TCRX / TScan Therapeutics, Inc. - SEC-arkiveringar, Årsredovisning, Fullmaktsutlåtande

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 20, 2026 TSCAN THERAPEUTICS, I

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 20, 2026 TSCAN THERAPEUTICS, INC. (Exact name of registrant as specified in its charter) Delaware 001-40603 82-5282075 (State or other jurisdiction of incorporation) (Commission Fi

CERTIFICATE OF AMENDMENT TO THE AMENDED AND RESTATED CERTIFICATE OF INCORPORATION OF TSCAN THERAPEUTICS, INC

EX-3.1 Exhibit 3.1 CERTIFICATE OF AMENDMENT TO THE AMENDED AND RESTATED CERTIFICATE OF INCORPORATION OF TSCAN THERAPEUTICS, INC TScan Therapeutics, Inc. (the “Corporation”), a corporation duly organized and existing under the laws of the State of Delaware pursuant to Section 242 of the General Corporation Law of the State of Delaware (the “DGCL”), hereby certifies as follows: 1. The Amended and Re

FORM 8-K Item 2.02 Results of Operations and Financial Condition. On May 6, 2026, TScan Therapeutics, Inc. issued a press release announcing its financial results for the first quarter ended March 31, 2026. A copy of the press release is furnished as

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 6, 2026 TSCAN THERAPEUTICS, INC. (Exact name of registrant as specified in its charter) Delaware 001-40603 82-5282075 (State or other jurisdiction of incorporation) (Commission Fil

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

UNITED STATES SECURITIES AND EXCHANGE COMMISSION WASHINGTON, D.C. 20549 FORM 10-Q (Mark One) ☒ QUARTERLY REPORT PURSUANT TO SECTION 13 OR 15(d) OF THE SECURITIES EXCHANGE ACT OF 1934 For the quarterly period ended March 31, 2026 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: 001-40603 TSCAN THE

TScan Therapeutics Reports First Quarter 2026 Financial Results and Provides Corporate Update Early data on patients treated in Cohort C of the ALLOHA™ Phase 1 heme trial expected in the second quarter of 2026 Initiation of Phase 3 study of TSC-101 (

Exhibit 99.1 TScan Therapeutics Reports First Quarter 2026 Financial Results and Provides Corporate Update Early data on patients treated in Cohort C of the ALLOHA™ Phase 1 heme trial expected in the second quarter of 2026 Initiation of Phase 3 study of TSC-101 (ALLOHA-2™) planned for the second quarter of 2026 Initiation of Phase 1 study of TSC-102-A01 and TSC-102-A03 targeting CD45 in patients w

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2025 Annual Report UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.

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

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

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 31, 2026 TSCAN 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) March 31, 2026 TSCAN THERAPEUTICS, INC. (Exact name of registrant as specified in its charter) Delaware 001-40603 82-5282075 (State or other jurisdiction of incorporation) (Commission

As filed with the Securities and Exchange Commission on March 4, 2026

S-8 As filed with the Securities and Exchange Commission on March 4, 2026 Registration No.

FORM 8-K Item 2.02 Results of Operations and Financial Condition. On March 4, 2026, TScan Therapeutics, Inc. issued a press release announcing its financial results for the fourth quarter and fiscal year ended December 31, 2025. A copy of the press r

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 4, 2026 TSCAN THERAPEUTICS, INC. (Exact name of registrant as specified in its charter) Delaware 001-40603 82-5282075 (State or other jurisdiction of incorporation) (Commission F

Table 1: Newly Registered Securities

Calculation of Filing Fee Tables S-8 TScan Therapeutics, Inc. Table 1: Newly Registered Securities Security Type Security Class Title Fee Calculation Rule Amount Registered Proposed Maximum Offering Price Per Unit Maximum Aggregate Offering Price Fee Rate Amount of Registration Fee 1 Equity Common Stock, $0.0001 par value per share Other 5,196,535 $ 1.09 $ 5,664,223.15 0.0001381 $ 782.23 2 Equity

