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): December 10, 2018

Y-MABS THERAPEUTICS, INC.

(Exact name of registrant as specified in its charter)

230 Park Avenue

Suite 3350

New York, New York 10169

(Address of principal executive offices) (Zip Code)

(646) 885-8505

(Registrant’s telephone number, include area code)

N/A

(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 8.01

On December 10, 2018, Y-mAbs Therapeutics, Inc. (the “Company”) issued a press release announcing that the U.S. Food and Drug Administration (“FDA”) has cleared the Investigational New Drug (“IND”) application for a humanized bispecific GD2 antibody. It is anticipated that a Phase 1/2 clinical trial will soon be initiated to begin screening patients with relapsed/refractory neuroblastoma, high grade osteosarcoma and other GD2(+) solid tumors, where patients have relapsed or refractory disease that is resistant to standard therapy. A copy of the press release is attached hereto as Exhibit 99.1.

The information furnished pursuant to Item 8.01 on this Form 8-K, including Exhibit 99.1 attached hereto, shall not be deemed “filed” for purposes of Section 18 of the Securities Exchange Act of 1934, as amended (the “Exchange Act”), or otherwise subject to the liabilities of that section, nor shall it be deemed incorporated by reference into any other filing under the Securities Act or the Exchange Act, except as expressly set forth by specific reference in such a filing.

Item 9.01. Financial Statements and Exhibits.

(d) Exhibits

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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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