SESN / Sesen Bio Inc. - Pengajuan SECLaporan Tahunan, Pernyataan Proksi

Sesen Bio Inc.
US ˙ NASDAQ ˙ US8177631053
HINDI NA ACTIVE ANG SIMBONG ITO

Mga Batayang Estadistika
LEI 549300DGKHONOZQIY116
CIK 1485003
SEC Filings
All companies that sell securities in the United States must register with the Securities and Exchange Commission (SEC) and file reports on a regular basis. These reports include company annual reports (10K, 10Q), news updates (8K), investor presentations (found in 8Ks), insider trades (form 4), ownership reports (13D, and 13G), and reports related to the specific securities sold, such as registration statements and prospectus. This page shows recent SEC filings related to Sesen Bio Inc.
SEC Filings (Chronological Order)
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August 29, 2025 EX-10.46

CARISMA THERAPEUTICS INC.

EXHIBIT 10.46 CARISMA THERAPEUTICS INC. August 29, 2025 Steven Kelly [**] Re: Retention and Transaction Bonus Agreement Dear Steven: As we discussed, Carisma Therapeutics Inc. (the “Company”) recognizes and appreciates the contributions you have made to the Company during your employment and in support of the anticipated merger pursuant to that certain Agreement and Plan of Merger, dated June 22,

August 29, 2025 S-4/A

As filed with the Securities and Exchange Commission on August 29, 2025

Table of Contents As filed with the Securities and Exchange Commission on August 29, 2025 Registration No.

August 29, 2025 EX-10.41

TRANSITION SERVICES AGREEMENT Ocugen, Inc. OrthoCellix, Inc. dated as of [October] __, 2025 TRANSITION SERVICES AGREEMENT

Exhibit 10.41 TRANSITION SERVICES AGREEMENT between Ocugen, Inc. and OrthoCellix, Inc. dated as of [October] , 2025 TRANSITION SERVICES AGREEMENT This Transition Services Agreement, dated as of [October] , 2025 (this "Agreement"), is entered into between Ocugen, Inc., a Delaware corporation ("Ocugen"), and OrthoCellix, Inc., a Delaware corporation ("OrthoCellix"). Recitals WHEREAS, OrthoCellix and

August 29, 2025 EX-10.3

COLLABORATION AND LICENSE AGREEMENT by and among CARISMA THERAPEUTICS INC. MODERNATX, INC. Dated as of January 7, 2022

EXHIBIT 10.3 Certain identified information has been excluded from the exhibit because it is both (i) not material and (ii) is the type of information that the registrant treats as private or confidential. Double asterisks denote omissions. COLLABORATION AND LICENSE AGREEMENT by and among CARISMA THERAPEUTICS INC. and MODERNATX, INC. Dated as of January 7, 2022 ARTICLE I. DEFINITIONS 1 ARTICLE II.

August 29, 2025 EX-FILING FEES

Security Type

Calculation of Filing Fee Tables S-4 Carisma Therapeutics Inc. Table 1: Newly Registered and Carry Forward Securities ☐Not Applicable Security Type Security Class Title Fee Calculation or Carry Forward Rule Amount Registered Proposed Maximum Offering Price Per Unit Maximum Aggregate Offering Price Fee Rate Amount of Registration Fee Carry Forward Form Type Carry Forward File Number Carry Forward I

August 29, 2025 EX-10.42

MANUFACTURING AND SUPPLY AGREEMENT

Exhibit 10.42 MANUFACTURING AND SUPPLY AGREEMENT This Manufacturing and Supply Agreement (“Agreement”) dated October , 2025 (the “Effective Date”), is made by and between Ocugen, Inc., a Delaware corporation with an address at 11 Great Valley Parkway, Malvern, PA 19355, USA (“Ocugen”), and OrthoCellix, Inc., a Delaware corporation with an address at (“OrthoCellix”). Ocugen and OrthoCellix are some

August 29, 2025 EX-10.1

EMPLOYMENT AGREEMENT

Exhibit 10.1 EMPLOYMENT AGREEMENT THIS AMENDED AND RESTATED EMPLOYMENT AGREEMENT (the “Agreement”), is made as of August 29, 2025 and amends and restates the Employment Agreement (the “Prior Agreement”) dated March 7, 2023, by and between Carisma Therapeutics Inc., a Delaware corporation (the “Company”), and Steven Kelly (the “Executive”) (together, the “Parties”). RECITALS WHEREAS, the Executive

August 29, 2025 EX-10.2

CARISMA THERAPEUTICS INC.

Exhibit 10.2 CARISMA THERAPEUTICS INC. August 29, 2025 Steven Kelly [**] Re: Retention and Transaction Bonus Agreement Dear Steven: As we discussed, Carisma Therapeutics Inc. (the “Company”) recognizes and appreciates the contributions you have made to the Company during your employment and in support of the anticipated merger pursuant to that certain Agreement and Plan of Merger, dated June 22, 2

August 29, 2025 425

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): August 29, 2025 Carisma Therapeut

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): August 29, 2025 Carisma Therapeutics Inc. (Exact Name of Registrant as Specified in its Charter) Delaware 001-36296 26-2025616 (State or other jurisdiction of incorporation) (Commissi

August 29, 2025 8-K

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): August 29, 2025 Carisma Therapeut

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): August 29, 2025 Carisma Therapeutics Inc. (Exact Name of Registrant as Specified in its Charter) Delaware 001-36296 26-2025616 (State or other jurisdiction of incorporation) (Commissi

August 29, 2025 EX-10.47

EMPLOYMENT AGREEMENT

EXHIBIT 10.47 EMPLOYMENT AGREEMENT THIS AMENDED AND RESTATED EMPLOYMENT AGREEMENT (the “Agreement”), is made as of August 29, 2025 and amends and restates the Employment Agreement (the “Prior Agreement”) dated March 7, 2023, by and between Carisma Therapeutics Inc., a Delaware corporation (the “Company”), and Steven Kelly (the “Executive”) (together, the “Parties”). RECITALS WHEREAS, the Executive

August 29, 2025 EX-10.1

EMPLOYMENT AGREEMENT

Exhibit 10.1 EMPLOYMENT AGREEMENT THIS AMENDED AND RESTATED EMPLOYMENT AGREEMENT (the “Agreement”), is made as of August 29, 2025 and amends and restates the Employment Agreement (the “Prior Agreement”) dated March 7, 2023, by and between Carisma Therapeutics Inc., a Delaware corporation (the “Company”), and Steven Kelly (the “Executive”) (together, the “Parties”). RECITALS WHEREAS, the Executive

August 29, 2025 EX-10.2

CARISMA THERAPEUTICS INC.

Exhibit 10.2 CARISMA THERAPEUTICS INC. August 29, 2025 Steven Kelly [**] Re: Retention and Transaction Bonus Agreement Dear Steven: As we discussed, Carisma Therapeutics Inc. (the “Company”) recognizes and appreciates the contributions you have made to the Company during your employment and in support of the anticipated merger pursuant to that certain Agreement and Plan of Merger, dated June 22, 2

August 29, 2025 EX-99.4

Consent to be Named as a Director

Exhibit 99.4 Consent to be Named as a Director Carisma Therapeutics Inc. is filing a Registration Statement on Form S-4 (the “Registration Statement”) with the Securities and Exchange Commission under the Securities Act of 1933, as amended (the “Securities Act”). In connection therewith, I hereby consent, pursuant to Rule 438 of the Securities Act, to being named in the Registration Statement and

August 29, 2025 EX-99.5

Consent to be Named as a Director

Exhibit 99.5 Consent to be Named as a Director Carisma Therapeutics Inc. is filing a Registration Statement on Form S-4 (the “Registration Statement”) with the Securities and Exchange Commission under the Securities Act of 1933, as amended (the “Securities Act”). In connection therewith, I hereby consent, pursuant to Rule 438 of the Securities Act, to being named in the Registration Statement and

August 8, 2025 425

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): August 5, 2025 Carisma Therapeuti

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): August 5, 2025 Carisma Therapeutics Inc. (Exact Name of Registrant as Specified in its Charter) Delaware 001-36296 26-2025616 (State or other jurisdiction of incorporation) (Commissio

August 8, 2025 8-K

Current Report

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): August 5, 2025 Carisma Therapeutics Inc. (Exact Name of Registrant as Specified in its Charter) Delaware 001-36296 26-2025616 (State or other jurisdiction of incorporation) (Commissio

August 7, 2025 10-Q

UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 FORM 10-Q

Table of Contents UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 FORM 10-Q x QUARTERLY REPORT PURSUANT TO SECTION 13 OR 15(d) OF THE SECURITIES EXCHANGE ACT OF 1934 For the quarterly period ended June 30, 2025 OR o TRANSITION REPORT PURSUANT TO SECTION 13 OR 15(d) OF THE SECURITIES EXCHANGE ACT OF 1934 For the transition period from to Commission File Number: 001-36296 Car

July 31, 2025 DEFA14A

UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 SCHEDULE 14A Proxy Statement Pursuant to Section 14(a) of the Securities Exchange Act of 1934 (Amendment No.     )

UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 SCHEDULE 14A Proxy Statement Pursuant to Section 14(a) of the Securities Exchange Act of 1934 (Amendment No.     ) Filed by the Registrant x Filed by a Party other than the Registrant ¨ Check the appropriate box: ¨ Preliminary Proxy Statement ¨ Confidential, for Use of the Commission Only (as permitted by Rule 14a-6(e)(2)) ¨ D

July 21, 2025 EX-10.44

Exclusive Channel Collaboration Agreement dated as of September 30, 2014 between Ocugen, Inc. and Intrexon Corporation

Exhibit 10.44 Certain identified information has been excluded from this exhibit because it is both not material and is the type that the registrant treats as private or confidential. Information that was omitted has been noted in this document with a placeholder identified by the mark “[***]”. EXCLUSIVE CHANNEL COLLABORATION AGREEMENT THIS EXCLUSIVE CHANNEL COLLABORATION AGREEMENT (the “Agreement

July 21, 2025 EX-10.38

Agreement, dated June 22, 2012 between Ocugen, Inc. and Purpose Co., Ltd. f/k/a Takagi Sangyo Co. Ltd. and f/k/a Takagi Industrial Co., Ltd.

Exhibit 10.38 Certain identified information has been excluded from this exhibit because it is both not material and is the type that the registrant treats as private or confidential. Information that was omitted has been noted in this document with a placeholder identified by the mark “[***]”. AGREEMENT Agreement made and entered into as of the 22nd day of June, 2012, by and between Purpose Co.,

July 21, 2025 EX-3.4

By-Laws of OrthoCellix, Inc., as currently in effect.

Exhibit 3.4 ORTHOCELLIX, INC. BYLAWS Adopted: June 19, 2025 ARTICLE I STOCKHOLDERS Section 1.Annual Meeting. An annual meeting of the stockholders, for the election of directors to succeed those whose terms expire and for the transaction of such other business as may properly come before the meeting, shall be held at such place, if any, on such date, and at such time as the Board of Directors (or

July 21, 2025 EX-10.45

Mutual Termination and Release Agreement dated December 21, 2018, between Histogenics Corporation and Intrexon Corporation.

Exhibit 10.45 MUTUAL TERMINATION AND RELEASE AGREEMENT THIS MUTUAL TERMINATION AND RELEASE AGREEMENT (the “Agreement”) is made as of December 21, 2018 (the “Effective Date”) by and between Histogenics Corporation, a Delaware corporation (“Histogenics”), and Intrexon Corporation, a Virginia corporation (“Intrexon”). Histogenics and Intrexon are from time to time referred to herein individually as a

July 21, 2025 EX-99.3

Consent of David Anderson to serve as a director of Carisma Therapeutics Inc., to be renamed OrthoCellix, Inc.

Exhibit 99.3 Consent to be Named as a Director Carisma Therapeutics Inc. is filing a Registration Statement on Form S-4 (the “Registration Statement”) with the Securities and Exchange Commission under the Securities Act of 1933, as amended (the “Securities Act”). In connection therewith, I hereby consent, pursuant to Rule 438 of the Securities Act, to being named in the Registration Statement and

July 21, 2025 EX-3.3

Certificate of Incorporation of OrthoCellix, Inc., as currently in effect.

Exhibit 3.3 CERTIFICATE OF INCORPORATION OF ORTHOCELLIX, INC. Article I The name of this corporation is OrthoCellix, Inc. (the “Corporation”). Article II The address of the Corporation’s registered office in the State of Delaware is 1209 Orange Street, in the City of Wilmington, County of New Castle, 19801, and its registered agent at such address is The Corporation Trust Company. Article III The

July 21, 2025 EX-FILING FEES

Filing Fee Table

Exhibit 107 Calculation of Filing Fee Tables Form S-4 (Form Type) CARISMA THERAPEUTICS INC.

July 21, 2025 EX-10.37

Eighth Amendment to License Agreement, dated June 29, 2012 among Ocugen, Inc. and Angiotech Pharmaceuticals (US), Inc. and Angiodevice International GmbH.

Exhibit 10.37 Certain identified information has been excluded from this exhibit because it is both not material and is the type that the registrant treats as private or confidential. Information that was omitted has been noted in this document with a placeholder identified by the mark “[***]”. EIGHTH AMENDMENT TO LICENSE AGREEMENT THIS EIGHTH AMENDMENT TO LICENSE AGREEMENT (this “Eighth Amendment

July 21, 2025 EX-10.29

License Agreement, dated May 12, 2005, among Ocugen, Inc. and Angiotech Pharmaceuticals (US), Inc. and Angiodevice International GmbH.

Exhibit 10.29 Certain identified information has been excluded from this exhibit because it is both not material and is the type that the registrant treats as private or confidential. Information that was omitted has been noted in this document with a placeholder identified by the mark “[***]”. LICENSE AGREEMENT This License Agreement, effective as of May 12, 2005 (the “Effective Date”), is by and

July 21, 2025 EX-99.2

Consent of Michael Shine to serve as a director of Carisma Therapeutics Inc., to be renamed OrthoCellix, Inc.

Exhibit 99.2 Consent to be Named as a Director Carisma Therapeutics Inc. is filing a Registration Statement on Form S-4 (the “Registration Statement”) with the Securities and Exchange Commission under the Securities Act of 1933, as amended (the “Securities Act”). In connection therewith, I hereby consent, pursuant to Rule 438 of the Securities Act, to being named in the Registration Statement and

July 21, 2025 EX-10.31

Second Amendment to License Agreement, dated January 1, 2008 among Ocugen, Inc. and Angiotech Pharmaceuticals (US), Inc. and Angiodevice International GmbH.

Exhibit 10.31 Certain identified information has been excluded from this exhibit because it is both not material and is the type that the registrant treats as private or confidential. Information that was omitted has been noted in this document with a placeholder identified by the mark “[***]”. SECOND AMENDMENT TO LICENSE AGREEMENT THIS SECOND AMENDMENT TO LICENSE AGREEMENT (this “Second Amendment

July 21, 2025 EX-10.34

Fifth Amendment to License Agreement, dated August 6, 2010 among Ocugen, Inc. and Angiotech Pharmaceuticals (US), Inc. and Angiodevice International GmbH.

Exhibit 10.34 Certain identified information has been excluded from this exhibit because it is both not material and is the type that the registrant treats as private or confidential. Information that was omitted has been noted in this document with a placeholder identified by the mark “[***]”. FIFTH AMENDMENT TO LICENSE AGREEMENT THIS FIFTH AMENDMENT TO LICENSE AGREEMENT (this “Fifth Amendment”),

July 21, 2025 EX-10.33

Fourth Amendment to License Agreement, dated November 1, 2008 among Ocugen, Inc. and Angiotech Pharmaceuticals (US), Inc. and Angiodevice International GmbH.

Exhibit 10.33 Certain identified information has been excluded from this exhibit because it is both not material and is the type that the registrant treats as private or confidential. Information that was omitted has been noted in this document with a placeholder identified by the mark “[***]”. FOURTH AMENDMENT TO LICENSE AGREEMENT THIS FOURTH AMENDMENT TO LICENSE AGREEMENT (this “Fourth Amendment

July 21, 2025 EX-10.43

Asset Contribution Agreement, dated June 19, 2025, by and between Ocugen, Inc. and OrthoCellix, Inc.

