Adage reports 9.99% stake in Pasithea Therapeutics (NASDAQ: KTTA)

Rhea-AI Filing Summary

Adage Capital Management, L.P. and related reporting persons report a 2,329,749-share beneficial stake, or 9.99% of Pasithea Therapeutics Corp. common stock. This total includes 229,749 shares issuable upon exercise of warrants held by Adage Capital Partners, L.P.

The stake, tied to an event date of December 31, 2025, is reported as being held in the ordinary course of business and not for the purpose of changing or influencing control of Pasithea. Voting and dispositive power over all reported shares is shared among the reporting persons.

SECURITIES AND EXCHANGE COMMISSION
Washington, D.C. 20549

SCHEDULE 13G

UNDER THE SECURITIES EXCHANGE ACT OF 1934

Pasithea Therapeutics Corp.

(Name of Issuer)

Common Stock, par value $0.0001 per share

(Title of Class of Securities)

70261F202

(CUSIP Number)

12/31/2025

(Date of Event Which Requires Filing of this Statement)

Check the appropriate box to designate the rule pursuant to which this Schedule is filed:

Rule 13d-1(b)

Rule 13d-1(c)

Rule 13d-1(d)

SCHEDULE 13G

CUSIP No. 70261F202

1

Names of Reporting Persons

Adage Capital Management, L.P.

2

Check the appropriate box if a member of a Group (see instructions)

(a)
(b)

3

Sec Use Only

4

Citizenship or Place of Organization

DELAWARE

Number of Shares Beneficially Owned by Each Reporting Person With:

5	Sole Voting Power 0.00
6	Shared Voting Power 2,329,749.00
7	Sole Dispositive Power 0.00
8	Shared Dispositive Power 2,329,749.00

9

Aggregate Amount Beneficially Owned by Each Reporting Person

2,329,749.00

10

Check box if the aggregate amount in row (9) excludes certain shares (See Instructions)

11

Percent of class represented by amount in row (9)

9.99 %

12

Type of Reporting Person (See Instructions)

IA, PN

Comment for Type of Reporting Person: Includes 229,749 shares of Common Stock (as defined in Item 2(a)) issuable upon exercise of warrants.

SCHEDULE 13G

CUSIP No. 70261F202

1

Names of Reporting Persons

Robert Atchinson

2

Check the appropriate box if a member of a Group (see instructions)

(a)
(b)

3

Sec Use Only

4

Citizenship or Place of Organization

UNITED STATES

Number of Shares Beneficially Owned by Each Reporting Person With:

5	Sole Voting Power 0.00
6	Shared Voting Power 2,329,749.00
7	Sole Dispositive Power 0.00
8	Shared Dispositive Power 2,329,749.00

9

Aggregate Amount Beneficially Owned by Each Reporting Person

2,329,749.00

10

Check box if the aggregate amount in row (9) excludes certain shares (See Instructions)

11

Percent of class represented by amount in row (9)

9.99 %

12

Type of Reporting Person (See Instructions)

HC, IN

Comment for Type of Reporting Person: Includes 229,749 shares of Common Stock issuable upon exercise of warrants.

SCHEDULE 13G

CUSIP No. 70261F202

1

Names of Reporting Persons

Phillip Gross

2

Check the appropriate box if a member of a Group (see instructions)

(a)
(b)

3

Sec Use Only

4

Citizenship or Place of Organization

UNITED STATES

Number of Shares Beneficially Owned by Each Reporting Person With:

5	Sole Voting Power 0.00
6	Shared Voting Power 2,329,749.00
7	Sole Dispositive Power 0.00
8	Shared Dispositive Power 2,329,749.00

9

Aggregate Amount Beneficially Owned by Each Reporting Person

2,329,749.00

10

Check box if the aggregate amount in row (9) excludes certain shares (See Instructions)

11

Percent of class represented by amount in row (9)

9.99 %

12

Type of Reporting Person (See Instructions)

HC, IN

Comment for Type of Reporting Person: Includes 229,749 shares of Common Stock issuable upon exercise of warrants.

