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): March 926, 2026

CARTESIAN THERAPEUTICS, INC.

(Exact name of registrant as specified in its charter)

Delaware

001-37798

26-1622110

(State or other jurisdiction
of incorporation)

(Commission
File Number)

(IRS Employer
Identification No.)

7495 New Horizon Way, Frederick, MD 21703

(Address of principal executive offices)(Zip Code)

(301) 348-8698

Registrant’s telephone number, including 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(s)	Name of each exchange on which registered
Common Stock (Par Value $0.0001)	RNAC	The Nasdaq Stock Market LLC

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 o

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. o

Item 25.02 ~~Results~~Departure of ~~Operations~~Directors ~~and~~or ~~Financial~~Certain ~~Condition~~Officers; Election of Directors; Appointment of Certain Officers; Compensatory Arrangements of Certain Officers.

On March 926, 2026, Murat Kalayoglu, M.D., Ph.D., a member of the Board of Directors (the “Board”) of Cartesian Therapeutics, Inc. (the “Company”), ~~announced~~notified ~~its~~the ~~financial~~Company ~~results~~of ~~for~~his intent to resign from the ~~year~~Board, ~~ended~~effective ~~December~~as of March 31, ~~2025~~2026, to pursue other opportunities. ~~The~~Prior ~~full~~to ~~text~~his resignation, Dr. Kalayoglu served as Chairman of the ~~press~~Board’s ~~release~~Science ~~issued~~and inTechnology Committee and as a member of the Board’s Nominating and Corporate Governance Committee. In connection with his resignation from the ~~announcement~~Board, isDr. ~~furnished~~Kalayoglu aswill ~~Exhibit~~cease 99service on such committees.1 toDr. ~~this~~Kalayoglu’s ~~Current~~resignation ~~Report~~was not the result of a disagreement with the Company on ~~Form~~any ~~8-K~~matter relating to the Company’s operations, policies or practices.

~~The information in Item 2~~Dr.02 ofKalayoglu ~~this~~served ~~Form~~on ~~8-K,~~the ~~including~~Board ~~Exhibit~~since 992023.1 ~~attached~~The ~~hereto,~~Company ~~shall~~thanks ~~not~~Dr. beKalayoglu ~~deemed “filed”~~ for ~~purposes~~his ofadvice ~~Section~~and 18leadership ~~of the Securities Exchange Act of 1934,~~ as ~~amended~~a ~~(the~~member ~~“Exchange Act”), or otherwise subject to the liabilities~~ of ~~that section, nor shall it be deemed incorporated by reference in any filing under~~ the ~~Securities~~Board ~~Act~~and ofwishes ~~1933,~~Dr. asKalayoglu ~~amended,~~well ~~or the Exchange Act, except~~ as ~~expressly~~he ~~set~~pursues ~~forth~~other ~~by specific reference in such a filing~~opportunities.

Item 9.01 Financial Statements and Exhibits.

(d) Exhibits

Exhibit No.						Exhibit Description
99.1						Press release of Cartesian Therapeutics, Inc. issued on March 9, 2026.
104						Cover Page 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.

	CARTESIAN THERAPEUTICS, INC.
Date: March 9, 2026	By:	/s/ Carsten Brunn, Ph.D.
Date: March 30, 2026	By:	/s/ Carsten Brunn, Ph.D.
		Carsten Brunn, Ph.D.
		President, Chief Executive Officer and Chairman of the Board

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