Exhibit 10.43 ASSET CONTRIBUTION AGREEMENT This Asset Contribution Agreement (this “Asset Contribution Agreement”), dated as of June 19, 2025, is by and between Ocugen, Inc., a Delaware corporation (“Ocugen”), and OrthoCellix, Inc., a Delaware corporation (“OrthoCellix”). WHEREAS, pursuant to this Asset Contribution Agreement, Ocugen desires to contribute, assign and convey to OrthoCellix, and Ort

July 21, 2025 EX-10.30

Amendment to License Agreement, dated August 31, 2007 among Ocugen, Inc. and Angiotech Pharmaceuticals (US), Inc. and Angiodevice International GmbH.

Exhibit 10.30 Certain identified information has been excluded from this exhibit because it is both not material and is the type that the registrant treats as private or confidential. Information that was omitted has been noted in this document with a placeholder identified by the mark “[***]”. AMENDMENT TO LICENSE AGREEMENT (1st Amendment) This Amendment to License Agreement, effective August 31,

July 21, 2025 EX-10.40

License and Commercialization Agreement, dated December 21, 2017 between Ocugen, Inc. and MEDINET Co., Ltd.

EXHIBIT 10.40 Certain identified information has been excluded from this exhibit because it is both not material and is the type that the registrant treats as private or confidential. Information that was omitted has been noted in this document with a placeholder identified by the mark “[***]”. LICENSE AND COMMERCIALIZATION AGREEMENT THIS LICENSE AND COMMERCIALIZATION AGREEMENT (this “Agreement”)

July 21, 2025 EX-10.39

First Amendment to License Agreement, dated May 9, 2016, between Ocugen, Inc. and Purpose Co., Ltd., f/k/a Takagi Sangyo Co. Ltd.

Exhibit 10.39 Certain identified information has been excluded from this exhibit because it is both not material and is the type that the registrant treats as private or confidential. Information that was omitted has been noted in this document with a placeholder identified by the mark “[***]”. FIRST AMENDMENT TO AGREEMENT This First Amendment to the Agreement (this “First Amendment”) effective as

July 21, 2025 EX-10.35

Reinstatement Agreement and Sixth Amendment to License Agreement, dated February 8, 2011 among Ocugen, Inc. and Angiotech Pharmaceuticals (US), Inc. and Angiodevice International GmbH.

Exhibit 10.35 Certain identified information has been excluded from this exhibit because it is both not material and is the type that the registrant treats as private or confidential. Information that was omitted has been noted in this document with a placeholder identified by the mark “[***]”. REINSTATEMENT AGREEMENT AND SIXTH AMENDMENT TO LICENSE AGREEMENT THIS REINSTATEMENT AGREEMENT AND SIXTH

July 21, 2025 EX-10.32

Third Amendment to License Agreement, dated April 15, 2008 among Ocugen and Angiotech Pharmaceuticals (US), Inc. and Angiodevice International GmbH.

Exhibit 10.32 Certain identified information has been excluded from this exhibit because it is both not material and is the type that the registrant treats as private or confidential. Information that was omitted has been noted in this document with a placeholder identified by the mark “[***]”. THIRD AMENDMENT TO LICENSE AGREEMENT THIS THIRD AMENDMENT TO LICENSE AGREEMENT (this “Third Amendment”),

July 21, 2025 S-4

As filed with the Securities and Exchange Commission on July 21, 2025

Table of Contents As filed with the Securities and Exchange Commission on July 21, 2025 Registration No.

July 21, 2025 EX-99.1

Consent of Karthik Musunuri to serve as a director of Carisma Therapeutics Inc., to be renamed OrthoCellix, Inc.

Exhibit 99.1 Consent to be Named as a Director Carisma Therapeutics Inc. is filing a Registration Statement on Form S-4 (the “Registration Statement”) with the Securities and Exchange Commission under the Securities Act of 1933, as amended (the “Securities Act”). In connection therewith, I hereby consent, pursuant to Rule 438 of the Securities Act, to being named in the Registration Statement and

July 21, 2025 EX-10.36

Seventh Amendment to License Agreement, dated March 31, 2011 among Ocugen, Inc. and Angiotech Pharmaceuticals (US), Inc. and Angiodevice International GmbH.

Exhibit 10.36 Certain identified information has been excluded from this exhibit because it is both not material and is the type that the registrant treats as private or confidential. Information that was omitted has been noted in this document with a placeholder identified by the mark “[***]”. SEVENTH AMENDMENT TO LICENSE AGREEMENT THIS SEVENTH AMENDMENT TO LICENSE AGREEMENT (this “Seventh Amendm

July 21, 2025 EX-21.1

Subsidiaries of the Carisma Therapeutics Inc.

Exhibit 21.1 SUBSIDIARIES OF CARISMA THERAPEUTICS INC. Legal Name Jurisdiction of Incorporation Azalea Merger Sub, Inc. Delaware, U.S. CTx Operations, Inc. Delaware, U.S. CARISMA Therapeutics S.à r.l. Luxembourg

July 15, 2025 8-K

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): July 9, 2025 Carisma Therapeutics

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): July 9, 2025 Carisma Therapeutics Inc. (Exact Name of Registrant as Specified in its Charter) Delaware 001-36296 26-2025616 (State or other jurisdiction of incorporation) (Commission

July 15, 2025 425

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): July 9, 2025 Carisma Therapeutics

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): July 9, 2025 Carisma Therapeutics Inc. (Exact Name of Registrant as Specified in its Charter) Delaware 001-36296 26-2025616 (State or other jurisdiction of incorporation) (Commission

July 7, 2025 DEF 14A

UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 SCHEDULE 14A Proxy Statement Pursuant to Section 14(a) of the Securities Exchange Act of 1934 (Amendment No.   )

TABLE OF CONTENTS UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 SCHEDULE 14A Proxy Statement Pursuant to Section 14(a) of the Securities Exchange Act of 1934 (Amendment No.   ) Filed by the Registrant ☒ Filed by a Party other than the Registrant ☐ Check the appropriate box: ☐ Preliminary Proxy Statement ☐ Confidential, for Use of the Commission Only (as permitted by Rule

June 27, 2025 PRE 14A

UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 SCHEDULE 14A Proxy Statement Pursuant to Section 14(a) of the Securities Exchange Act of 1934 (Amendment No.   )

TABLE OF CONTENTS UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 SCHEDULE 14A Proxy Statement Pursuant to Section 14(a) of the Securities Exchange Act of 1934 (Amendment No.   ) Filed by the Registrant ☒ Filed by a Party other than the Registrant ☐ Check the appropriate box: ☒ Preliminary Proxy Statement ☐ Confidential, for Use of the Commission Only (as permitted by Rule

June 25, 2025 425

Filed by Carisma Therapeutics Inc.

Filed by Carisma Therapeutics Inc. pursuant to Rule 425 under the Securities Act of 1933 and deemed filed pursuant to Rule 14a-12 under the Securities Exchange Act of 1934 Subject Company: Carisma Therapeutics Inc. Commission File No.: 001-36296 Date: June 24, 2025 This filing relates to the proposed transaction pursuant to the terms of that certain Agreement and Plan of Merger (the “Merger Agreem

June 23, 2025 EX-99.1

Carisma Therapeutics and OrthoCellix Enter into Definitive Merger Agreement to Create Company Focused on Regenerative Cell Therapies for Orthopedic Diseases

Exhibit 99.1 Carisma Therapeutics and OrthoCellix Enter into Definitive Merger Agreement to Create Company Focused on Regenerative Cell Therapies for Orthopedic Diseases - Proposed reverse merger with OrthoCellix, a wholly-owned subsidiary of Ocugen, to create Nasdaq-listed, late clinical-stage regenerative cell therapy company with a first-in-class technology platform, focused on orthopedic disea

June 23, 2025 425

Filed by Carisma Therapeutics Inc.

Filed by Carisma Therapeutics Inc. pursuant to Rule 425 under the Securities Act of 1933 and deemed filed pursuant to Rule 14a-12 under the Securities Exchange Act of 1934 Subject Company: Carisma Therapeutics Inc. Commission File No.: 001-36296 Date: June 23, 2025 This filing relates to the proposed transaction pursuant to the terms of that certain Agreement and Plan of Merger (the “Merger Agreem

June 23, 2025 EX-2.1

Agreement and Plan of Merger, dated as of June 22, 2025, by and among Carisma Therapeutics Inc., OrthoCellix, Inc., Azalea Merger Sub, Inc. and Ocugen, Inc.

Exhibit 2.1 Execution AGREEMENT AND PLAN OF MERGER by and among CARISMA THERAPEUTICS INC., AZALEA MERGER SUB, INC., ORTHOCELLIX, INC. and OCUGEN, INC. Dated as of June 22, 2025 TABLE OF CONTENTS Page Article I DEFINITIONS & INTERPRETATIONS 3 Section 1.1          Certain Definitions 3 Section 1.2         Interpretation 11 Section 1.3 Currency 11 Article II THE MERGER 11 Section 2.1 Formation of Mer

June 23, 2025 EX-10.4

Form of Lock-Up Agreement

Exhibit 10.4 Lock-Up Agreement [●], 2025 Ladies and Gentlemen: The undersigned (the “Stockholder”) understands that: (i) Carisma therapeutics Inc., a Delaware corporation (“Parent”), has entered into an Agreement and Plan of Merger, dated as of [●], 2025 (as such agreement may be amended, restated, amended and restated or otherwise modified from time to time, the “Merger Agreement”), with Orthocel

June 23, 2025 EX-10.2

Form of Carisma Support Agreement

Exhibit 10.2 SUPPORT AGREEMENT This Support Agreement (this “Agreement”), is made as of [●], 2025, by and among OrthoCellix, Inc., a Delaware corporation (the “Company”), Ocugen Inc., a Delaware corporation (the “Guarantor”), Carisma Therapeutics, Inc., a Delaware corporation (“Parent”), and the Person set forth on Schedule A hereto (the “Stockholder”). WHEREAS, as of the date hereof, the Stockhol

June 23, 2025 8-K

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): June 22, 2025 Carisma Therapeutic

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): June 22, 2025 Carisma Therapeutics Inc. (Exact Name of Registrant as Specified in its Charter) Delaware 001-36296 26-2025616 (State or other jurisdiction of incorporation) (Commission

June 23, 2025 EX-10.1

Form of Contingent Value Rights Agreement

  Exhibit 10.1   CONTINGENT VALUE RIGHTS AGREEMENT   THIS CONTINGENT VALUE RIGHTS AGREEMENT (this “Agreement”), dated as of [●], 2025, is entered into by and between Carisma Therapeutics Inc., a Delaware corporation (“Parent”), and Computershare Inc. a Delaware corporation (“Computershare”), and its affiliate, Computershare Trust Company, N.A., a federally chartered trust company (collectively, as

June 23, 2025 EX-10.2

Form of Carisma Support Agreement

Exhibit 10.2 SUPPORT AGREEMENT This Support Agreement (this “Agreement”), is made as of [●], 2025, by and among OrthoCellix, Inc., a Delaware corporation (the “Company”), Ocugen Inc., a Delaware corporation (the “Guarantor”), Carisma Therapeutics, Inc., a Delaware corporation (“Parent”), and the Person set forth on Schedule A hereto (the “Stockholder”). WHEREAS, as of the date hereof, the Stockhol

June 23, 2025 EX-99.1

Carisma Therapeutics and OrthoCellix Enter into Definitive Merger Agreement to Create Company Focused on Regenerative Cell Therapies for Orthopedic Diseases

Exhibit 99.1 Carisma Therapeutics and OrthoCellix Enter into Definitive Merger Agreement to Create Company Focused on Regenerative Cell Therapies for Orthopedic Diseases - Proposed reverse merger with OrthoCellix, a wholly-owned subsidiary of Ocugen, to create Nasdaq-listed, late clinical-stage regenerative cell therapy company with a first-in-class technology platform, focused on orthopedic disea

June 23, 2025 EX-10.3

Form of OrthoCellix Support Agreement

Exhibit 10.3 SUPPORT AGREEMENT This Support Agreement (this “Agreement”), is made as of [●], 2025, by and among Orthocellix, Inc., a Delaware corporation (the “Company”), Ocugen, inc., a Delaware corporation (the “Guarantor”), Carisma Therapeutics Inc., a Delaware corporation (“Parent”), and the Person set forth on Schedule A hereto (the “Stockholder”). WHEREAS, as of the date hereof, the Stockhol

June 23, 2025 EX-10.4

Form of Lock-Up Agreement

Exhibit 10.4 Lock-Up Agreement [●], 2025 Ladies and Gentlemen: The undersigned (the “Stockholder”) understands that: (i) Carisma therapeutics Inc., a Delaware corporation (“Parent”), has entered into an Agreement and Plan of Merger, dated as of [●], 2025 (as such agreement may be amended, restated, amended and restated or otherwise modified from time to time, the “Merger Agreement”), with Orthocel

June 23, 2025 EX-2.1

Agreement and Plan of Merger, dated as of June 22, 2025, by and among Carisma Therapeutics Inc., OrthoCellix, Inc., Azalea Merger Sub, Inc. and Ocugen, Inc.

Exhibit 2.1 Execution AGREEMENT AND PLAN OF MERGER by and among CARISMA THERAPEUTICS INC., AZALEA MERGER SUB, INC., ORTHOCELLIX, INC. and OCUGEN, INC. Dated as of June 22, 2025 TABLE OF CONTENTS Page Article I DEFINITIONS & INTERPRETATIONS 3 Section 1.1          Certain Definitions 3 Section 1.2         Interpretation 11 Section 1.3 Currency 11 Article II THE MERGER 11 Section 2.1 Formation of Mer

June 23, 2025 EX-10.1

Form of Contingent Value Rights Agreement

  Exhibit 10.1   CONTINGENT VALUE RIGHTS AGREEMENT   THIS CONTINGENT VALUE RIGHTS AGREEMENT (this “Agreement”), dated as of [●], 2025, is entered into by and between Carisma Therapeutics Inc., a Delaware corporation (“Parent”), and Computershare Inc. a Delaware corporation (“Computershare”), and its affiliate, Computershare Trust Company, N.A., a federally chartered trust company (collectively, as

June 23, 2025 EX-10.3

Form of OrthoCellix Support Agreement

Exhibit 10.3 SUPPORT AGREEMENT This Support Agreement (this “Agreement”), is made as of [●], 2025, by and among Orthocellix, Inc., a Delaware corporation (the “Company”), Ocugen, inc., a Delaware corporation (the “Guarantor”), Carisma Therapeutics Inc., a Delaware corporation (“Parent”), and the Person set forth on Schedule A hereto (the “Stockholder”). WHEREAS, as of the date hereof, the Stockhol

June 23, 2025 425

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): June 22, 2025 Carisma Therapeutic

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): June 22, 2025 Carisma Therapeutics Inc. (Exact Name of Registrant as Specified in its Charter) Delaware 001-36296 26-2025616 (State or other jurisdiction of incorporation) (Commission

June 23, 2025 425

Filed by Carisma Therapeutics Inc.