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) ☒ ANNUAL REPORT PURSUANT TO SECTION 13 OR 15(d) OF THE SECURITIES EXCHANGE ACT OF 1934 For the fiscal year ended December 31, 2025 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 001-406

Insider Trading Policy Introduction Persons and Transactions Covered by This Policy Material Non-Public Information Policies Regarding Material Non-Public Information Trading Blackout Periods Pre-Clearance of Trades Additional Restrictions and Guidan

Exhibit 19 Insider Trading Policy Table of Contents Page Introduction 1 A. Legal Prohibitions on Insider Trading 1 B. Detection and Prosecution of Insider Trading 1 C. Penalties for Violation of Insider Trading Laws and This Policy 2 D. Compliance Officer 2 E. Reporting Violations 3 F. Personal responsibility 3 Persons and Transactions Covered by This Policy 4 A. Persons Covered by This Policy 4 B

Jurisdiction of Incorporation or Organization

Exhibit 21 Subsidiaries Subsidiary Jurisdiction of Incorporation or Organization TScan Securities Corporation Massachusetts

TScan Therapeutics Reports Fourth Quarter and Full Year 2025 Financial Results and Provides Business Update Presented positive updated data from the ALLOHA™ Phase 1 heme trial at 67th American Society of Hematology (ASH) Annual Meeting and Exposition

Exhibit 99.1 TScan Therapeutics Reports Fourth Quarter and Full Year 2025 Financial Results and Provides Business Update Presented positive updated data from the ALLOHA™ Phase 1 heme trial at 67th American Society of Hematology (ASH) Annual Meeting and Exposition Announced completion of enrollment in Cohort C of Phase 1 ALLOHA™ trial; patients to be treated with commercial-ready manufacturing proc

Disclaimers and forward-looking statements This presentation and the accompanying discussion contain forward-looking statements within the meaning of the Private Securities Litigation Reform Act of 1995, including, but not limited to, express or impl

EX-99.1 Corporate Presentation January 2026 Exhibit 99.1 Disclaimers and forward-looking statements This presentation and the accompanying discussion contain forward-looking statements within the meaning of the Private Securities Litigation Reform Act of 1995, including, but not limited to, express or implied statements regarding the Company’s plans, progress, and timing relating to the Company’s

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 12, 2026 TSCAN 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): January 12, 2026 TSCAN THERAPEUTICS, INC. (Exact name of registrant as specified in its charter) Delaware 001-40603 82-5282075 (State or other jurisdiction of incorporation or organiz

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 25, 2025 TSCAN 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) November 25, 2025 TSCAN THERAPEUTICS, INC. (Exact name of registrant as specified in its charter) Delaware 001-40603 82-5282075 (State or other jurisdiction of incorporation) (Commissi

TScan Therapeutics Reports Third Quarter 2025 Financial Results and Provides Corporate Update Reached agreement with FDA on pivotal study design for TSC-101 following productive end of Phase 1 meeting Data from ALLOHA™ Phase 1 heme trial to be presen

Exhibit 99.1 TScan Therapeutics Reports Third Quarter 2025 Financial Results and Provides Corporate Update Reached agreement with FDA on pivotal study design for TSC-101 following productive end of Phase 1 meeting Data from ALLOHA™ Phase 1 heme trial to be presented at the 67th American Society of Hematology (ASH) Annual Meeting and Exposition Made the strategic decision to prioritize clinical dev

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

UNITED STATES SECURITIES AND EXCHANGE COMMISSION WASHINGTON, D.C. 20549 FORM 10-Q (Mark One) ☒ QUARTERLY REPORT PURSUANT TO SECTION 13 OR 15(d) OF THE SECURITIES EXCHANGE ACT OF 1934 For the quarterly period ended September 30, 2025 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: 001-40603 TSCAN

FORM 8-K Item 2.02 Results of Operations and Financial Condition. On November 12, 2025, TScan Therapeutics, Inc. issued a press release announcing its financial results for the third quarter September 30, 2025. A copy of the press release is furnishe