SCHEDULE 13G

Item 1.
(a)	Name of issuer: Pasithea Therapeutics Corp.
(b)	Address of issuer's principal executive offices: 1111 Lincoln Road, Suite 500, Miami Beach, FL 33139
Item 2.
(a)	Name of person filing: This statement is filed by: (i) Adage Capital Management, L.P., a Delaware limited partnership ("ACM"), as the investment manager of Adage Capital Partners, L.P., a Delaware limited partnership ("ACP"), with respect to the shares of Common Stock, par value $0.0001 per share ("Common Stock") of Pasithea Therapeutics Corp., a Delaware corporation (the "Company") and shares of Common Stock issuable upon exercise of warrants directly held by ACP; (ii) Robert Atchinson ("Mr. Atchinson"), as (1) managing member of Adage Capital Advisors, L.L.C., a limited liability company organized under the laws of the State of Delaware ("ACA"), managing member of Adage Capital Partners GP, L.L.C., a limited liability company organized under the laws of the State of Delaware ("ACPGP"), general partner of ACP and (2) managing member of Adage Capital Partners LLC, a Delaware limited liability company ("ACPLLC"), general partner of ACM, with respect to the shares of Common Stock and shares of Common Stock issuable upon exercise of warrants directly held by ACP; and (iii) Phillip Gross ("Mr. Gross"), as (1) managing member of ACA, managing member of ACPGP and (2) managing member of ACPLLC, general partner of ACM, with respect to the shares of Common Stock and shares of Common Stock issuable upon exercise of warrants directly held by ACP. The foregoing persons are hereinafter sometimes collectively referred to as the "Reporting Persons." Any disclosures herein with respect to persons other than the Reporting Persons are made on information and belief after making inquiry to the appropriate party. The filing of this statement should not be construed in and of itself as an admission by any Reporting Person as to beneficial ownership of the securities reported herein.
(b)	Address or principal business office or, if none, residence: The address of the business office of each of the Reporting Persons is 200 Clarendon Street, 52nd Floor, Boston, Massachusetts 02116.
(c)	Citizenship: ACM is a limited partnership organized under the laws of the State of Delaware. Messrs. Gross and Atchinson are citizens of the United States.
(d)	Title of class of securities: Common Stock, par value $0.0001 per share
(e)	CUSIP No.: 70261F202
Item 3.	If this statement is filed pursuant to §§ 240.13d-1(b) or 240.13d-2(b) or (c), check whether the person filing is a:
(a)	Broker or dealer registered under section 15 of the Act (15 U.S.C. 78o);
(b)	Bank as defined in section 3(a)(6) of the Act (15 U.S.C. 78c);
(c)	Insurance company as defined in section 3(a)(19) of the Act (15 U.S.C. 78c);
(d)	Investment company registered under section 8 of the Investment Company Act of 1940 (15 U.S.C. 80a-8);
(e)	An investment adviser in accordance with § 240.13d-1(b)(1)(ii)(E);
(f)	An employee benefit plan or endowment fund in accordance with § 240.13d-1(b)(1)(ii)(F);
(g)	A parent holding company or control person in accordance with § 240.13d-1(b)(1)(ii)(G);
(h)	A savings associations as defined in Section 3(b) of the Federal Deposit Insurance Act (12 U.S.C. 1813);
(i)	A church plan that is excluded from the definition of an investment company under section 3(c)(14) of the Investment Company Act of 1940 (15 U.S.C. 80a-3);
(j)	A non-U.S. institution in accordance with § 240.13d-1(b)(1)(ii)(J). If filing as a non-U.S. institution in accordance with § 240.13d-1(b)(1)(ii)(J), please specify the type of institution:
(k)	Group, in accordance with Rule 240.13d-1(b)(1)(ii)(K).
Item 4.	Ownership
(a)	Amount beneficially owned: The information required by Item 4(a) is set forth in Row 9 of the cover page for each of the Reporting Persons and is incorporated herein by reference. The percentage set forth in this Schedule 13G is calculated based upon an aggregate of 23,091,062 shares of Common Stock outstanding as of December 22, 2025, as reported in the Company's Definitive Proxy Statement on Schedule 14A filed with the Securities and Exchange Commission on December 29, 2025, and assumes the exercise of warrants held by the ACP.
(b)	Percent of class: 9.99%
(c)	Number of shares as to which the person has:
	(i) Sole power to vote or to direct the vote: The information required by Item 4(c)(i) is set forth in Row 5 of the cover page for each of the Reporting Persons and is incorporated herein by reference.
	(ii) Shared power to vote or to direct the vote: The information required by Item 4(c)(ii) is set forth in Row 6 of the cover page for each of the Reporting Persons and is incorporated herein by reference.
	(iii) Sole power to dispose or to direct the disposition of: The information required by Item 4(c)(iii) is set forth in Row 7 of the cover page for each of the Reporting Persons and is incorporated herein by reference.
	(iv) Shared power to dispose or to direct the disposition of: The information required by Item 4(c)(iv) is set forth in Row 8 of the cover page for each of the Reporting Persons and is incorporated herein by reference.
Item 5.	Ownership of 5 Percent or Less of a Class.
	Not Applicable
Item 6.	Ownership of more than 5 Percent on Behalf of Another Person.
	If any other person is known to have the right to receive or the power to direct the receipt of dividends from, or the proceeds from the sale of, such securities, a statement to that effect should be included in response to this item and, if such interest relates to more than 5 percent of the class, such person should be identified. A listing of the shareholders of an investment company registered under the Investment Company Act of 1940 or the beneficiaries of employee benefit plan, pension fund or endowment fund is not required. See Item 2(a).
Item 7.	Identification and Classification of the Subsidiary Which Acquired the Security Being Reported on by the Parent Holding Company or Control Person.
	Not Applicable
Item 8.	Identification and Classification of Members of the Group.
	Not Applicable
Item 9.	Notice of Dissolution of Group.
	Not Applicable