Filed by Carisma Therapeutics Inc. pursuant to Rule 425 under the Securities Act of 1933 and deemed filed pursuant to Rule 14a-12 under the Securities Exchange Act of 1934 Subject Company: Carisma Therapeutics Inc. Commission File No.: 001-36296 Date: June 23, 2025 This filing relates to the proposed transaction pursuant to the terms of that certain Agreement and Plan of Merger (the “Merger Agreem

June 12, 2025 8-K

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): June 10, 2025 Carisma Therapeutic

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): June 10, 2025 Carisma Therapeutics Inc. (Exact Name of Registrant as Specified in its Charter) Delaware 001-36296 26-2025616 (State or other jurisdiction of incorporation) (Commission

May 13, 2025 10-Q

UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 FORM 10-Q

Table of Contents UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 FORM 10-Q x QUARTERLY REPORT PURSUANT TO SECTION 13 OR 15(d) OF THE SECURITIES EXCHANGE ACT OF 1934 For the quarterly period ended March 31, 2025 OR o TRANSITION REPORT PURSUANT TO SECTION 13 OR 15(d) OF THE SECURITIES EXCHANGE ACT OF 1934 For the transition period from to Commission File Number: 001-36296 Ca

April 29, 2025 EX-3.1

Restated Certificate of Incorporation of Carisma Therapeutics Inc., dated March 7, 2023, as amended

Exhibit 3.1 RESTATED CERTIFICATE OF INCORPORATION OF SESEN BIO, INC. (to be renamed Carisma Therapeutics Inc.) (originally incorporated on February 25, 2008) Sesen Bio, Inc. (the “Corporation”), a corporation organized and existing under and by virtue of the provisions of the General Corporation Law of the State of Delaware (the “General Corporation Law”), does hereby certify as follows: A. The cu

April 29, 2025 10-K/A

UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 FORM 10-K/A (Amendment No. 1)

UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 FORM 10-K/A (Amendment No. 1) (Mark One) x ANNUAL REPORT PURSUANT TO SECTION 13 OR 15(d) OF THE SECURITIES EXCHANGE ACT OF 1934 For the fiscal year ended December 31, 2024 OR o TRANSITION REPORT PURSUANT TO SECTION 13 OR 15(d) OF THE SECURITIES EXCHANGE ACT OF 1934 For the transition period from to Commission File Number: 001-

April 16, 2025 8-K

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): April 10, 2025 Carisma Therapeuti

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): April 10, 2025 Carisma Therapeutics Inc. (Exact Name of Registrant as Specified in its Charter) Delaware 001-36296 26-2025616 (State or other jurisdiction of incorporation) (Commissio

March 31, 2025 EX-19.1

(incorporated by reference to Exhibit 19.1 to the registrant’s Annual Report on Form 10-K (File No. 001-36296) filed on March 31, 2025)

Exhibit 19.1 CARISMA THERAPEUTICS INC. INSIDER TRADING POLICY 1.Background and purpose 1.1 Why Have We Adopted This Policy? The federal securities laws prohibit any member of the Board of Directors (a “Director”), officer (as defined in Rule 16a-1(f) under the Securities Exchange Act of 1934 (the “Exchange Act”), an “executive officer”) or employee of Carisma Therapeutics Inc. (together with its s

March 31, 2025 10-K

UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 FORM 10-K

Table of Contents UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 FORM 10-K (Mark One) x ANNUAL REPORT PURSUANT TO SECTION 13 OR 15(d) OF THE SECURITIES EXCHANGE ACT OF 1934 For the fiscal year ended December 31, 2024 OR o TRANSITION REPORT PURSUANT TO SECTION 13 OR 15(d) OF THE SECURITIES EXCHANGE ACT OF 1934 For the transition period from to Commission File Number: 001-36

March 31, 2025 EX-3.1

Restated Certificate of Incorporation of Carisma Therapeutics Inc., dated March 7, 2023, as amended

Exhibit 3.1 RESTATED CERTIFICATE OF INCORPORATION OF SESEN BIO, INC. (to be renamed Carisma Therapeutics Inc.) (originally incorporated on February 25, 2008) Sesen Bio, Inc. (the “Corporation”), a corporation organized and existing under and by virtue of the provisions of the General Corporation Law of the State of Delaware (the “General Corporation Law”), does hereby certify as follows: A. The cu

March 31, 2025 EX-10.17

2024 Form of Stock Option Agreement under the Carisma Therapeutics Inc. 2014 Amended and Restated Stock Incentive Plan (incorporated by reference to Exhibit 10.17 to the registrant’s Annual Report on Form 10-K (File No. 001-36296) filed on April 1, 2024).

Exhibit 10.17 Carisma Therapeutics Inc. STOCK OPTION AGREEMENT Carisma Therapeutics Inc. (the “Company”) hereby grants the following stock option pursuant to its Amended and Restated 2014 Stock Incentive Plan. The terms and conditions attached hereto are also a part hereof. Notice of Grant Name of optionee (the “Participant”): Grant Date: Incentive Stock Option or Nonstatutory Stock Option: Number

March 31, 2025 S-8

As filed with the Securities and Exchange Commission on March 31, 2025

As filed with the Securities and Exchange Commission on March 31, 2025 Registration No.

March 31, 2025 EX-4.1

Description of the Carisma Therapeutics Inc.’s Securities Registered Pursuant to Section 12 of the Securities Exchange Act of 1934 (incorporated by reference to Exhibit 4.1 to Carisma Therapeutics Inc.’s Annual Report on Form 10-K (File No. 001-36296) filed on March 31, 2025).

Exhibit 4.1 DESCRIPTION OF SECURITIES REGISTERED UNDER SECTION 12 OF THE SECURITIES EXCHANGE ACT OF 1934, AS AMENDED The following description of the securities of Carisma Therapeutics Inc. (“us,” “our,” “we” or the “Company”) registered under Section 12 of the Securities Exchange Act of 1934, as amended (the “Exchange Act”), is intended as a summary only and therefore is not a complete descriptio

March 31, 2025 EX-21.1

(incorporated by reference to Exhibit 21.1 to the registrant’s Annual Report on Form 10-K (File No. 001-36296) filed on March 31, 2025)

Exhibit 21.1 Subsidiaries of the Registrant Name of Subsidiary Jurisdiction of Incorporation •CTx Operations, Inc. •Delaware, U.S. •CARISMA Therapeutics S.à r.l. •Luxembourg

March 31, 2025 EX-97

Compensation Recovery Policy (incorporated by reference to Exhibit 97 to the registrant's Annual Report on Form 10-K (File No. 001-36296) filed on April 1, 2024).

Exhibit 97 CARISMA THERAPEUTICS INC. Dodd-Frank Compensation Recovery Policy This Compensation Recovery Policy (this “Policy”) is adopted by Carisma Therapeutics Inc. (the “Company”) in accordance with Nasdaq Listing Rule 5608 (“Rule 5608”), which implements Rule 10D-1 under the Securities Exchange Act of 1934, as amended (the “Exchange Act”) (as promulgated pursuant to Section 954 of the Dodd-Fra

March 31, 2025 EX-FILING FEES

Filing Fee Table.

Exhibit 107 Calculation of Filing Fee Tables Form S-8 (Form Type) Carisma Therapeutics Inc.

January 13, 2025 8-K

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): January 13, 2025 Carisma Therapeu

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): January 13, 2025 Carisma Therapeutics Inc. (Exact Name of Registrant as Specified in its Charter) Delaware 001-36296 26-2025616 (State or other jurisdiction of incorporation) (Commiss

January 10, 2025 8-K

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): January 6, 2025 Carisma Therapeut

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): January 6, 2025 Carisma Therapeutics Inc. (Exact Name of Registrant as Specified in its Charter) Delaware 001-36296 26-2025616 (State or other jurisdiction of incorporation) (Commissi

December 26, 2024 EX-10.1

Master Services Agreement, dated December 24, 2024, by and between Carisma Therapeutics Inc. and Danforth Global, Inc. and Danforth Advisors, LLC (incorporated by reference to Exhibit 10.1 to the registrant’s Current Report on Form 8-K (File No. 001-36296) filed on December 26, 2024).

Exhibit 10.1 MASTER SERVICES AGREEMENT This Master Services Agreement (the “Agreement”) is made effective as of January 1, 2025 (the “Effective Date”), by and between Carisma Therapeutics Inc., a Delaware corporation, with its principal place of business being 3675 Market Street, Suite 401, Philadelphia, PA 19104 (the “Company”) and Danforth Global, Inc., a Delaware corporation, with its principal

December 26, 2024 8-K

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 24, 2024 Carisma Therape

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 24, 2024 Carisma Therapeutics Inc. (Exact Name of Registrant as Specified in its Charter) Delaware 001-36296 26-2025616 (State or other jurisdiction of incorporation) (Commis

December 9, 2024 8-K

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 7, 2024 Carisma Therapeu

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 7, 2024 Carisma Therapeutics Inc. (Exact Name of Registrant as Specified in its Charter) Delaware 001-36296 26-2025616 (State or other jurisdiction of incorporation) (Commiss

November 7, 2024 8-K

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): November 7, 2024 Carisma Therapeu

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): November 7, 2024 Carisma Therapeutics Inc. (Exact Name of Registrant as Specified in its Charter) Delaware 001-36296 26-2025616 (State or other jurisdiction of incorporation) (Commiss

November 7, 2024 10-Q

UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 FORM 10-Q

Table of Contents UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 FORM 10-Q x QUARTERLY REPORT PURSUANT TO SECTION 13 OR 15(d) OF THE SECURITIES EXCHANGE ACT OF 1934 For the quarterly period ended September 30, 2024 OR o TRANSITION REPORT PURSUANT TO SECTION 13 OR 15(d) OF THE SECURITIES EXCHANGE ACT OF 1934 For the transition period from to Commission File Number: 001-3629

November 7, 2024 EX-99.1

Carisma Therapeutics Reports Third Quarter 2024 Financial Results and Recent Business Highlights Initial results from the Phase 1 study of CT-0525, lead product candidate, expected in the first quarter of 2025 Nomination of a development candidate fo

Exhibit 99.1 Carisma Therapeutics Reports Third Quarter 2024 Financial Results and Recent Business Highlights Initial results from the Phase 1 study of CT-0525, lead product candidate, expected in the first quarter of 2025 Nomination of a development candidate for liver fibrosis program expected in the first quarter of 2025 New preclinical efficacy data from the anti-GPC3 in vivo CAR-M therapy to

October 30, 2024 8-K

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): October 24, 2024 Carisma Therapeu

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): October 24, 2024 Carisma Therapeutics Inc. (Exact Name of Registrant as Specified in its Charter) Delaware 001-36296 26-2025616 (State or other jurisdiction of incorporation) (Commiss

October 11, 2024 8-K

Notice of Delisting or Failure to Satisfy a Continued Listing Rule or Standard; Transfer of Listing

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): October 10, 2024 Carisma Therapeutics Inc. (Exact Name of Registrant as Specified in its Charter) Delaware 001-36296 26-2025616 (State or other jurisdiction of incorporation) (Commiss

August 8, 2024 10-Q

UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 FORM 10-Q

Table of Contents UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 FORM 10-Q x QUARTERLY REPORT PURSUANT TO SECTION 13 OR 15(d) OF THE SECURITIES EXCHANGE ACT OF 1934 For the quarterly period ended June 30, 2024 OR o TRANSITION REPORT PURSUANT TO SECTION 13 OR 15(d) OF THE SECURITIES EXCHANGE ACT OF 1934 For the transition period from to Commission File Number: 001-36296 Car

August 8, 2024 EX-99.1

Carisma Therapeutics Reports Second Quarter 2024 Financial Results and Recent Business Highlights Initial data for CT-0525, lead product candidate for anti-HER2 program, expected by year-end 2024 Nomination of a development candidate for liver fibros

Exhibit 99.1 Carisma Therapeutics Reports Second Quarter 2024 Financial Results and Recent Business Highlights Initial data for CT-0525, lead product candidate for anti-HER2 program, expected by year-end 2024 Nomination of a development candidate for liver fibrosis program expected in the first quarter of 2025 Nominated first in vivo CAR-M development candidate targeting Glypican-3 to treat hepato

August 8, 2024 8-K

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): August 8, 2024 Carisma Therapeuti

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): August 8, 2024 Carisma Therapeutics Inc. (Exact Name of Registrant as Specified in its Charter) Delaware 001-36296 26-2025616 (State or other jurisdiction of incorporation) (Commissio

July 9, 2024 EX-99.1

1 Clinical Activity Observed in HER2 3+ Patients Correlation of target expression and clinical activity supports mechanism of action Change in tumor ctDNA at week 4 based on HER2 status: % change in ctDNA 1 * BOR of SD per RECIST v1.1 HER2 status: HE

Exhibit 99.1 1 Clinical Activity Observed in HER2 3+ Patients Correlation of target expression and clinical activity supports mechanism of action Change in tumor ctDNA at week 4 based on HER2 status: % change in ctDNA 1 * BOR of SD per RECIST v1.1 HER2 status: HER2 2+ HER2 3+ ctDNA : Circulating Tumor DNA; PFS: Progression - Free Survival; Signatera assay used for CtDNA ; 1 From day 8 to week 4 CT

July 9, 2024 8-K

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): July 9, 2024 Carisma Therapeutics

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): July 9, 2024 Carisma Therapeutics Inc. (Exact Name of Registrant as Specified in its Charter) Delaware 001-36296 26-2025616 (State or other jurisdiction of incorporation) (Commission

July 2, 2024 8-K

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): June 26, 2024 Carisma Therapeutic

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): June 26, 2024 Carisma Therapeutics Inc. (Exact Name of Registrant as Specified in its Charter) Delaware 001-36296 26-2025616 (State or other jurisdiction of incorporation) (Commission

July 1, 2024 8-K

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): June 26, 2024 Carisma Therapeutic

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): June 26, 2024 Carisma Therapeutics Inc. (Exact Name of Registrant as Specified in its Charter) Delaware 001-36296 26-2025616 (State or other jurisdiction of incorporation) (Commission

June 27, 2024 8-K

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): June 27, 2024 Carisma Therapeutic

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): June 27, 2024 Carisma Therapeutics Inc. (Exact Name of Registrant as Specified in its Charter) Delaware 001-36296 26-2025616 (State or other jurisdiction of incorporation) (Commission

June 27, 2024 EX-99.1

Development Candidate targets Glypican-3 for the treatment of solid tumors, including hepatocellular carcinoma Nomination triggers a $2 million milestone payment to Carisma

Exhibit 99.1 Carisma Therapeutics Announces Nomination of First In Vivo CAR-M Development Candidate for Hepatocellular Carcinoma Under Collaboration with Moderna Development Candidate targets Glypican-3 for the treatment of solid tumors, including hepatocellular carcinoma Nomination triggers a $2 million milestone payment to Carisma PHILADELPHIA, PA – June 27, 2024 – Carisma Therapeutics Inc. (Nas

June 14, 2024 8-K

Departure of Directors or Certain Officers; Election of Directors; Appointment of Certain Officers; Compensatory Arrangements of Certain Officers

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): June 13, 2024 Carisma Therapeutics Inc. (Exact Name of Registrant as Specified in its Charter) Delaware 001-36296 26-2025616 (State or other jurisdiction of incorporation) (Commission

June 14, 2024 8-K

Submission of Matters to a Vote of Security Holders

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): June 14, 2024 Carisma Therapeutics Inc. (Exact Name of Registrant as Specified in its Charter) Delaware 001-36296 26-2025616 (State or other jurisdiction of incorporation) (Commission

May 28, 2024 SC 13D/A

CARM / Carisma Therapeutics, Inc. / HealthCap VII, L.P. - SC 13D/A Activist Investment

SC 13D/A UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 SCHEDULE 13D/A Under the Securities Exchange Act of 1934 (Amendment No. 3) Carisma Therapeutics Inc. (Name of Issuer) Common Stock, par value $0.001 per share (Title of Class of Securities) 14216R 101 (CUSIP Number) HealthCap VII, L.P. Represented by HealthCap VI GP S.A. 23 Avenue Villamont Lausanne, Switzerland CH-10

May 9, 2024 EX-99.1

Carisma Therapeutics Reports First Quarter 2024 Financial Results and Recent Business Highlights Announced CT-0525 as lead product candidate for anti-HER2 program; initial data expected by year-end 2024 Presented preclinical proof of concept data in

Exhibit 99.1 Carisma Therapeutics Reports First Quarter 2024 Financial Results and Recent Business Highlights Announced CT-0525 as lead product candidate for anti-HER2 program; initial data expected by year-end 2024 Presented preclinical proof of concept data in liver fibrosis at ASGCT; expects to nominate a development candidate in the first quarter of 2025 Presented Regimen Level 1 data from Pha

