15-12G 1 tm2529647d1_1512g.htm FORM 15-12G

UNITED STATES
SECURITIES AND EXCHANGE COMMISSION

Washington, D.C. 20549

FORM 15

CERTIFICATION AND NOTICE OF TERMINATION OF REGISTRATION
UNDER SECTION 12(g) OF THE SECURITIES EXCHANGE ACT OF 1934
OR SUSPENSION OF DUTY TO FILE REPORTS UNDER SECTIONS 13 AND 15(d)
OF THE SECURITIES EXCHANGE ACT OF 1934

Commission File Number: 001-40384

Tourmaline Bio, Inc.

(Exact name of registrant as specified in its charter)

27 West 24th Street, Suite 702

New York, NY 10010

(646) 481-9832
(Address, including zip code, and telephone number, including area code, of registrant’s principal executive offices)

Common Stock, par value $0.0001 per share
(Title of each class of securities covered by this Form)

None
(Titles of all other classes of securities for which a duty to file reports under section 13(a) or 15(d) remains)

Please place an X in the box(es) to designate the appropriate rule provision(s) relied upon to terminate or suspend the duty to file reports:

Rule 12g-4(a)(1)	x
Rule 12g-4(a)(2)	¨
Rule 12h-3(b)(1)(i)	x
Rule 12h-3(b)(1)(ii)	¨
Rule 15d-6	¨
Rule 15d-22(b)	¨

Approximate number of holders of record as of the certification or notice date: One (1)

Pursuant to the requirements of the Securities Exchange Act of 1934, Regulus Therapeutics Inc. has caused this certification/notice to be signed on its behalf by the undersigned duly authorized person.

	TOURMALINE BIO, INC.

Date: November 7, 2025	By:	/s/ Jaime Huertas
		Name:	Jaime Huertas
		Title:	Secretary

SEC Form 15-12G filed by Tourmaline Bio Inc.