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 12, 2025 TSCAN THERAPEUTICS, INC. (Exact name of registrant as specified in its charter) Delaware 001-40603 82-5282075 (State or other jurisdiction of incorporation) (Commissi

TScan Therapeutics Reaches Agreement with FDA on Pivotal Study Design for TSC-101 and Announces Strategic Prioritization to Advance TSC-101 and Extend Cash Runway into H2 2027 Positive end of Phase I meeting and agreement reached with FDA on pivotal

EX-99.1 Exhibit 99.1 TScan Therapeutics Reaches Agreement with FDA on Pivotal Study Design for TSC-101 and Announces Strategic Prioritization to Advance TSC-101 and Extend Cash Runway into H2 2027 Positive end of Phase I meeting and agreement reached with FDA on pivotal study design for TSC-101 Dosed first solid tumor patients with multiplex TCR-T therapy; paused further enrollment to prioritize h

Disclaimers and forward-looking statements This presentation and accompanying discussion contain forward-looking statements within the meaning of the Private Securities Litigation Reform Act of 1995, including, but not limited to, express or implied

EX-99.2 Investor call November 3, 2025 Exhibit 99.2 Disclaimers and forward-looking statements This presentation and accompanying discussion contain forward-looking statements within the meaning of the Private Securities Litigation Reform Act of 1995, including, but not limited to, express or implied statements regarding the Company’s plans, progress, expectations, and timing relating to the Compa

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 3, 2025 TSCAN 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) November 3, 2025 TSCAN THERAPEUTICS, INC. (Exact name of registrant as specified in its charter) Delaware 001-40603 82-5282075 (State or other jurisdiction of incorporation) (Commissio

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 9, 2025 TSCAN 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) September 9, 2025 TSCAN THERAPEUTICS, INC. (Exact name of registrant as specified in its charter) Delaware 001-40603 82-5282075 (State or other jurisdiction of incorporation) (Commissi

Disclaimers and forward-looking statements This presentation and the accompanying discussion contain forward-looking TScan’s plans relating to developing and commercializing its TCR-T therapy statements within the meaning of the Private Securities Li

EX-99.1 Exhibit 99.1 Company Presentation September 2025 Disclaimers and forward-looking statements This presentation and the accompanying discussion contain forward-looking TScan’s plans relating to developing and commercializing its TCR-T therapy statements within the meaning of the Private Securities Litigation Reform Act of candidates, if approved, including sales strategy; estimates of the si

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 14, 2025 TSCAN 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) August 14, 2025 TSCAN THERAPEUTICS, INC. (Exact name of registrant as specified in its charter) Delaware 001-40603 82-5282075 (State or other jurisdiction of incorporation) (Commission

TScan Therapeutics Reports Second Quarter 2025 Financial Results and Provides Corporate Update Two-year relapse data from ALLOHA™ Phase 1 heme trial to be presented by end of year Expects to dose first solid tumor patients with multiplex TCR-T in the

Exhibit 99.1 TScan Therapeutics Reports Second Quarter 2025 Financial Results and Provides Corporate Update Two-year relapse data from ALLOHA™ Phase 1 heme trial to be presented by end of year Expects to dose first solid tumor patients with multiplex TCR-T in the third quarter of 2025 Cash, cash equivalents, and marketable securities continue to fund operations into the first quarter of 2027 WALTH

FORM 8-K Item 2.02 Results of Operations and Financial Condition. On August 12, 2025, TScan Therapeutics, Inc. issued a press release announcing its financial results for the second quarter June 30, 2025. A copy of the press release is furnished as 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) August 12, 2025 TSCAN THERAPEUTICS, INC. (Exact name of registrant as specified in its charter) Delaware 001-40603 82-5282075 (State or other jurisdiction of incorporation) (Commission

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

UNITED STATES SECURITIES AND EXCHANGE COMMISSION WASHINGTON, D.C. 20549 FORM 10-Q (Mark One) ☒ 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 ☐ 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: 001-40603 TSCAN THER