May 9, 2024 10-Q

UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 FORM 10-Q

Table of Contents UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 FORM 10-Q x QUARTERLY REPORT PURSUANT TO SECTION 13 OR 15(d) OF THE SECURITIES EXCHANGE ACT OF 1934 For the quarterly period ended March 31, 2024 OR o TRANSITION REPORT PURSUANT TO SECTION 13 OR 15(d) OF THE SECURITIES EXCHANGE ACT OF 1934 For the transition period from to Commission File Number: 001-36296 Ca

May 9, 2024 8-K

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 9, 2024 Carisma Therapeutics

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 9, 2024 Carisma Therapeutics Inc. (Exact Name of Registrant as Specified in its Charter) Delaware 001-36296 26-2025616 (State or other jurisdiction of incorporation) (Commission F

April 29, 2024 DEF 14A

UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 SCHEDULE 14A Proxy Statement Pursuant to Section 14(a) of the Securities Exchange Act of 1934 (Amendment No.    )

TABLE OF CONTENTS UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 SCHEDULE 14A Proxy Statement Pursuant to Section 14(a) of the Securities Exchange Act of 1934 (Amendment No.    ) Filed by the Registrant ☒ Filed by a Party other than the Registrant ☐ Check the appropriate box: ☐ Preliminary Proxy Statement ☐ Confidential, for Use of the Commission Only (as permitted by Rule

April 10, 2024 8-K

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): April 10, 2024 Carisma Therapeuti

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): April 10, 2024 Carisma Therapeutics Inc. (Exact Name of Registrant as Specified in its Charter) Delaware 001-36296 26-2025616 (State or other jurisdiction of incorporation) (Commissio

April 10, 2024 EX-99.1

1 CT - 0508 Study 101 Monotherapy Patient Demographics (n=14) Heavily pre - treated pts with HER2 2+/3+ solid tumors Summary of Participant and Tumor Characteristics Characteristic N = 14 Characteristic N = 14 Median age (range), years 58 (45, 81) Tu

Exhibit 99.1 1 CT - 0508 Study 101 Monotherapy Patient Demographics (n=14) Heavily pre - treated pts with HER2 2+/3+ solid tumors Summary of Participant and Tumor Characteristics Characteristic N = 14 Characteristic N = 14 Median age (range), years 58 (45, 81) Tumor Type, n (%) Breast Cancer Esophageal Cancer Salivary Carcinoma Cholangiocarcinoma Ovarian Cancer 8 (57.1) 2 (14.3) 2 (14.3) 1 (7.1) 1

April 1, 2024 8-K

Financial Statements and Exhibits, Results of Operations and Financial Condition

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): April 1, 2024 Carisma Therapeutics Inc. (Exact Name of Registrant as Specified in its Charter) Delaware 001-36296 26-2025616 (State or other jurisdiction of incorporation) (Commission

April 1, 2024 EX-99.1

Carisma Therapeutics Provides Business Update and Reports Fourth Quarter and Full Year 2023 Financial Results Company to prioritize CT-0525 as its anti-HER2 CAR-M product candidate and will cease further development of CT-0508 Other prioritized pipel

Exhibit 99.1 Carisma Therapeutics Provides Business Update and Reports Fourth Quarter and Full Year 2023 Financial Results Company to prioritize CT-0525 as its anti-HER2 CAR-M product candidate and will cease further development of CT-0508 Other prioritized pipeline programs include the Company’s in vivo CAR-M collaboration with Moderna, and research programs including fibrosis Cash and cash equiv

April 1, 2024 EX-10.17

2024 Form of Stock Option Agreement under Carisma Therapeutics Inc. 2014 Amended and Restated Stock Incentive Plan (incorporated by reference to Exhibit 10.17 to the Carisma Therapeutics Inc.’s Annual Report on Form 10-K (File No. 001-36296) filed on April 1, 2024).

Exhibit 10.17 Carisma Therapeutics Inc. STOCK OPTION AGREEMENT Carisma Therapeutics Inc. (the “Company”) hereby grants the following stock option pursuant to its Amended and Restated 2014 Stock Incentive Plan. The terms and conditions attached hereto are also a part hereof. Notice of Grant Name of optionee (the “Participant”): Grant Date: Incentive Stock Option or Nonstatutory Stock Option: Number

April 1, 2024 EX-97

Compensation Recovery Policy (incorporated by reference to Exhibit 97 to the registrant's Annual Report on Form 10-K (File No. 001-36296) filed on April 1, 2024).

Exhibit 97 CARISMA THERAPEUTICS INC. Dodd-Frank Compensation Recovery Policy This Compensation Recovery Policy (this “Policy”) is adopted by Carisma Therapeutics Inc. (the “Company”) in accordance with Nasdaq Listing Rule 5608 (“Rule 5608”), which implements Rule 10D-1 under the Securities Exchange Act of 1934, as amended (the “Exchange Act”) (as promulgated pursuant to Section 954 of the Dodd-Fra

April 1, 2024 10-K

UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 FORM 10-K

Table of Contents UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 FORM 10-K (Mark One) x ANNUAL REPORT PURSUANT TO SECTION 13 OR 15(d) OF THE SECURITIES EXCHANGE ACT OF 1934 For the fiscal year ended December 31, 2023 OR o TRANSITION REPORT PURSUANT TO SECTION 13 OR 15(d) OF THE SECURITIES EXCHANGE ACT OF 1934 For the transition period from to Commission File Number: 001-36

April 1, 2024 EX-21.1

Subsidiaries of the Registrant

Exhibit 21.1 Subsidiaries of the Registrant Name of Subsidiary Jurisdiction of Incorporation •CTx Operations, Inc. •Delaware, U.S. •CARISMA Therapeutics S.à r.l. •Luxembourg

March 13, 2024 SC 13G

CARM / Carisma Therapeutics, Inc. / AbbVie Biotechnology Ltd - SC 13G Passive Investment

UNITED STATES SECURITIES AND EXCHANGE COMMISSION WASHINGTON, D.C. 20549 SCHEDULE 13G Under the Securities Exchange Act of 1934 (Amendment No. )* CARISMA THERAPEUTICS INC. (Name of Issuer) Common Stock, $0.001 par value (Titles of Class of Securities) 14216R101 (CUSIP Number) December 31, 2023 (Date of Event Which Requires Filing of this Statement) Check the appropriate box to designate the rule pu

March 7, 2024 EX-99.1(07)

JOINT FILING AGREEMENT

EX-99.1(07) Exhibit 1.07 JOINT FILING AGREEMENT The undersigned hereby agree that they are filing this statement on Schedule 13D jointly pursuant to Rule 13d-1(k)(1). Each of them is responsible for the timely filing of such Schedule 13D and any amendments thereto, and for the completeness and accuracy of the information concerning such person contained therein; but none of them is responsible for

March 7, 2024 SC 13D/A

CARM / Carisma Therapeutics, Inc. / HealthCap VII, L.P. - SC 13D/A Activist Investment

SC 13D/A UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 SCHEDULE 13D/A Under the Securities Exchange Act of 1934 (Amendment No. 2) Carisma Therapeutics Inc. (Name of Issuer) Common Stock, par value $0.001 per share (Title of Class of Securities) 14216R 101 (CUSIP Number) HealthCap VII, L.P. Represented by HealthCap VI GP S.A. 23 Avenue Villamont Lausanne, Switzerland CH-10

February 13, 2024 SC 13G/A

CARM / Carisma Therapeutics, Inc. / VANGUARD GROUP INC - SCHEDULE 13G/A Passive Investment

SC 13G/A 1 tv0534-carismatherapeuticsin.htm SCHEDULE 13G/A SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 Schedule 13G Under the Securities Exchange Act of 1934 (Amendment No.: 2)* Name of issuer: Carisma Therapeutics Inc Title of Class of Securities: Common Stock CUSIP Number: 14216R101 Date of Event Which Requires Filing of this Statement: December 29, 2023 Check the appropriate box t

February 2, 2024 SC 13G/A

CARM / Carisma Therapeutics, Inc. / Longview Innovation Corp. - SC 13G/A Passive Investment

SC 13G/A UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 SCHEDULE 13G UNDER THE SECURITIES EXCHANGE ACT OF 1934 (Amendment No. 1)* Carisma Therapeutics Inc. (Name of Issuer) Common Stock, $0.001 par value per share (Title of Class of Securities) 14216R 101 (CUSIP Number) December 31, 2023 (Date of Event Which Requires Filing of this Statement) Check the appropriate box to d

January 26, 2024 SC 13D/A

CARM / Carisma Therapeutics, Inc. / TRUSTEES OF THE UNIVERSITY OF PENNSYLVANIA - SC 13D/A Activist Investment

SC 13D/A UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 SCHEDULE 13D Under the Securities Exchange Act of 1934 (Amendment No. 1)* Carisma Therapeutics Inc. (Name of Issuer) Common Stock, par value $0.001 (Title of Class of Securities) 14216R 101 (CUSIP Number) Trustees of the University of Pennsylvania 2929 Walnut Street, Suite 300 Philadelphia, PA 19104 (215) 898-1903 (Na

November 9, 2023 8-K

Financial Statements and Exhibits, Results of Operations and Financial Condition

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): November 9, 2023 Carisma Therapeutics Inc. (Exact Name of Registrant as Specified in its Charter) Delaware 001-36296 26-2025616 (State or other jurisdiction of incorporation) (Commiss

November 9, 2023 EX-99.1

Carisma Therapeutics Reports Third Quarter 2023 Financial Results and Recent Business Highlights Presented updated data from Phase 1 clinical trial of CT-0508 at CAR-TCR Summit, further supporting CAR-M safety, feasibility and mechanism of action Sel

Exhibit 99.1 Carisma Therapeutics Reports Third Quarter 2023 Financial Results and Recent Business Highlights Presented updated data from Phase 1 clinical trial of CT-0508 at CAR-TCR Summit, further supporting CAR-M safety, feasibility and mechanism of action Selected clinical candidate for CT-1119, an anti-mesothelin CAR-Monocyte Presented pre-clinical proof of concept data of in vivo CAR-M, from

November 9, 2023 10-Q

UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 FORM 10-Q

Table of Contents UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 FORM 10-Q x QUARTERLY REPORT PURSUANT TO SECTION 13 OR 15(d) OF THE SECURITIES EXCHANGE ACT OF 1934 For the quarterly period ended September 30, 2023 OR o TRANSITION REPORT PURSUANT TO SECTION 13 OR 15(d) OF THE SECURITIES EXCHANGE ACT OF 1934 For the transition period from to Commission File Number: 001-3629

September 1, 2023 EX-99.2

Lead Program CT-0508 Anti-HER2 CAR-M Phase I Trial 10 CT-0508: HER2 Targeted CAR-Macrophage First-in-class & first-in-human engineered macrophage Cells: Autologous monocyte derived macrophages Vector: Ad5f35 Phenotype: M1 Target: HER2 CAR: 1st Genera

Exhibit 99.2 HARNESSING THE POWER OF ENGINEERED MACROPHAGES Michael Klichinsky, PharmD PhD Co-Founder & Chief Scientific Officer CAR-TCR September 2023 2 Cautionary Note Regarding Forward-Looking Statements Regarding Carisma Statements in this press release about future expectations, plans and prospects, as well as any other statements regarding matters that are not historical facts, may constitut

September 1, 2023 EX-99.1

Carisma Announces Latest Data from Phase 1 Clinical Trial of CT-0508 at 8th Annual CAR-TCR Summit Group 2 data available to date support primary safety and feasibility endpoints of single-day bolus dosing of CT-0508 New translational analyses combini

Exhibit 99.1 Carisma Announces Latest Data from Phase 1 Clinical Trial of CT-0508 at 8th Annual CAR-TCR Summit Group 2 data available to date support primary safety and feasibility endpoints of single-day bolus dosing of CT-0508 New translational analyses combining group 1 & group 2 continue to support CAR-M mechanism of action, demonstrating a correlation between biomarkers and best overall respo

September 1, 2023 8-K

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): September 1, 2023 Carisma Therape

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): September 1, 2023 Carisma Therapeutics Inc. (Exact Name of Registrant as Specified in its Charter) Delaware 001-36296 26-2025616 (State or other jurisdiction of incorporation) (Commis

August 10, 2023 EX-99.1

Carisma Therapeutics Reports Second Quarter 2023 Financial Results and Recent Business Highlights Dosed first patient in Phase 1 clinical trial of CT-0508 in combination with KEYTRUDA® (pembrolizumab) in patients with HER2-overexpressing solid tumors

Exhibit 99.1 Carisma Therapeutics Reports Second Quarter 2023 Financial Results and Recent Business Highlights Dosed first patient in Phase 1 clinical trial of CT-0508 in combination with KEYTRUDA® (pembrolizumab) in patients with HER2-overexpressing solid tumors Nominated additional oncology target as part of the Company’s collaboration with Moderna to develop in-vivo targeted CAR-M therapies Cas

August 10, 2023 8-K

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): August 10, 2023 Carisma Therapeut

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): August 10, 2023 Carisma Therapeutics Inc. (Exact Name of Registrant as Specified in its Charter) Delaware 001-36296 26-2025616 (State or other jurisdiction of incorporation) (Commissi

August 10, 2023 10-Q

UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 FORM 10-Q

Table of Contents UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 FORM 10-Q x QUARTERLY REPORT PURSUANT TO SECTION 13 OR 15(d) OF THE SECURITIES EXCHANGE ACT OF 1934 For the quarterly period ended June 30, 2023 OR o TRANSITION REPORT PURSUANT TO SECTION 13 OR 15(d) OF THE SECURITIES EXCHANGE ACT OF 1934 For the transition period from to Commission File Number: 001-36296 Car

June 9, 2023 8-K

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): June 6, 2023 Carisma Therapeutics

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): June 6, 2023 Carisma Therapeutics Inc. (Exact Name of Registrant as Specified in its Charter) Delaware 001-36296 26-2025616 (State or other jurisdiction of incorporation) (Commission

June 9, 2023 EX-99.1

CARISMA THERAPEUTICS INC. AMENDED AND RESTATED 2014 STOCK INCENTIVE PLAN

Exhibit 99.1 CARISMA THERAPEUTICS INC. AMENDED AND RESTATED 2014 STOCK INCENTIVE PLAN 1. Purpose The purpose of this Amended and Restated 2014 Stock Incentive Plan (the “Plan”) of Carisma Therapeutics Inc. (formerly known as Sesen Bio, Inc.), a Delaware corporation (the “Company”), is to advance the interests of the Company’s stockholders by enhancing the Company’s ability to attract, retain and m

June 9, 2023 EX-3.1

Certificate of Amendment of Carisma Therapeutics Inc., dated June 6, 2023 (incorporated by reference to Exhibit 3.1 to the registrant’s Current Report on Form 8-K (File No. 001-36296) filed on June 9, 2023).

Exhibit 3.1 CERTIFICATE OF AMENDMENT TO RESTATED CERTIFICATE OF INCORPORATION OF CARISMA THERAPEUTICS INC. (Pursuant to Section 242 of the General Corporation Law of the State of Delaware) Carisma Therapeutics Inc. (the “Corporation”), a corporation organized and existing under and by virtue of the provisions of the General Corporation Law of the State of Delaware (the “General Corporation Law”),

May 12, 2023 8-K

Entry into a Material Definitive Agreement, Financial Statements and Exhibits

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 12, 2023 Carisma Therapeutics Inc. (Exact Name of Registrant as Specified in its Charter) Delaware 001-36296 26-2025616 (State or other jurisdiction of incorporation) (Commission

May 12, 2023 8-K

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 11, 2023 Carisma Therapeutics

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 11, 2023 Carisma Therapeutics Inc. (Exact Name of Registrant as Specified in its Charter) Delaware 001-36296 26-2025616 (State or other jurisdiction of incorporation) (Commission

May 12, 2023 POS AM

As filed with the Securities and Exchange Commission on May 12, 2023

As filed with the Securities and Exchange Commission on May 12, 2023 Registration No.

