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): May 28, 2025

Y-MABS THERAPEUTICS, INC.

(Exact name of registrant as specified in its charter)

Delaware

001-38650

47-4619612

(State or other jurisdiction of

incorporation or organization)

(Commission

File Number)

(I.R.S. Employer

Identification No.)

202 Carnegie Center

Suite 301

Princeton, New Jersey 08540

(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:

¨	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))

Securities registered pursuant to Section 12(b) of the Act:

Title of each class:		Trading Symbol		Name of each exchange on which registered
Common Stock, $0.0001 par value		YMAB		NASDAQ Global Select Market

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 ¨

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. ¨

Item 7.01 Regulation FD Disclosure.

On May 28, 2025, Y-mAbs Therapeutics, Inc. (the “Company”) is holding a virtual research and development update (the “R&D Update”) regarding progress across its Radiopharmaceutical business unit. A copy of the slide presentation is furnished as Exhibit 99.1 hereto and incorporated herein by reference.

The information in this Item 7.01 and Exhibit 99.1 of this Current Report on Form 8-K is being furnished to the Securities and Exchange Commission and 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 liability under that section, nor shall it be deemed incorporated by reference in any filing under the Exchange Act or the Securities Act of 1933, as amended, except as expressly set forth by specific reference in such a filing.

Item 8.01 OTHER EVENTS.

In connection with the R&D Update, on May 28, 2025, the Company issued a press release discussing complete Part A data from its GD2-Self-Assembly DisAssembly (“SADA”) Phase 1 Clinical Trial (Trial 1001) as well as its strategy for development of its SADA program. The full text of the Company’s press release is filed as Exhibit 99.2 to this Current Report on Form 8-K and is incorporated herein by reference.

ITEM 9.01. FINANCIAL STATEMENTS AND EXHIBITS.

(d) Exhibits

Exhibit No.		Description
99.1		Presentation, dated May 28, 2025.
99.2		Press Release, dated May 28, 2025, issued by Y-mAbs Therapeutics, Inc.
104		Interactive Data File (embedded within the Inline XBRL document).

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.

	Y-MABS THERAPEUTICS, INC.

Date: May 28, 2025	By:	/s/ Michael Rossi
		Michael Rossi
		President and Chief Executive Officer

Y-mAbs Therapeutics, Inc. 8-K