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 30, 2025 TSCAN 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 30, 2025 TSCAN THERAPEUTICS, INC. (Exact name of registrant as specified in its charter) Delaware 001-40603 82-5282075 (State or other jurisdiction of incorporation) (Commission F

UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 SCHEDULE 14A INFORMATION 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 INFORMATION 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 permit

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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, 2024 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 001-40603 TScan Therapeut

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  ☒ 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)) ☐ Def

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

UNITED STATES SECURITIES AND EXCHANGE COMMISSION WASHINGTON, D.C. 20549 FORM 10-Q (Mark One) ☒ 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 ☐ 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: 001-40603 TSCAN THE

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) May 6, 2025 TSCAN THERAPEUTICS, INC. (Exact name of registrant as specified in its charter) Delaware 001-40603 82-5282075 (State or other jurisdiction of incorporation) (Commission Fil

TScan Therapeutics Reports First Quarter 2025 Financial Results and Provides Corporate Update Updates from the PLEXI-T™ solid tumor and ALLOHA™ heme Phase 1 clinical trials anticipated by end of year On-track to file IND application for TSC-102-A0301

Exhibit 99.1 TScan Therapeutics Reports First Quarter 2025 Financial Results and Provides Corporate Update Updates from the PLEXI-T™ solid tumor and ALLOHA™ heme Phase 1 clinical trials anticipated by end of year On-track to file IND application for TSC-102-A0301 (CD45; HLA-A*03:01) to FDA in the second half of the year Appointed commercial leader Stephen Camiolo as Senior Vice President, Market A

TScan Therapeutics, Inc. 830 Winter Street Waltham, Massachusetts 02451

TScan Therapeutics, Inc. 830 Winter Street Waltham, Massachusetts 02451 March 12, 2025 Via EDGAR Transmission U.S. Securities and Exchange Commission Division of Corporation Finance 100 F Street, N.E. Washington, D.C. 20549 Re: TScan Therapeutics, Inc. Acceleration Request for Registration Statement on Form S-3 (File No. 333-285570) Ladies and Gentlemen: Pursuant to Rule 461 under the Securities A

LETTER

March 11, 2025 Gavin MacBeath Chief Executive Officer TScan Therapeutics, Inc. 830 Winter Street Waltham, MA 02451 Re: TScan Therapeutics, Inc. Registration Statement on Form S-3 Filed March 5, 2025 File No. 333-285570 Dear Gavin MacBeath: This is to advise you that we have not reviewed and will not review your registration statement. Please refer to Rules 460 and 461 regarding requests for accele

TScan Therapeutics Reports Fourth Quarter and Full Year 2024 Financial Results and Provides Business Update Presented updated data from ongoing ALLOHA™ Phase 1 heme trial at the 66th ASH Annual Meeting and Exposition IND application cleared for seven

Exhibit 99.1 TScan Therapeutics Reports Fourth Quarter and Full Year 2024 Financial Results and Provides Business Update Presented updated data from ongoing ALLOHA™ Phase 1 heme trial at the 66th ASH Annual Meeting and Exposition IND application cleared for seventh TCR in PLEXI-T™ Phase 1 solid tumor program; TSC-202-A0201 targeting MAGE-A4 on HLA-A*02:01 Closed $30 million registered direct offer

Insider Trader Policy.

Exhibit 19 Insider Trading Policy Table of Contents Page Introduction 1 A. Legal Prohibitions on Insider Trading 1 B. Detection and Prosecution of Insider Trading 1 C. Penalties for Violation of Insider Trading Laws and This Policy 2 D. Compliance Officer 2 E. Reporting Violations 3 F. Personal responsibility 3 Persons and Transactions Covered by This Policy 4 A. Persons Covered by This Policy 4 B

Filing Fee Table.