May 12, 2023 EX-1.1

, dated May 12, 2023 (incorporated by reference to Exhibit 1.1 to the registrant’s Current Report on Form 8-K (File No. 001-36296) filed on May 12, 2023).

  Exhibit 1.1   AMENDED AND RESTATED OPEN MARKET SALE AGREEMENTSM   May 12, 2023   JEFFERIES LLC 520 Madison Avenue New York, New York 10022   Ladies and Gentlemen:   Carisma Therapeutics Inc. (formerly Sesen Bio, Inc.), a Delaware corporation (the “Company”), proposes, subject to the terms and conditions stated herein, to issue and sell from time to time through Jefferies LLC, as sales agent and/

May 12, 2023 EX-99.1

Carisma Therapeutics Reports First Quarter 2023 Financial Results and Provides Business Highlights Initiated a Phase 1 Sub-Study of CT-0508 in combination with KEYTRUDA® (pembrolizumab) in patients with HER2-overexpressing solid tumors Expanded clini

Exhibit 99.1 Carisma Therapeutics Reports First Quarter 2023 Financial Results and Provides Business Highlights Initiated a Phase 1 Sub-Study of CT-0508 in combination with KEYTRUDA® (pembrolizumab) in patients with HER2-overexpressing solid tumors Expanded clinical manufacturing capacity through successful technology transfer of CT-0508 Closed merger with Sesen Bio and commenced trading on Nasdaq

May 12, 2023 424B5

Up to $100,000,000 Shares of Common Stock

TABLE OF CONTENTS  Filed Pursuant to Rule 424(b)(5)  Registration Statement No. 333-271295 PROSPECTUS SUPPLEMENT (To Prospectus dated May 2, 2023) Up to $100,000,000 Shares of Common Stock We have entered into an Amended and Restated Open Market Sale AgreementSM, or the Sale Agreement, with Jefferies LLC, or Jefferies, relating to the sale of shares of our common stock, par value $0.001 per share,

May 11, 2023 10-Q

UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 FORM 10-Q

Table of Contents UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 FORM 10-Q ☒QUARTERLY REPORT PURSUANT TO SECTION 13 OR 15(d) OF THE SECURITIES EXCHANGE ACT OF 1934 For the quarterly period ended March 31, 2023 OR ☐TRANSITION REPORT PURSUANT TO SECTION 13 OR 15(d) OF THE SECURITIES EXCHANGE ACT OF 1934 For the transition period from to Commission File Number: 001-36296 Cari

May 11, 2023 EX-10.18

Lease, dated April 22, 2019, by and between Wexford-SCEC 3675 Market Street, LLC and CARISMA Therapeutics Inc. (incorporated by reference to Exhibit 10.18 to the registrant’s Quarterly Report on Form 10-Q (File No. 001-36296) filed on May 11, 2023).

Exhibit 10.18 LEASE by and between WEXFORD-SCEC 3675 MARKET STREET, LLC, a Delaware limited liability company, Landlord and CARISMA THERAPEUTICS INC., a Delaware corporation, Tenant TABLE OF CONTENTS Table of Contents Article Title Page 1. Lease of Premises 1 2. Definitions and Basic Lease Provisions 1 3. Term 4 4. Possession and Term Commencement Date 5 5. Condition of Premises 7 6. Rentable Area

April 28, 2023 CORRESP

CARISMA THERAPEUTICS INC. 3675 Market Street, Suite 200 Philadelphia, PA 19104

CARISMA THERAPEUTICS INC. 3675 Market Street, Suite 200 Philadelphia, PA 19104 April 28, 2023 VIA EDGAR Securities and Exchange Commission Division of Corporation Finance 100 F Street, N.E. Washington, D.C. 20549 Re: Carisma Therapeutics Inc. Registration Statement on Form S-3 File No. 333-271296 Request for Acceleration Ladies and Gentlemen: Pursuant to Rule 461 promulgated under the Securities A

April 28, 2023 DEF 14A

Annual Report on Form 10-K from our definitive proxy statement for the 2023

TABLE OF CONTENTS UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 SCHEDULE 14A Proxy Statement Pursuant to Section 14(a) of the Securities Exchange Act of 1934 (Amendment No.    ) Filed by the Registrant ☒ Filed by a Party other than the Registrant ☐ Check the appropriate box: ☐ Preliminary Proxy Statement ☐ Confidential, for Use of the Commission Only (as permitted by Rule

April 28, 2023 CORRESP

CARISMA THERAPEUTICS INC. 3675 Market Street, Suite 200 Philadelphia, PA 19104

CARISMA THERAPEUTICS INC. 3675 Market Street, Suite 200 Philadelphia, PA 19104 April 28, 2023 VIA EDGAR Securities and Exchange Commission Division of Corporation Finance 100 F Street, N.E. Washington, D.C. 20549 Re: Carisma Therapeutics Inc. Registration Statement on Form S-3 File No. 333-271295 Request for Acceleration Ladies and Gentlemen: Pursuant to Rule 461 promulgated under the Securities A

April 17, 2023 EX-4.5

Form of Senior Note

Exhibit 4.5 Form of Senior Note (FACE OF SECURITY) [Each Global Security shall bear substantially the following legend: UNLESS AND UNTIL IT IS EXCHANGED IN WHOLE OR IN PART FOR SECURITIES IN DEFINITIVE REGISTERED FORM, THIS SECURITY MAY NOT BE TRANSFERRED EXCEPT AS A WHOLE BY THE DEPOSITARY TO A NOMINEE OF THE DEPOSITARY OR BY A NOMINEE OF THE DEPOSITARY TO THE DEPOSITARY OR ANOTHER NOMINEE OF THE

April 17, 2023 EX-4.4

Form of Subordinated Indenture

Exhibit 4.4 CARISMA THERAPEUTICS INC. and Trustee INDENTURE Dated as of SUBORDINATED DEBT SECURITIES CROSS-REFERENCE TABLE 1 Section of Trust Indenture Act of 1939, as amended Section of Indenture 310(a) 6.09 310(b) 6.08 6.10 310(c) Inapplicable 311(a) 6.13 311(b) 6.13 311(c) Inapplicable 312(a) 4.01 4.04 312(b) 4.04(c) 312(c) 4.04(c) 313(a) 4.03 313(b) 4.03 313(c) 4.03 313(d) 4.03 314(a) 4.02 314

April 17, 2023 S-3

As filed with the Securities and Exchange Commission on April 17, 2023

TABLE OF CONTENTS As filed with the Securities and Exchange Commission on April 17, 2023 Registration No.

April 17, 2023 S-3

As filed with the Securities and Exchange Commission on April 17, 2023

TABLE OF CONTENTS As filed with the Securities and Exchange Commission on April 17, 2023 Registration No.

April 17, 2023 EX-FILING FEES

Filing Fee Table

Exhibit 107 Calculation of Filing Fee Tables Form S-3 (Form Type) Carisma Therapeutics Inc.

April 17, 2023 EX-FILING FEES

Filing Fee Table

Exhibit 107 Calculation of Filing Fee Tables Form S-3 (Form Type) Carisma Therapeutics Inc.

April 17, 2023 EX-4.6

Form of Subordinated Note

Exhibit 4.6 Form of Subordinated Note (FACE OF SECURITY) [Each Global Security shall bear substantially the following legend: UNLESS AND UNTIL IT IS EXCHANGED IN WHOLE OR IN PART FOR SECURITIES IN DEFINITIVE REGISTERED FORM, THIS SECURITY MAY NOT BE TRANSFERRED EXCEPT AS A WHOLE BY THE DEPOSITARY TO A NOMINEE OF THE DEPOSITARY OR BY A NOMINEE OF THE DEPOSITARY TO THE DEPOSITARY OR ANOTHER NOMINEE

April 17, 2023 EX-4.3

Form of Senior Indenture

Exhibit 4.3 CARISMA THERAPEUTICS INC.    and Trustee INDENTURE Dated as of SENIOR DEBT SECURITIES CROSS-REFERENCE TABLE1 Section of Trust Indenture Act of 1939, as amended Section of Indenture 310(a) 6.09 310(b) 6.08 6.10 310(c) Inapplicable 311(a) 6.13 311(b) 6.13 311(c) Inapplicable 312(a) 4.01 4.04 312(b) 4.04(c) 312(c) 4.04(c) 313(a) 4.03 313(b) 4.03 313(c) 4.03 313(d) 4.03 314(a) 4.02 314(b)

April 17, 2023 PRE 14A

UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 SCHEDULE 14A Proxy Statement Pursuant to Section 14(a) of the Securities Exchange Act of 1934 (Amendment No.    )

TABLE OF CONTENTS UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 SCHEDULE 14A Proxy Statement Pursuant to Section 14(a) of the Securities Exchange Act of 1934 (Amendment No.    ) Filed by the Registrant ☒ Filed by a Party other than the Registrant ☐ Check the appropriate box: ☒ Preliminary Proxy Statement ☐ Confidential, for Use of the Commission Only (as permitted by Rule

April 4, 2023 8-K/A

UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 FORM 8-K/A (Amendment No. 1) CURRENT REPORT Pursuant to Section 13 or 15(d) of the Securities Exchange Act of 1934 Date of Report (Date of earliest event reported): April 4, 2023

UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 FORM 8-K/A (Amendment No. 1) CURRENT REPORT Pursuant to Section 13 or 15(d) of the Securities Exchange Act of 1934 Date of Report (Date of earliest event reported): April 4, 2023 (March 7, 2023) Carisma Therapeutics Inc. (Exact Name of Registrant as Specified in its Charter) Delaware 001-36296 26-2025616 (State or other jurisd

April 4, 2023 S-8

As filed with the Securities and Exchange Commission on April 4, 2023

As filed with the Securities and Exchange Commission on April 4, 2023 Registration No.

April 4, 2023 EX-FILING FEES

Filing Fee Table.

Exhibit 107 Calculation of Filing Fee Tables Form S-8 (Form Type) Carisma Therapeutics Inc.

April 4, 2023 EX-99.4

Carisma Therapeutics Inc. INDEX TO CONSOLIDATED FINANCIAL STATEMENTS

Exhibit 99.4 Carisma Therapeutics Inc. INDEX TO CONSOLIDATED FINANCIAL STATEMENTS Page Consolidated Financial Statements Report of Independent Registered Public Accounting Firm (KPMG LLP, Philadelphia, PA, Auditor Firm ID: 185) F-2 Consolidated Balance Sheets, December 31, 2022 and 2021 F-3 Consolidated Statements of Operations and Comprehensive Loss, Years Ended December 31, 2022 and 2021 F-4 Con

April 4, 2023 EX-99.6

UNAUDITED PRO FORMA CONDENSED COMBINED FINANCIAL INFORMATION

Exhibit 99.6 UNAUDITED PRO FORMA CONDENSED COMBINED FINANCIAL INFORMATION On March 7, 2023, Sesen Bio consummated the merger with Carisma in accordance with the terms of the Agreement and Plan of Merger Reorganization, dated as of September 20, 2022, as amended by the First Amendment thereto dated as of December 29, 2022 and the Second Amendment thereto dated as of February 13, 2023 (as amended, t

April 4, 2023 EX-99.7

Carisma Therapeutics Reports Fiscal 2022 Financial Results and Recent Business Highlights Closed merger with Sesen Bio and commenced trading on Nasdaq under ticker symbol “CARM” Cash position as of the closing of the merger with Sesen Bio provides an

Exhibit 99.7 Carisma Therapeutics Reports Fiscal 2022 Financial Results and Recent Business Highlights Closed merger with Sesen Bio and commenced trading on Nasdaq under ticker symbol “CARM” Cash position as of the closing of the merger with Sesen Bio provides anticipated operating runway through 2024 PHILADELPHIA – April 4, 2023 – Carisma Therapeutics Inc. (Nasdaq: CARM), a clinical-stage biophar

April 4, 2023 EX-99.5

MANAGEMENT’S DISCUSSION AND ANALYSIS OF FINANCIAL CONDITION AND RESULTS OF OPERATIONS

Exhibit 99.5 MANAGEMENT’S DISCUSSION AND ANALYSIS OF FINANCIAL CONDITION AND RESULTS OF OPERATIONS The following discussion and analysis of our financial condition and results of operations should be read in conjunction with our consolidated financial statements and the related notes which are filed as Exhibit 99.4 to our Current Report on Form 8-K/A. Some of the information contained in this disc

March 22, 2023 SC 13D/A

CARM / Carisma Therapeutics Inc / HealthCap VII, L.P. - CARISMA SCHEDULE 13D/A Activist Investment

UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 Schedule 13D/A Under the Securities Exchange Act of 1934 (Amendment No. 1)* CARISMA THERAPEUTICS INC. (Name of Issuer) Common Stock, par value $0.001 per share (Title of Class of Securities) 14216R 101 (CUSIP Number) HealthCap VII, L.P. Represented by its general partner HealthCap VII GP S.A. 23 Avenue Villamont Lausanne, V8 C

March 17, 2023 SC 13D

CARM / Carisma Therapeutics Inc / TRUSTEES OF THE UNIVERSITY OF PENNSYLVANIA - SC 13D Activist Investment

SC 13D UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 SCHEDULE 13D Under the Securities Exchange Act of 1934 (Amendment No. )* Carisma Therapeutics Inc. (Name of Issuer) Common Stock, par value $0.001 (Title of Class of Securities) 14216R 101 (CUSIP Number) Trustees of the University of Pennsylvania 2929 Walnut Street, Suite 300 Philadelphia, PA 19104 (215) 898-1903 (Name,

March 16, 2023 SC 13G

CARM / Carisma Therapeutics Inc / Longview Innovation Corp. - SC 13G Passive Investment

SC 13G UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 SCHEDULE 13G UNDER THE SECURITIES EXCHANGE ACT OF 1934 (Amendment No. )* Carisma Therapeutics Inc. (Name of Issuer) Common Stock, $0.001 par value per share (Title of Class of Securities) 14216R 101 (CUSIP Number) March 7, 2023 (Date of Event Which Requires Filing of this Statement) Check the appropriate box to designat

March 16, 2023 EX-99.1

JOINT FILING AGREEMENT

EX-99.1 Exhibit 99.1 JOINT FILING AGREEMENT This joint filing agreement (this “Agreement”) is made and entered into as of March 16, 2023, by and among Longview Innovation Corp., IPG Cayman LP, IPG USA SCO LP and CT SPV Investment LP. The parties to this Agreement agree to prepare jointly and file timely (and otherwise to deliver as appropriate) all filings on any Schedule 13D or Schedule 13G, and

March 13, 2023 SC 13G

SESN / Sesen Bio Inc. / ModernaTX, Inc. - SCHEDULE 13G Passive Investment

UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 SCHEDULE 13G Under the Securities Exchange Act of 1934 (Amendment No.)* CARISMA THERAPEUTICS INC. (Name of Issuer) Common Stock, par value $0.001 per share (Title of Class of Securities) 817763105 (CUSIP Number) March 7, 2023 (Date of Event Which Requires Filing of this Statement) Check the appropriate box to designate the rul

March 9, 2023 SC 13D

CARM / Carisma Therapeutics Inc / HealthCap VII, L.P. - HEALTHCAP SCHEDULE 13D Activist Investment

UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 Schedule 13D Under the Securities Exchange Act of 1934 (Amendment No. )* CARISMA THERAPEUTICS INC. (Name of Issuer) Common Stock, par value $0.001 per share (Title of Class of Securities) 14216R 101 (CUSIP Number) HealthCap VII, L.P. Represented by its general partner HealthCap VII GP S.A. 23 Avenue Villamont Lausanne, V8 CH -

March 8, 2023 EX-10.14

2023 Form of Stock Option Agreement under the Carisma Therapeutics Inc. 2014 Amended and Restated Stock Incentive Plan (incorporated by reference to Exhibit 10.14 to Carisma Therapeutics Inc.’s Current Report on Form 8-K (File No. 001-36296) filed on March 8, 2023).