Item 10.

Certifications:

By signing below I certify that, to the best of my knowledge and belief, the securities referred to above were acquired and are held in the ordinary course of business and were not acquired and are not held for the purpose of or with the effect of changing or influencing the control of the issuer of the securities and were not acquired and are not held in connection with or as a participant in any transaction having that purpose or effect, other than activities solely in connection with a nomination under ?? 240.14a-11.

SIGNATURE

After reasonable inquiry and to the best of my knowledge and belief, I certify that the information set forth in this statement is true, complete and correct.

Adage Capital Management, L.P.

Signature:	/s/ Robert Atchinson
Name/Title:	By: Adage Capital Partners LLC, its General Partner, By: Robert Atchinson, its Managing Member
Date:	02/12/2026

Robert Atchinson

Signature:	/s/ Robert Atchinson
Name/Title:	Robert Atchinson, individually
Date:	02/12/2026

Phillip Gross

Signature:	/s/ Phillip Gross
Name/Title:	Phillip Gross, individually
Date:	02/12/2026

Exhibit Information

Exhibit 99.1: Joint Filing Agreement

FAQ

What stake in Pasithea Therapeutics (KTTA) does Adage report on this Schedule 13G?

Adage and related reporting persons report beneficial ownership of 2,329,749 Pasithea Therapeutics common shares, representing 9.99% of the class. This figure includes both currently outstanding shares and 229,749 shares issuable upon exercise of warrants held by Adage Capital Partners.

How is the 9.99% ownership in Pasithea Therapeutics (KTTA) calculated?

The 9.99% figure is based on 23,091,062 Pasithea common shares outstanding as of December 22, 2025, as referenced from a company proxy statement. The percentage also assumes exercise of the warrants held by Adage Capital Partners, which add to the reported beneficial ownership.

Does Adage’s 13G filing for Pasithea (KTTA) indicate an attempt to influence control?

The reporting persons certify the securities were acquired and are held in the ordinary course of business, not to change or influence control of Pasithea. They also state the holdings are not part of any transaction intended to affect control, aside from activities tied to a nomination rule reference.

Who are the reporting persons in the Pasithea Therapeutics (KTTA) Schedule 13G?

The filing lists Adage Capital Management, L.P., along with individuals Robert Atchinson and Phillip Gross, as reporting persons. Adage Capital Management acts as investment manager to Adage Capital Partners, L.P., which directly holds the Pasithea common shares and related warrants described in the filing.

What role do warrants play in Adage’s Pasithea (KTTA) ownership?

The reported ownership includes 229,749 Pasithea common shares issuable upon exercise of warrants held by Adage Capital Partners. These warrant shares are counted toward the 2,329,749 total beneficially owned, which in turn is used to calculate the reported 9.99% ownership of the common stock class.

What voting and dispositive powers are reported over Pasithea (KTTA) shares?

The reporting persons disclose zero sole voting and dispositive power, and shared voting and dispositive power over 2,329,749 shares. This means decisions to vote or dispose of the reported Pasithea shares are shared among the reporting persons rather than controlled individually by any one of them.