PRQR ProQR Therapeutics NV

UNITED STATES

SECURITIES AND EXCHANGE COMMISSION

Washington, D.C. 20549

FORM 6-K

Report of Foreign Private Issuer

Pursuant to Rule 13a-16 or 15d-16 of

the Securities Exchange Act of 1934

May 8, 2019

PROQR THERAPEUTICS N.V.

Zernikedreef 9

2333 CK Leiden

The Netherlands

Tel: +31 88 166 7000

(Address, Including ZIP Code, and Telephone Number,
Including Area Code, of Registrant’s Principal Executive Offices)

Indicate by check mark whether the registrant files or will file annual reports under cover of Form 20-F or Form 40-F.

Form 20-F  x   Form 40-F  o

Indicate by check mark if the registrant is submitting the Form 6-K in paper as permitted by Regulation S-T Rule 101(b)(1):  o

Indicate by check mark if the registrant is submitting the Form 6-K in paper as permitted by Regulation S-T Rule 101(b)(7):  o

Attached as Exhibit 99.1 to this Report on Form 6-K is a press release of ProQR Therapeutics N.V. (the “Company”) dated May 8, 2019, announcing the Company’s results for the three month period ended March 31, 2019, and furnished as Exhibit 99.2 to this Report on Form 6-K are the unaudited financial statements of the Company for the three month period ended March 31, 2019.

The Company hereby incorporates by reference the information contained herein into the Company’s registration statement on Form F-3 (File No. 333-228251).

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