Exhibit 10.14 Carisma Therapeutics Inc. STOCK OPTION AGREEMENT Carisma Therapeutics Inc. (the “Company”) hereby grants the following stock option pursuant to its Amended and Restated 2014 Stock Incentive Plan. The terms and conditions attached hereto are also a part hereof. Notice of Grant Name of optionee (the “Participant”): Grant Date: Incentive Stock Option or Nonstatutory Stock Option: Number

March 8, 2023 EX-10.4

Registration Rights Agreement, dated March 7, 2023 (incorporated by reference to Exhibit 10.4 to the registrant’s Current Report on Form 8-K (File No. 001-36296) filed on March 8, 2023).

Exhibit 10.4 REGISTRATION RIGHTS AGREEMENT THIS REGISTRATION RIGHTS AGREEMENT (this “Agreement”), is made as of the 7th day of March, 2023, by and among CARISMA Therapeutics Inc., a Delaware corporation (“Carisma”), and each of the investors listed on Schedule A hereto, each of which is referred to in this Agreement as an “Investor”. RECITALS WHEREAS, Carisma is party to that certain Agreement and

March 8, 2023 EX-10.5

Contingent Value Rights Agreement, dated March 7, 2023 (incorporated by reference to Exhibit 10.5 to the registrant’s Current Report on Form 8-K (File No. 001-36296) filed on March 8, 2023).

Exhibit 10.5 CONTINGENT VALUE RIGHTS AGREEMENT THIS CONTINGENT VALUE RIGHTS AGREEMENT, dated as of March 7, 2023 (this “Agreement”), is entered into by and among Sesen Bio, Inc., a Delaware corporation (“Parent”), and Computershare Inc. (“Computershare”) and its affiliate, Computershare Trust Company, N.A., together, as the Rights Agent. RECITALS WHEREAS, Parent, Seahawk Merger Sub, Inc., a Delawa

March 8, 2023 EX-99.3

RISK FACTORS

Exhibit 99.3 RISK FACTORS Investing in Carisma Therapeutics Inc., or Carisma, securities involves a high degree of risk. You should carefully consider the risk factors set forth below and under “Risk Factors” in Carisma’s Annual Report on Form 10-K for the year ended December 31, 2022 as updated by our subsequent filings under the Securities Exchange Act of 1934, as amended, or the Exchange Act, b

March 8, 2023 EX-10.10

CARISMA Therapeutics Inc. 2017 Stock Incentive Plan (incorporated by reference to Exhibit 10.10 to the registrant’s Current Report on Form 8-K (File No. 001-36296) filed on March 8, 2023).

Exhibit 10.10 2017 Stock Incentive Plan of CARMA Therapeutics Inc. Table of Contents Page 1. Purpose 1 2. Eligibility 1 3. Administration and Delegation 1 (a) Administration by the Board 1 (b) Appointment of Committees 2 4. Stock Available for Awards 2 (a) Number of Shares 2 (b) Substitute Awards 2 5. Stock Options 2 (a) General 2 (b) Incentive Stock Options 2 (c) Exercise Price 3 (d) Duration of

March 8, 2023 EX-99.1

Carisma Therapeutics Closes Merger with Sesen Bio Shares of Carisma to commence trading on Nasdaq under new ticker symbol “CARM” on March 8, 2023 Resulting cash position of approximately $140 million provides runway through 2024; expected to enable m

Exhibit 99.1 Carisma Therapeutics Closes Merger with Sesen Bio Shares of Carisma to commence trading on Nasdaq under new ticker symbol “CARM” on March 8, 2023 Resulting cash position of approximately $140 million provides runway through 2024; expected to enable multiple clinical readouts across Carisma programs PHILADELPHIA – March 7, 2023 – Carisma Therapeutics Inc., a clinical stage biopharmaceu

March 8, 2023 EX-10.8

Employment Agreement, dated March 7, 2023, by and between Carisma Therapeutics Inc. and Richard Morris (incorporated by reference to Exhibit 10.8 to the registrant’s Current Report on Form 8-K (File No. 001-36296) filed on March 8, 2023).

Exhibit 10.8 Execution Copy EMPLOYMENT AGREEMENT THIS EMPLOYMENT AGREEMENT (the “Agreement”), is made as of March 7, 2023 (the “Effective Date”), by and between Carisma Therapeutics Inc., a Delaware corporation (the “Company”), and Richard Morris (the “Executive”) (together, the “Parties”). RECITALS WHEREAS, the Executive has been employed by CTx Operations, Inc. (f/k/a CARISMA Therapeutics Inc.)

March 8, 2023 EX-14.1

Code of Business Conduct and Ethics of Carisma Therapeutics Inc.

Exhibit 14.1 CARISMA THERAPEUTICS INC. CODE OF BUSINESS CONDUCT AND ETHICS This Code of Business Conduct and Ethics (the “Code”) sets forth legal and ethical standards of conduct for employees, officers and directors of Carisma Therapeutics Inc. (the “Company”). This Code is intended to deter wrongdoing and to promote the conduct of all Company business in accordance with high standards of integri

March 8, 2023 EX-16.1

Letter from Ernst & Young LLP, dated March 7, 2023.

Exhibit 16.1 March 7, 2023 Securities and Exchange Commission 100 F Street N.E. Washington, District of Columbia 20549 Ladies and Gentlemen: We have read item 4.01 on Form 8-K dated March 7, 2023 of Carisma Therapeutics Inc. (formerly known as Sesen Bio, Inc.) and are in agreement with the statements contained in the paragraphs within section (a) therein. We have no basis to agree or disagree with

March 8, 2023 EX-99.2

CARISMA BUSINESS

EX-99.2 20 tm238578d1ex99-2.htm EXHIBIT 99.2 Exhibit 99.2 CARISMA BUSINESS Overview Carisma Therapeutics Inc., or Carisma, is a clinical stage cell therapy company focused on utilizing Carisma’s proprietary macrophage and monocyte cell engineering platform to develop transformative immunotherapies to treat cancer and other serious diseases. Carisma has created a comprehensive cell therapy platform

March 8, 2023 EX-10.12

Form of Incentive Stock Option Agreement under the CARISMA Therapeutics Inc. 2017 Stock Incentive Plan (incorporated by reference to Exhibit 10.12 to the registrant’s Current Report on Form 8-K (File No. 001-36296) filed on March 8, 2023).

  Exhibit 10.12   CARISMA Therapeutics Inc.   Incentive Stock Option Agreement Granted Under 2017 Stock Incentive Plan   1.            Grant of Option.   This Incentive Stock Option Agreement (the “Agreement”) evidences the grant by CARISMA Therapeutics Inc., a Delaware corporation (the “Company”), on [ , 20] (the “Grant Date”) to [], an employee of the Company (the “Participant”), of an option to

March 8, 2023 EX-3.2

Amended and Restated By-Laws of Carisma Therapeutics Inc., dated March 7, 2023 (incorporated by reference to Exhibit 3.2 to the registrant’s Current Report on Form 8-K (File No. 001-36296) filed on March 8, 2023).

Exhibit 3.2 AMENDED AND RESTATED BY-LAWS OF CARISMA THERAPEUTICS INC. TABLE OF CONTENTS Page ARTICLE I STOCKHOLDERS 1 1.1 Place of Meetings 1 1.2 Annual Meeting 1 1.3 Special Meetings 1 1.4 Record Date for Stockholder Meetings 1 1.5 Notice of Meetings 1 1.6 Voting List 2 1.7 Quorum 2 1.8 Adjournments 2 1.9 Voting and Proxies 2 1.10 Action at Meeting 2 1.11 Nomination of Directors 3 1.12 Notice of

March 8, 2023 EX-10.6

Form of Indemnification Agreement for Directors and Officers of Carisma Therapeutics Inc. (incorporated by reference to Exhibit 10.6 to the registrant’s Current Report on Form 8-K (File No. 001-36296) filed on March 8, 2023).

Exhibit 10.6 INDEMNIFICATION AGREEMENT This Indemnification Agreement (“Agreement”) is made as of [ ], 20[ ] by and between Carisma Therapeutics Inc., a Delaware corporation (the “Company”), and [ ] (“Indemnitee”). This Agreement supersedes and replaces any and all previous agreements between the Company and Indemnitee covering the subject matter of this Agreement. RECITALS WHEREAS, the Board of D

March 8, 2023 EX-10.15

Form of Restricted Stock Unit Agreement under the Carisma Therapeutics Inc. 2014 Amended and Restated Stock Incentive Plan (incorporated by reference to Exhibit 10.15 to the registrant’s Current Report on Form 8-K (File No. 001-36296) filed on March 8, 2023).

Exhibit 10.15 Carisma Therapeutics Inc. Restricted Stock Unit Agreement Granted under the Amended and Restated 2014 Stock Incentive Plan Carisma Therapeutics Inc. (the “Company”) hereby grants the following restricted stock units pursuant to its Amended and Restated 2014 Stock Incentive Plan. The terms and conditions attached hereto are also a part hereof and incorporated herein by reference. Noti

March 8, 2023 8-K

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 7, 2023 Carisma Therapeutic

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 7, 2023 Carisma Therapeutics Inc. (Exact Name of Registrant as Specified in its Charter) Delaware 001-36296 26-2025616 (State or other jurisdiction of incorporation) (Commission

March 8, 2023 EX-10.13

Carisma Therapeutics Inc. Amended and Restated 2014 Stock Incentive Plan (incorporated by reference to Exhibit 10.13 to the registrant’s Current Report on Form 8-K (File No. 001-36296) filed on March 8, 2023).

Exhibit 10.13 CARISMA THERAPEUTICS INC. AMENDED AND RESTATED 2014 STOCK INCENTIVE PLAN 1. Purpose The purpose of this Amended and Restated 2014 Stock Incentive Plan (the “Plan”) of Carisma Therapeutics Inc. (formerly known as Sesen Bio, Inc.), a Delaware corporation (the “Company”), is to advance the interests of the Company’s stockholders by enhancing the Company’s ability to attract, retain and

March 8, 2023 EX-3.1

Restated Certificate of Incorporation of Carisma Therapeutics Inc., dated March 7, 2023 (incorporated by reference to Exhibit 3.1 to the registrant’s Current Report on Form 8-K (File No. 001-36296) filed on March 8, 2023).

EX-3.1 2 tm238578d1ex3-1.htm EXHIBIT 3.1 Exhibit 3.1 RESTATED CERTIFICATE OF INCORPORATION OF SESEN BIO, INC. (to be renamed Carisma Therapeutics Inc.) (originally incorporated on February 25, 2008) Sesen Bio, Inc. (the “Corporation”), a corporation organized and existing under and by virtue of the provisions of the General Corporation Law of the State of Delaware (the “General Corporation Law”),

March 8, 2023 EX-10.9

Employment Agreement, dated March 7, 2023, by and between Carisma Therapeutics Inc. and Michael Klichinsky (incorporated by reference to Exhibit 10.9 to the registrant’s Current Report on Form 8-K (File No. 001-36296) filed on March 8, 2023).

Exhibit 10.9 Execution Copy EMPLOYMENT AGREEMENT THIS EMPLOYMENT AGREEMENT (the “Agreement”), is made as of March 7, 2023 (the “Effective Date”), by and between Carisma Therapeutics Inc., a Delaware corporation (the “Company”), and Michael Klichinsky (the “Executive”) (together, the “Parties”). RECITALS WHEREAS, the Executive has been employed by CTx Operations, Inc. (f/k/a CARISMA Therapeutics In

March 8, 2023 EX-10.7

Employment Agreement, dated March 7, 2023, by and between Carisma Therapeutics Inc. and Steven Kelly (incorporated by reference to Exhibit 10.7 to the registrant’s Current Report on Form 8-K (File No. 001-36296) filed on March 8, 2023).

Exhibit 10.7 Execution Copy EMPLOYMENT AGREEMENT THIS EMPLOYMENT AGREEMENT (the “Agreement”), is made as of March 7, 2023 (the “Effective Date”), by and between Carisma Therapeutics Inc., a Delaware corporation (the “Company”), and Steven Kelly (the “Executive”) (together, the “Parties”). RECITALS WHEREAS, the Executive has been employed by CTx Operations, Inc. (f/k/a CARISMA Therapeutics Inc.) (t

March 8, 2023 EX-10.16

Carisma Therapeutics Inc. 2014 Employee Stock Purchase Plan (incorporated by reference to Exhibit 10.16 to the registrant’s Current Report on Form 8-K (File No. 001-36296) filed on March 8, 2023).

Exhibit 10.16 CARISMA THERAPEUTICS INC. AMENDED AND RESTATED 2014 EMPLOYEE STOCK PURCHASE PLAN The purpose of this Amended and Restated 2014 Employee Stock Purchase Plan (this “Plan”) is to provide eligible employees of Carisma Therapeutics Inc. (formerly known as Sesen Bio, Inc.) (the “Company”) and certain of its subsidiaries with opportunities to purchase shares of the Company’s common stock, $

March 8, 2023 EX-10.11

Form of Nonstatutory Stock Option Agreement under the CARISMA Therapeutics Inc. 2017 Stock Incentive Plan (incorporated by reference to Exhibit 10.11 to the registrant’s Current Report on Form 8-K (File No. 001-36296) filed on March 8, 2023).

Exhibit 10.11 CARISMA Therapeutics Inc. Nonstatutory Stock Option Agreement Granted Under 2017 Stock Incentive Plan 1.             Grant of Option. This Nonstatutory Stock Option Agreement (the “Agreement”) evidences the grant by CARISMA Therapeutics Inc., a Delaware corporation (the “Company”), on [ , 20] (the “Grant Date”) to [], an employee, consultant or director of the Company (the “Participa

March 6, 2023 425

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 6, 2023 SESEN BIO, INC. (E

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 6, 2023 SESEN BIO, INC. (Exact name of registrant as specified in its charter) Delaware 001-36296 26-2025616 (State or other jurisdiction of incorporation) (Commission File Num

March 6, 2023 8-K

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 6, 2023 SESEN BIO, INC. (E

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 6, 2023 SESEN BIO, INC. (Exact name of registrant as specified in its charter) Delaware 001-36296 26-2025616 (State or other jurisdiction of incorporation) (Commission File Num

March 2, 2023 8-K

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 2, 2023 SESEN BIO, INC. (E

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 2, 2023 SESEN BIO, INC. (Exact name of registrant as specified in its charter) Delaware 001-36296 26-2025616 (State or other jurisdiction of incorporation) (Commission File Num

March 2, 2023 EX-99.1

Sesen Bio Stockholders Approve Merger with Carisma Therapeutics Declares Special Dividend in the Aggregate of $75 Million Approximately 88% Voted in Favor of the Merger at the Special Meeting Merger on Track to Close on March 7, 2023 CAMBRIDGE, Mass.

ex991sesnspecialmeetingr Sesen Bio Stockholders Approve Merger with Carisma Therapeutics Declares Special Dividend in the Aggregate of $75 Million Approximately 88% Voted in Favor of the Merger at the Special Meeting Merger on Track to Close on March 7, 2023 CAMBRIDGE, Mass.

March 2, 2023 EX-3.1

Certificate of Amendment to the Restated Certificate of Incorporation of Sesen Bio, Inc., dated March 2, 2023

ex31conformedforedgar-pr CERTIFICATE OF AMENDMENT TO THE RESTATED CERTIFICATE OF INCORPORATION OF SESEN BIO, INC.

February 28, 2023 8-K

Financial Statements and Exhibits, Results of Operations and Financial Condition

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): February 28, 2023 SESEN BIO, INC. (Exact name of registrant as specified in its charter) Delaware 001-36296 26-2025616 (State or other jurisdiction of incorporation) (Commission File

February 28, 2023 EX-99.1

Sesen Bio Reports Fourth Quarter and Full-Year 2022 Financial Results Sesen Bio Board Believes the Pending Merger with Carisma is the Most Value-Maximizing Option for Stockholders Reiterates Support from Several of Sesen Bio’s Largest Stockholders an

a202302284q2022earnings Sesen Bio Reports Fourth Quarter and Full-Year 2022 Financial Results Sesen Bio Board Believes the Pending Merger with Carisma is the Most Value-Maximizing Option for Stockholders Reiterates Support from Several of Sesen Bio’s Largest Stockholders and Two Leading Independent Proxy Advisors Sesen Bio Board Unanimously Recommends All Stockholders Vote “FOR” Transaction Ahead of March 2, 2023 Special Meeting of Stockholders CAMBRIDGE, Mass.

