructions) or a “reportable event” (as that term is defined in Item 304(a)(1)(v) of Regulation S-K).

Item 9.01.             Financial Statements and Exhibits.

(d)   Exhibits

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SIGNATURE

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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EXHIBIT INDEX

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