Exhibit 107.1 Calculation of Filing Fee Tables Form S-8 (Form Type) TScan Therapeutics, Inc. (Exact Name of Registrant as Specified in its Charter) Table 1: Newly Registered Securities Security Type Security Class Title Fee Calculation Rule Amount Registered(1) Proposed Maximum Offering Price per Share Maximum Aggregate Offering Price Fee Rate Amount of Registration Fee Equity Common Stock, $0.000

List of Subsidiaries of Registrant.

Exhibit 21 Subsidiaries Subsidiary Jurisdiction of Incorporation or Organization TScan Securities Corporation Massachusetts

Power of Attorney (included on signature page).

As filed with the Securities and Exchange Commission on March 5, 2025 Registration No.

Form of Senior Indenture between Registrant and one or more trustees to be named.

EX-4.3 Exhibit 4.3 TSCAN THERAPEUTICS, INC. Issuer AND [TRUSTEE], Trustee INDENTURE Dated as of [•], 202[•] Senior Debt Securities TABLE OF CONTENTS1 Page Article 1 DEFINITIONS 1 Section 1.01 Definitions of Terms 1 Article 2 ISSUE, DESCRIPTION, TERMS, EXECUTION, REGISTRATION AND EXCHANGE OF SECURITIES 4 Section 2.01 Designation and Terms of Securities 4 Section 2.02 Form of Securities and Trustee’

Form of Subordinated Indenture between Registrant and one or more trustees to be named.

Exhibit 4.4 TSCAN THERAPEUTICS, INC. Issuer AND [TRUSTEE], Trustee INDENTURE Dated as of [•], 202[•] Subordinated Debt Securities TABLE OF CONTENTS(1) Article 1 DEFINITIONS 1 Section 1.01 Definitions of Terms 1 Article 2 ISSUE, DESCRIPTION, TERMS, EXECUTION, REGISTRATION AND EXCHANGE OF SECURITIES 4 Section 2.01 Designation and Terms of Securities 4 Section 2.02 Form of Securities and Trustee’s Ce

As filed with the Securities and Exchange Commission on March 5, 2025

S-3 As filed with the Securities and Exchange Commission on March 5, 2025 Registration No.

Filing Fee Table

EX-FILING FEES Exhibit 107 CALCULATION OF REGISTRATION FEE TScan Therapeutics, Inc.

Form 10-K

Table of Contents 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, 2024 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 001-406

Second Amendment to Lease by and between PPF OFF 828-830 Winter Street LLC and the Registrant, dated October 28, 2024.

Exhibit 10.9 830 WINTER STREET WALTHAM, MASSACHUSETTS (the “Building”) SECOND AMENDMENT (“Second Amendment”) EXECUTION DATE: October 28, 2024 (the “Execution Date”) LANDLORD: PPF OFF 828-830 Winter Street LLC, a Delaware limited liability company TENANT: TScan Therapeutics, Inc., a Delaware corporation EXISTING PREMISES: Approximately 25,472 rentable square feet of space in the Building, consistin

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) March 5, 2025 TSCAN THERAPEUTICS, INC. (Exact name of registrant as specified in its charter) Delaware 001-40603 82-5282075 (State or other jurisdiction of incorporation) (Commission F

JOINT FILING AGREEMENT

EX-1 2 jfa.htm EXHIBIT 1 JOINT FILING AGREEMENT The undersigned hereby agree that the statement on Schedule 13G with respect to the Voting Common Stock of TScan Therapeutics, Inc., dated as of February 14, 2025, is, and any amendments thereto (including amendments on Schedule 13D) signed by each of the undersigned shall be, filed on behalf of each of us pursuant to and in accordance with the provi

Form of Pre-Funded Warrant.

Exhibit 4.1 TSCAN THERAPEUTICS, INC. FORM OF PRE-FUNDED WARRANT TO PURCHASE COMMON STOCK Number of Shares: [*] (subject to adjustment) Warrant No.[*] Original Issue Date: December [*], 2024 TScan Therapeutics, Inc., a Delaware corporation (the “Company”), hereby certifies that, for good and valuable consideration, the receipt and sufficiency of which are hereby acknowledged, [*] or its registered

Form of Securities Purchase Agreement.