February 28, 2023 EX-21.1

Subsidiaries of Sesen Bio, Inc.

EXHIBIT 21.1 Subsidiaries of Sesen Bio, Inc. Subsidiary Jurisdiction of Incorporation Viventia Bio Inc. Province of Ontario, Canada Viventia Bio USA Inc. Province of Ontario, Canada Seahawk Merger Sub, Inc. Delaware

February 28, 2023 425

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): February 28, 2023 SESEN BIO, INC

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): February 28, 2023 SESEN BIO, INC. (Exact name of registrant as specified in its charter) Delaware 001-36296 26-2025616 (State or other jurisdiction of incorporation) (Commission File

February 28, 2023 10-K

UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 FORM 10-K

UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 FORM 10-K (Mark One) ☒ ANNUAL REPORT PURSUANT TO SECTION 13 OR 15(d) OF THE SECURITIES EXCHANGE ACT OF 1934 For the fiscal year ended December 31, 2022 or ☐ TRANSITION REPORT PURSUANT TO SECTION 13 OR 15(d) OF THE SECURITIES EXCHANGE ACT OF 1934 For the transition period from to Commission File Number: 001-36296 Sesen Bio, Inc

February 28, 2023 EX-99.1

Sesen Bio Reports Fourth Quarter and Full-Year 2022 Financial Results Sesen Bio Board Believes the Pending Merger with Carisma is the Most Value-Maximizing Option for Stockholders Reiterates Support from Several of Sesen Bio’s Largest Stockholders an

EX-99.1 2 a202302284q2022earnings.htm EX-99.1 Sesen Bio Reports Fourth Quarter and Full-Year 2022 Financial Results Sesen Bio Board Believes the Pending Merger with Carisma is the Most Value-Maximizing Option for Stockholders Reiterates Support from Several of Sesen Bio’s Largest Stockholders and Two Leading Independent Proxy Advisors Sesen Bio Board Unanimously Recommends All Stockholders Vote “F

February 27, 2023 425

Maximizing Value for Sesen Bio Stockholders + Proxy Advisory & Stockholder Support Cutting-Edge Immunotherapy Platform with Long-Term Upside Opportunity Substantial & Immediate Cash Value, Meaningfully Better Than the Alternative STEVEN KELLY Preside

425 1 form425-sesncarminfograp.htm 425 Maximizing Value for Sesen Bio Stockholders + Proxy Advisory & Stockholder Support Cutting-Edge Immunotherapy Platform with Long-Term Upside Opportunity Substantial & Immediate Cash Value, Meaningfully Better Than the Alternative STEVEN KELLY President & CEO MICHAEL KLICHINSKY, PHD Co-Founder & Chief Scientific Officer BML INVESTMENT PARTNERS, L.P. (4.1% Owne

February 27, 2023 425

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): February 24, 2023 SESEN BIO, INC

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): February 24, 2023 SESEN BIO, INC. (Exact name of registrant as specified in its charter) Delaware 001-36296 26-2025616 (State or other jurisdiction of incorporation) (Commission File

February 27, 2023 8-K

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): February 24, 2023 SESEN BIO, INC

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): February 24, 2023 SESEN BIO, INC. (Exact name of registrant as specified in its charter) Delaware 001-36296 26-2025616 (State or other jurisdiction of incorporation) (Commission File

February 22, 2023 425

Dear Sesen Bio Stockholders: On behalf of the entire Carisma management team and board of directors, I want to tell you how excited we are about the pending merger with Sesen Bio. We believe we will do great things together to revolutionize the way w

form425-carismastockhold Dear Sesen Bio Stockholders: On behalf of the entire Carisma management team and board of directors, I want to tell you how excited we are about the pending merger with Sesen Bio.

February 21, 2023 425

Leading Independent Proxy Advisory Firm Glass Lewis Joins ISS in Recommending that Sesen Bio Stockholders Vote “FOR” All Proposals to Approve Pending Merger With Carisma Positive Recommendations Underscore that Carisma Merger Maximizes Value for Sese

Filed by Sesen Bio, Inc. Pursuant to Rule 425 under the Securities Act of 1933 and deemed filed pursuant to Rule 14a-6(b) under the Securities Exchange Act of 1934 Subject Company: Sesen Bio, Inc. Commission File No.: 001-36296 Leading Independent Proxy Advisory Firm Glass Lewis Joins ISS in Recommending that Sesen Bio Stockholders Vote “FOR” All Proposals to Approve Pending Merger With Carisma Po

February 21, 2023 425

SESEN BIO AND CARISMA THERAPEUTICS FIRESIDE CHAT

Filed by Sesen Bio, Inc. Pursuant to Rule 425 under the Securities Act of 1933 and deemed filed pursuant to Rule 14a-6(b) under the Securities Exchange Act of 1934 Subject Company: Sesen Bio, Inc. Commission File No.: 001-36296 SESEN BIO AND CARISMA THERAPEUTICS FIRESIDE CHAT CALL DETAILS Date: February 21, 2023 Time: 8:00 am ET PARTICIPANTS Dr. Thomas R. Cannell, Sesen Bio – President, CEO and Di

February 17, 2023 425

Maximizing Value for Sesen Bio Stockholders February 2023 Filed by Sesen Bio, Inc. Pursuant to Rule 425 under the Securities Act of 1933 and deemed filed pursuant to Rule 14a-6(b) under the Securities Exchange Act of 1934 Subject Company: Sesen Bio,

investorupdatepresentati Maximizing Value for Sesen Bio Stockholders February 2023 Filed by Sesen Bio, Inc.

February 17, 2023 425

Filed by Sesen Bio, Inc. Pursuant to Rule 425 under the Securities Act of 1933 and deemed filed pursuant to Rule 14a-6(b) under the Securities Exchange Act of 1934 Subject Company: Sesen Bio, Inc. Commission File No.: 001-36296

Filed by Sesen Bio, Inc. Pursuant to Rule 425 under the Securities Act of 1933 and deemed filed pursuant to Rule 14a-6(b) under the Securities Exchange Act of 1934 Subject Company: Sesen Bio, Inc. Commission File No.: 001-36296

February 17, 2023 425

$75M Special Cash Dividend Direct and immediate value ($0.36/share1) 24.2% Stake in $352M2 Combined Company Sesen Bio stockholders to receive ownership stake in Carisma, a well-funded company developing groundbreaking therapies for a wide range of ca

425 1 sesncarmtransactioninfog.htm 425 $75M Special Cash Dividend Direct and immediate value ($0.36/share1) 24.2% Stake in $352M2 Combined Company Sesen Bio stockholders to receive ownership stake in Carisma, a well-funded company developing groundbreaking therapies for a wide range of cancers ($0.38/share3). This includes $30M of additional incremental financing from Carisma’s key investors (Abbv

February 17, 2023 425

Further increased special dividend to $75 million. We have increased the expected one-time special cash dividend to $75 million, $0.36 per share1. Since we first announced the merger in September 2022, we have increased the special cash dividend by $

sesnstockholderupdatelet Further increased special dividend to $75 million. We have increased the expected one-time special cash dividend to $75 million, $0.36 per share1. Since we first announced the merger in September 2022, we have increased the special cash dividend by $50 million, from the original dividend amount of up to $25 million. This is a significant amount of upfront cash that stockho

February 16, 2023 424B3

SUPPLEMENT DATED FEBRUARY 16, 2023 (TO PROXY STATEMENT/PROSPECTUS DATED JANUARY 19, 2023) AMENDED MERGER PROPOSAL YOUR VOTE IS VERY IMPORTANT

424B3 1 tm236507-3424b3.htm 424B3 TABLE OF CONTENTS  Filed pursuant to Rule 424(b)(3)  Registration No. 333-267891 SUPPLEMENT DATED FEBRUARY 16, 2023 (TO PROXY STATEMENT/PROSPECTUS DATED JANUARY 19, 2023) AMENDED MERGER PROPOSAL YOUR VOTE IS VERY IMPORTANT To the stockholders of Sesen Bio, Inc. and CARISMA Therapeutics Inc.: On or about January 24, 2023, Sesen Bio, Inc., or Sesen Bio, mailed you a

February 16, 2023 425

Sesen Bio to Host Webcast with Carisma Therapeutics to Discuss Pending Merger

Filed by Sesen Bio, Inc. Pursuant to Rule 425 under the Securities Act of 1933 and deemed filed pursuant to Rule 14a-6(b) under the Securities Exchange Act of 1934 Subject Company: Sesen Bio, Inc. Commission File No.: 001-36296 Sesen Bio to Host Webcast with Carisma Therapeutics to Discuss Pending Merger CAMBRIDGE, Mass.– February 16, 2023 – Sesen Bio, Inc. (Nasdaq: SESN) today announced that memb

February 16, 2023 425

Leading Independent Proxy Advisory Firm ISS Recommends Sesen Bio Stockholders Vote “FOR” All Proposals at March 2 Special Meeting Report Highlights Compelling Strategic Rationale, Estimated Potential Value to Shareholders of $0.88 per Share and Downs

Filed by Sesen Bio, Inc. Pursuant to Rule 425 under the Securities Act of 1933 and deemed filed pursuant to Rule 14a-6(b) under the Securities Exchange Act of 1934 Subject Company: Sesen Bio, Inc. Commission File No.: 001-36296 Leading Independent Proxy Advisory Firm ISS Recommends Sesen Bio Stockholders Vote “FOR” All Proposals at March 2 Special Meeting Report Highlights Compelling Strategic Rat

February 15, 2023 SC 13D/A

SESN / Sesen Bio Inc / Radoff Bradley Louis - AMENDMENT NO. 4 TO THE SCHEDULE 13D Activist Investment

UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 SCHEDULE 13D (Rule 13d-101) INFORMATION TO BE INCLUDED IN STATEMENTS FILED PURSUANT TO § 240.13d-1(a) AND AMENDMENTS THERETO FILED PURSUANT TO § 240.13d-2(a) (Amendment No. 4)1 Sesen Bio, Inc. (Name of Issuer) Common Stock, $0.001 par value per share (Title of Class of Securities) 817763105 (CUSIP Number) BRADLEY L. RADOFF 272

February 15, 2023 425

BML, One of Sesen Bio’s Top Stockholders, Announces Support for Pending Merger with Carisma Therapeutics Sesen Bio Board Unanimously Recommends All Stockholders to Vote “FOR” the Value Maximizing Merger on the WHITE Proxy Card Today CAMBRIDGE, Mass.

bmlsupportreleasevf0215 BML, One of Sesen Bio’s Top Stockholders, Announces Support for Pending Merger with Carisma Therapeutics Sesen Bio Board Unanimously Recommends All Stockholders to Vote “FOR” the Value Maximizing Merger on the WHITE Proxy Card Today CAMBRIDGE, Mass.

February 14, 2023 EX-99.1

Sesen Bio and Carisma Therapeutics Announce Increased Special Cash Dividend and Stockholder Support for Pending Merger Amend Merger Agreement to Increase Expected Special Cash Dividend to $75 Million and Extend Contingent Value Right for Vicineum to

EXHIBIT 99.1 FOR IMMEDIATE RELEASE Sesen Bio and Carisma Therapeutics Announce Increased Special Cash Dividend and Stockholder Support for Pending Merger Amend Merger Agreement to Increase Expected Special Cash Dividend to $75 Million and Extend Contingent Value Right for Vicineum to March 31, 2027 Bradley L. Radoff and Michael Torok to Vote Shares in Support of Transaction Michael Torok to Join C

February 14, 2023 EX-2.1

Second Amendment to Agreement and Plan of Merger and Reorganization, dated as of February 13, 2023, by and among Sesen Bio, Inc., Seahawk Merger Sub, Inc., and Carisma. Incorporated by reference to Exhibit 2.1 to our Current Report on Form 8-K filed on February 14, 2023 (File No. 001-36296).

EX-2.1 2 tm236507d1ex2-1.htm EXHIBIT 2.1 EXHIBIT 2.1 SECOND AMENDMENT TO AGREEMENT AND PLAN OF MERGER AND REORGANIZATION THIS SECOND AMENDMENT TO AGREEMENT AND PLAN OF MERGER AND REORGANIZATION (this “Second Amendment”) is made and entered into as of February 13, 2023, by and among SESEN BIO, INC., a Delaware corporation (“Parent”), SEAHAWK MERGER SUB, INC., a Delaware corporation and wholly-owned

February 14, 2023 EX-10.1

Voting and Support Agreement, dated February 13, 2023, by and among the Radoff Family Foundation, Bradley L. Radoff, JEC II Associates, LLC, the K. Peter Heiland 2008 Irrevocable Trust, Michael Torok, CARISMA Therapeutics, Inc. and Sesen Bio, Inc.

EX-10.1 3 tm236507d1ex10-1.htm EXHIBIT 10.1 EXHIBIT 10.1 VOTING AND SUPPORT AGREEMENT This VOTING AND SUPPORT AGREEMENT (this “Support Agreement”) is entered into as of February 13, 2023, among CARISMA Therapeutics Inc., a Delaware corporation (the “Company”), Sesen Bio, Inc., a Delaware corporation (“Parent”), and the undersigned stockholders (collectively, the “Stockholders,” and each, a “Stockh

February 14, 2023 8-K

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): February 13, 2023 SESEN BIO, INC.

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): February 13, 2023 SESEN BIO, INC. (Exact name of Registrant as Specified in Its Charter) Delaware 001-36296 26-2025616 (State or Other Jurisdiction (Commission File Number) (IRS Emplo

February 14, 2023 S-4MEF

As filed with the Securities and Exchange Commission on February 14, 2023

As filed with the Securities and Exchange Commission on February 14, 2023 Registration No.

February 14, 2023 EX-FILING FEES

Filing Fee Table.

Exhibit 107 Calculation of Filing Fee Tables Form S-4 (Form Type) SESEN BIO, INC. (Exact Name of Registrant as Specified in its Charter) Table 1—Newly Registered and Carry Forward Securities Security Type Security Class Title Fee Calculation or Carry Forward Rule Amount Registered Proposed Maximum Offering Price Per Unit Maximum Aggregate Offering Price Fee Rate Amount of Registration Fee Carry Fo

February 14, 2023 425

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): February 13, 2023 SESEN BIO, INC.

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): February 13, 2023 SESEN BIO, INC. (Exact name of Registrant as Specified in Its Charter) Delaware 001-36296 26-2025616 (State or Other Jurisdiction (Commission File Number) (IRS Emplo

February 14, 2023 EX-99.1

Consent of SVB Securities LLC, financial advisor to Sesen Bio, Inc.

EXHIBIT 99.1 CONSENT OF SVB SECURITIES LLC We hereby consent to the use of our opinion letter dated December 29, 2022 to the Board of Directors of Sesen Bio, Inc., incorporated in the Registration Statement on Form S-4 of Sesen Bio, Inc. to be filed on the date hereof, by reference to the Registration Statement on Form S-4 (Registration No. 333-267891) of Sesen Bio, Inc. declared effective on Janu

February 9, 2023 SC 13G/A

SESN / Sesen Bio Inc / VANGUARD GROUP INC - SCHEDULE 13G/A Passive Investment

SC 13G/A 1 tv01880-sesenbioinc.htm SCHEDULE 13G/A SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 Schedule 13G Under the Securities Exchange Act of 1934 (Amendment No.: 1)* Name of issuer: Sesen Bio Inc. Title of Class of Securities: Common Stock CUSIP Number: 817763105 Date of Event Which Requires Filing of this Statement: December 30, 2022 Check the appropriate box to designate the rul

February 7, 2023 425

Carisma Twitter:

Filed by Sesen Bio, Inc. Pursuant to Rule 425 under the Securities Act of 1933 and deemed filed pursuant to Rule 14a-6(b) under the Securities Exchange Act of 1934 Subject Company: Sesen Bio, Inc. Commission File No.: 001-36296 Carisma Twitter: We are excited to announce another key addition to our SAB, mRNA therapeutics expert and Moderna CSO of External Ventures, Dr. Lin Guey. This appointment f

February 7, 2023 425

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): February 7, 2023 SESEN BIO, INC.