Exhibit 10.1 SECURITIES PURCHASE AGREEMENT This Securities Purchase Agreement (this “Agreement”) is dated as of December 26, 2024, by and TScan Therapeutics, Inc., a Delaware corporation (the “Company”), and the purchasers identified on the signature pages hereto (each, including its successors and assigns, a “Purchaser”). RECITALS WHEREAS, subject to the terms and conditions set forth in this Agr

Pre-Funded Warrants to Purchase 7,500,000 Shares of Common Stock

424B5 Table of Contents Filed Pursuant to Rule 424(b)(5) Registration No. 333-268260 PROSPECTUS SUPPLEMENT (To Prospectus Dated May 16, 2023) Pre-Funded Warrants to Purchase 7,500,000 Shares of Common Stock We are offering pre-funded warrants to purchase 7,500,000 shares of voting common stock, in a registered direct offering to a limited number of institutional investors purchaser pursuant to thi

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) December 26, 2024 TSCAN THERAPEUTICS, INC. (Exact name of registrant as specified in its charter) Delaware 001-40603 82-5282075 (State or other jurisdiction of incorporation) (Commissi

TScan Therapeutics Refinances Existing Convertible Debt Facility with Term Loan for up to $52.5 Million from Silicon Valley Bank New non-dilutive structure replaces existing convertible facility maturing in 2026, and extends loan maturity to 2029

Exhibit 99.1 TScan Therapeutics Refinances Existing Convertible Debt Facility with Term Loan for up to $52.5 Million from Silicon Valley Bank New non-dilutive structure replaces existing convertible facility maturing in 2026, and extends loan maturity to 2029 WALTHAM, Mass., December 23, 2024 — TScan Therapeutics, Inc. (Nasdaq: TCRX), a clinical-stage biotechnology company focused on the developme

Loan and Security Agreement, dated December 20, 2024, by and among TScan Therapeutics, Inc. and Silicon Valley Bank, a division of First-Citizens Bank & Trust Company†

Exhibit 10.1 [Certain portions of this exhibit have been excluded because they are not material and are the type that the registrant treats as private or confidential.] LOAN AND SECURITY AGREEMENT THIS LOAN AND SECURITY AGREEMENT (this “Agreement”) is dated as of the Effective Date between SILICON VALLEY BANK, A DIVISION OF FIRST-CITIZENS BANK & TRUST COMPANY (“Bank”) and TSCAN THERAPEUTICS, INC.,

Entry into a Material Definitive Agreement, Termination of a Material Definitive Agreement, Creation of a Direct Financial Obligation or an Obligation under an Off-Balance Sheet Arrangement of a Registrant

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 20, 2024 TSCAN THERAPEUTICS, INC. (Exact name of registrant as specified in its charter) Delaware 001-40603 82-5282075 (State or other jurisdiction of incorporation or organi

TScan Therapeutics to Present Updated Data from the Ongoing ALLOHA™ Phase 1 Heme Trial During Oral Session at the 66th American Society of Hematology Annual Meeting and Exposition To date, event-free survival strongly favors the treatment arm (HR=0.3

Exhibit 99.1 TScan Therapeutics to Present Updated Data from the Ongoing ALLOHA™ Phase 1 Heme Trial During Oral Session at the 66th American Society of Hematology Annual Meeting and Exposition To date, event-free survival strongly favors the treatment arm (HR=0.30; p=0.04), and treatment-arm patients trend towards lower probability of relapse (HR=0.28; p=0.14) No dose-limiting toxicities observed

Disclaimers and forward-looking statements This presentation and the accompanying discussion contain forward-looking statements within the meaning of the Private Securities Litigation Reform Act of 1995, including, but not limited to, express or impl