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): February 7, 2023 SESEN BIO, INC. (Exact name of registrant as specified in its charter) Delaware 001-36296 26-2025616 (State or other jurisdiction of incorporation) (Commission File

February 7, 2023 EX-99.1

Carisma Therapeutics Appoints Moderna CSO of External Research Ventures, Lin Guey, to Scientific Advisory Board PHILADELPHIA – February 7, 2023 – Carisma Therapeutics Inc., a clinical stage biopharmaceutical company focused on discovering and develop

exhibit991carismaprguey Carisma Therapeutics Appoints Moderna CSO of External Research Ventures, Lin Guey, to Scientific Advisory Board PHILADELPHIA – February 7, 2023 – Carisma Therapeutics Inc.

February 7, 2023 8-K

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): February 7, 2023 SESEN BIO, INC.

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): February 7, 2023 SESEN BIO, INC. (Exact name of registrant as specified in its charter) Delaware 001-36296 26-2025616 (State or other jurisdiction of incorporation) (Commission File

February 7, 2023 EX-99.1

Carisma Therapeutics Appoints Moderna CSO of External Research Ventures, Lin Guey, to Scientific Advisory Board PHILADELPHIA – February 7, 2023 – Carisma Therapeutics Inc., a clinical stage biopharmaceutical company focused on discovering and develop

exhibit991carismaprguey Carisma Therapeutics Appoints Moderna CSO of External Research Ventures, Lin Guey, to Scientific Advisory Board PHILADELPHIA – February 7, 2023 – Carisma Therapeutics Inc.

February 2, 2023 EX-99.2

Maximizing Value for Sesen Bio Stockholders February 2023

Exhibit 99.2 Maximizing Value for Sesen Bio Stockholders February 2023 Forward - Looking Statements and Additional Disclaimers Forward - Looking Statements Any statements in this communication about future expectations, plans and prospects for Sesen Bio, Inc. ( Sesen Bio), CARISMA Therapeutics Inc. ( Carisma ) or the combined company, Sesen Bio’s, Carisma’s or the combined company’s strategy or fu

February 2, 2023 EX-99.1

Sesen Bio Files Investor Presentation in Connection with Pending Carisma Therapeutics Merger Highlights Board’s Robust Strategic Review Process and Unanimous Determination that Carisma Merger Maximizes Value for Stockholders Urges Stockholders to Vot

EX-99.1 2 tm235275d1ex99-1.htm EXHIBIT 99.1 Exhibit 99.1 Sesen Bio Files Investor Presentation in Connection with Pending Carisma Therapeutics Merger Highlights Board’s Robust Strategic Review Process and Unanimous Determination that Carisma Merger Maximizes Value for Stockholders Urges Stockholders to Vote “FOR” Transaction Ahead of Special Meeting of Stockholders on March 2, 2023 CAMBRIDGE, Mass

February 2, 2023 8-K

Financial Statements and Exhibits, Other Events

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): February 2, 2023 SESEN BIO, INC. (Exact name of Registrant as Specified in Its Charter) Delaware 001-36296 26-2025616 (State or Other Jurisdiction (Commission File Number) (IRS Employ

February 2, 2023 EX-99.2

Maximizing Value for Sesen Bio Stockholders February 2023

Exhibit 99.2 Maximizing Value for Sesen Bio Stockholders February 2023 Forward - Looking Statements and Additional Disclaimers Forward - Looking Statements Any statements in this communication about future expectations, plans and prospects for Sesen Bio, Inc. ( Sesen Bio), CARISMA Therapeutics Inc. ( Carisma ) or the combined company, Sesen Bio’s, Carisma’s or the combined company’s strategy or fu

February 2, 2023 425

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): February 2, 2023 SESEN BIO, INC.

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): February 2, 2023 SESEN BIO, INC. (Exact name of Registrant as Specified in Its Charter) Delaware 001-36296 26-2025616 (State or Other Jurisdiction (Commission File Number) (IRS Employ

February 2, 2023 EX-99.1

Sesen Bio Files Investor Presentation in Connection with Pending Carisma Therapeutics Merger Highlights Board’s Robust Strategic Review Process and Unanimous Determination that Carisma Merger Maximizes Value for Stockholders Urges Stockholders to Vot

EX-99.1 2 tm235275d2ex99-1.htm EXHIBIT 99.1 Exhibit 99.1 Sesen Bio Files Investor Presentation in Connection with Pending Carisma Therapeutics Merger Highlights Board’s Robust Strategic Review Process and Unanimous Determination that Carisma Merger Maximizes Value for Stockholders Urges Stockholders to Vote “FOR” Transaction Ahead of Special Meeting of Stockholders on March 2, 2023 CAMBRIDGE, Mass

February 1, 2023 8-K

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): January 31, 2023 SESEN BIO, INC.

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): January 31, 2023 SESEN BIO, INC. (Exact name of registrant as specified in its charter) Delaware 001-36296 26-2025616 (State or other jurisdiction of incorporation) (Commission File

January 31, 2023 425

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): January 31, 2023 SESEN BIO, INC.

425 1 sesnformcarismapressreleas.htm 425 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): January 31, 2023 SESEN BIO, INC. (Exact name of registrant as specified in its charter) Delaware 001-36296 26-2025616 (State or other jurisdi

January 31, 2023 EX-99.1

Carisma Therapeutics Appoints Leading Solid Tumor Immunotherapy Expert Padmanee Sharma, MD, PhD to Scientific Advisory Board Expansion of Scientific Advisory Board provides additional expertise in development capabilities PHILADELPHIA – January 31, 2

ex991-carsimasharmapres Carisma Therapeutics Appoints Leading Solid Tumor Immunotherapy Expert Padmanee Sharma, MD, PhD to Scientific Advisory Board Expansion of Scientific Advisory Board provides additional expertise in development capabilities PHILADELPHIA – January 31, 2023 – Carisma Therapeutics Inc.

January 31, 2023 425

Carisma Twitter:

Filed by Sesen Bio, Inc. Pursuant to Rule 425 under the Securities Act of 1933 and deemed filed pursuant to Rule 14a-6(b) under the Securities Exchange Act of 1934 Subject Company: Sesen Bio, Inc. Commission File No.: 001-36296 Carisma Twitter: We are excited to announce the appointment of leading solid tumor immunotherapy expert @PamSharmaMDPhD to our Scientific Advisory Board. Learn more on Dr.

January 31, 2023 8-K

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): January 31, 2023 SESEN BIO, INC.

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): January 31, 2023 SESEN BIO, INC. (Exact name of registrant as specified in its charter) Delaware 001-36296 26-2025616 (State or other jurisdiction of incorporation) (Commission File

January 31, 2023 EX-99.1

Carisma Therapeutics Appoints Leading Solid Tumor Immunotherapy Expert Padmanee Sharma, MD, PhD to Scientific Advisory Board Expansion of Scientific Advisory Board provides additional expertise in development capabilities PHILADELPHIA – January 31, 2

ex991-carsimasharmapres Carisma Therapeutics Appoints Leading Solid Tumor Immunotherapy Expert Padmanee Sharma, MD, PhD to Scientific Advisory Board Expansion of Scientific Advisory Board provides additional expertise in development capabilities PHILADELPHIA – January 31, 2023 – Carisma Therapeutics Inc.

January 30, 2023 8-K

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): January 25, 2023 SESEN BIO, INC.

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): January 25, 2023 SESEN BIO, INC. (Exact name of registrant as specified in its charter) Delaware 001-36296 26-2025616 (State or other jurisdiction of incorporation) (Commission File

January 30, 2023 EX-99.1

Sesen Bio Receives NASDAQ Delisting Notice Company Remains Focused on Significant Benefits of Pending Merger with Carisma Delisting Notice Underscores Potential for Corporate Dissolution if Merger is not Approved by Stockholders CAMBRIDGE, Mass. – (B

ex991nasdaqdelistingnoti Sesen Bio Receives NASDAQ Delisting Notice Company Remains Focused on Significant Benefits of Pending Merger with Carisma Delisting Notice Underscores Potential for Corporate Dissolution if Merger is not Approved by Stockholders CAMBRIDGE, Mass.

January 30, 2023 EX-99.1

Sesen Bio Receives NASDAQ Delisting Notice Company Remains Focused on Significant Benefits of Pending Merger with Carisma Delisting Notice Underscores Potential for Corporate Dissolution if Merger is not Approved by Stockholders CAMBRIDGE, Mass. – (B

ex991nasdaqdelistingnoti Sesen Bio Receives NASDAQ Delisting Notice Company Remains Focused on Significant Benefits of Pending Merger with Carisma Delisting Notice Underscores Potential for Corporate Dissolution if Merger is not Approved by Stockholders CAMBRIDGE, Mass.

January 30, 2023 425

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): January 25, 2023 SESEN BIO, INC.

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): January 25, 2023 SESEN BIO, INC. (Exact name of registrant as specified in its charter) Delaware 001-36296 26-2025616 (State or other jurisdiction of incorporation) (Commission File

January 26, 2023 EX-99.1

Investor Group Issues Letter to the Boards of Sesen Bio and Carisma Rejecting Their Apparent Attempt to Purchase Merger Support Discloses Recent Offer to Provide Paid Advisory Roles to Messrs. Radoff and Torok – Major Stockholders of Sesen Bio – in E

Exhibit 99.1 Investor Group Issues Letter to the Boards of Sesen Bio and Carisma Rejecting Their Apparent Attempt to Purchase Merger Support Discloses Recent Offer to Provide Paid Advisory Roles to Messrs. Radoff and Torok – Major Stockholders of Sesen Bio – in Exchange for Their Support of the Proposed Merger of Sesen Bio and Carisma Reiterates Intent to Vote AGAINST the Proposed Merger HOUSTON-(

January 26, 2023 425

Sesen Bio Reiterates Confidence that Pending Merger with Carisma is in Best Interests of Stockholders Company Calls Out Misrepresentations from Investor Group CAMBRIDGE, Mass. – January 26, 2023 – Sesen Bio, Inc. (Nasdaq: SESN) today issued the follo

sesninvestorgrouprespon Sesen Bio Reiterates Confidence that Pending Merger with Carisma is in Best Interests of Stockholders Company Calls Out Misrepresentations from Investor Group CAMBRIDGE, Mass.

January 26, 2023 SC 13D/A

SESN / Sesen Bio Inc / Radoff Bradley Louis - AMENDMENT NO. 3 TO THE SCHEDULE 13D Activist Investment

UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 SCHEDULE 13D (Rule 13d-101) INFORMATION TO BE INCLUDED IN STATEMENTS FILED PURSUANT TO § 240.13d-1(a) AND AMENDMENTS THERETO FILED PURSUANT TO § 240.13d-2(a) (Amendment No. 3)1 Sesen Bio, Inc. (Name of Issuer) Common Stock, $0.001 par value per share (Title of Class of Securities) 817763105 (CUSIP Number) BRADLEY L. RADOFF 272

January 19, 2023 425

Filed by Sesen Bio, Inc. Pursuant to Rule 425 under the Securities Act of 1933 and deemed filed pursuant to Rule 14a-6(b) under the Securities Exchange Act of 1934 Subject Company: Sesen Bio, Inc. Commission File No.: 001-36296 Important Information

Filed by Sesen Bio, Inc. Pursuant to Rule 425 under the Securities Act of 1933 and deemed filed pursuant to Rule 14a-6(b) under the Securities Exchange Act of 1934 Subject Company: Sesen Bio, Inc. Commission File No.: 001-36296 Important Information for Sesen Bio Stockholders Please vote your shares at the Special Meeting of Stockholders to be held on March 2, 2023 at 10:00 A.M. Eastern Time Key q

January 19, 2023 425

Vote FOR the Pending Merger with Carisma Therapeutics Please follow the instructions on the enclosed proxy card to VOTE “FOR” the transaction today. Vote by telephone, internet or mail!Vote “FOR” All Agenda Items Today! Dear Fellow Stockholder, Sesen

Filed by Sesen Bio, Inc. Pursuant to Rule 425 under the Securities Act of 1933 and deemed filed pursuant to Rule 14a-6(b) under the Securities Exchange Act of 1934 Subject Company: Sesen Bio, Inc. Commission File No.: 001-36296 Vote FOR the Pending Merger with Carisma Therapeutics Please follow the instructions on the enclosed proxy card to VOTE “FOR” the transaction today. Vote by telephone, inte

January 19, 2023 425

Sesen Bio Files Definitive Proxy Statement and Mails Letter to Stockholders in Connection with Pending Merger with Carisma Therapeutics Schedules March 2, 2023, Special Meeting of Stockholders to Vote on Merger Launches www.SesenBioandCarisma.com, Pr

Filed by Sesen Bio, Inc. Pursuant to Rule 425 under the Securities Act of 1933 and deemed filed pursuant to Rule 14a-6(b) under the Securities Exchange Act of 1934 Subject Company: Sesen Bio, Inc. Commission File No.: 001-36296 Sesen Bio Files Definitive Proxy Statement and Mails Letter to Stockholders in Connection with Pending Merger with Carisma Therapeutics Schedules March 2, 2023, Special Mee

January 19, 2023 CORRESP

[Signature page follows]

January 19, 2023 CORRESPONDENCE FILED VIA EDGAR Office of Life Sciences Division of Corporation Finance U.

January 19, 2023 424B3

PROPOSED MERGER YOUR VOTE IS VERY IMPORTANT

TABLE OF CONTENTS  Filed Pursuant to Rule 424(b)(3)  Registration No. 333-267891 PROPOSED MERGER YOUR VOTE IS VERY IMPORTANT To the stockholders of Sesen Bio, Inc. and CARISMA Therapeutics Inc.: Sesen Bio, Inc., a Delaware corporation, or Sesen Bio, and CARISMA Therapeutics Inc., a Delaware corporation, or Carisma, entered into an Agreement and Plan of Merger and Reorganization on September 20, 20

January 19, 2023 425

Filed by Sesen Bio, Inc.

Filed by Sesen Bio, Inc. Pursuant to Rule 425 under the Securities Act of 1933 and deemed filed pursuant to Rule 14a-6(b) under the Securities Exchange Act of 1934 Subject Company: Sesen Bio, Inc. Commission File No.: 001-36296 On January 19, 2023, CARISMA Therapeutics Inc. published the following post on Twitter: NEW: Sesen Bio $SESN files definitive proxy statement and mails letter to stockholde

January 18, 2023 CORRESP

Hogan Lovells US LLP

CORRESP 1 filename1.htm Hogan Lovells US LLP 1735 Market Street, 23rd Floor Philadelphia, PA 19103 T +1 267 675 4500 F +1 267 675 4601 www.hoganlovells.com January 18, 2023 CORRESPONDENCE FILED VIA EDGAR Office of Life Sciences Division of Corporation Finance U.S. Securities and Exchange Commission 100 F Street, N.E. Washington, D.C. 20549 Attention: Ada D. Sarmento & Dillon Hagius Re: Sesen Bio,

January 18, 2023 EX-99.4

Consent of SVB Securities LLC, financial advisor to Sesen Bio, Inc.

EXHIBIT 99.4 CONSENT OF SVB SECURITIES LLC We hereby consent to the use of our opinion letter dated December 29, 2022 to the Board of Directors of Sesen Bio, Inc., included as Annex B to the proxy statement/prospectus which forms a part of Amendment No. 4 to the Registration Statement on Form S-4 of Sesen Bio, Inc. to be filed on the date hereof, and to the references to such opinion in such proxy

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