KOL Event December 10, 2024 Exhibit 99.2 Disclaimers and forward-looking statements This presentation and the accompanying discussion contain forward-looking statements within the meaning of the Private Securities Litigation Reform Act of 1995, including, but not limited to, express or implied statements regarding Tscan Therapeutics, Inc. (the “Company” or “TScan”)’s plans, progress, and timing re

Regulation FD Disclosure

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 9, 2024 TSCAN THERAPEUTICS, INC. (Exact name of registrant as specified in its charter) Delaware 001-40603 82-5282075 (State or other jurisdiction of incorporation) (Commissio

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 15, 2024

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 15, 2024 TSCAN THERAPEUTICS, INC. (Exact name of registrant as specified in its charter) Delaware 001-40603 82-5282075 (State or other jurisdiction of incorporation or organi

TCRX / TScan Therapeutics, Inc. / Cormorant Asset Management, LP Passive Investment

UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, DC 20549 SCHEDULE 13G/A Under the Securities Exchange Act of 1934 (Amendment No.

TCRX / TScan Therapeutics, Inc. / BIOTECHNOLOGY VALUE FUND L P - AMENDMENT NO. 1 TO SCHEDULE 13G Passive Investment

SC 13G/A 1 sc13ga107422tcrx11142024.htm AMENDMENT NO. 1 TO SCHEDULE 13G UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 SCHEDULE 13G (Rule 13d-102) INFORMATION TO BE INCLUDED IN STATEMENTS FILED PURSUANT TO RULES 13d-1(b), (c), AND (d) AND AMENDMENTS THERETO FILED PURSUANT TO RULE 13d-2(b) (Amendment No. 1)1 TScan Therapeutics, Inc. (Name of Issuer) Voting Common Stock, $0.

TCRX / TScan Therapeutics, Inc. / K2 HealthVentures Equity Trust LLC - SC 13G/A Passive Investment

UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 SCHEDULE 13G Under the Securities Exchange Act of 1934 (Amendment No. 2)* TScan Therapeutics, Inc. (Name of Issuer) Voting Common Stock, $0.0001 par value per share (Title of Class of Securities) 89854M101 (CUSIP Number) September 30, 2024 (Date of Event Which Requires Filing of this Statement) Check the appropriate box to des

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

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 12, 2024 TSCAN THERAPEUTICS, INC. (Exact name of registrant as specified in its charter) Delaware 001-40603 82-5282075 (State or other jurisdiction of incorporation) (Commissi

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

UNITED STATES SECURITIES AND EXCHANGE COMMISSION WASHINGTON, D.C. 20549 FORM 10-Q (Mark One) ☒ 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 ☐ 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: 001-40603 TSCAN

TScan Therapeutics Reports Third Quarter 2024 Financial Results and Provides Corporate Update Upcoming oral presentation for the ALLOHATM Phase 1 heme trial at the 66th American Society of Hematology (ASH) Annual Meeting and Exposition Company to hos

Exhibit 99.1 TScan Therapeutics Reports Third Quarter 2024 Financial Results and Provides Corporate Update Upcoming oral presentation for the ALLOHATM Phase 1 heme trial at the 66th American Society of Hematology (ASH) Annual Meeting and Exposition Company to host virtual KOL event featuring Ran Reshef, M.D., M.Sc., on Tuesday, December 10th at 8:00 a.m. ET to discuss clinical updates from the ALL

TCRX / TScan Therapeutics, Inc. / BlackRock, Inc. Passive Investment

SC 13G 1 us89854m1018110824.txt us89854m1018110824.txt SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 SCHEDULE 13G Under the Securities Exchange Act of 1934 (Amendment No: ) TScan Therapeutics, Inc. - (Name of Issuer) Common Stock - (Title of Class of Securities) 89854M101 - (CUSIP Number) September 30, 2024 - (Date of Event Which Requires Filing of this Statement) Check the appropriate

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 28, 2024 TSCAN 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) October 28, 2024 TSCAN THERAPEUTICS, INC. (Exact name of registrant as specified in its charter) Delaware 001-40603 82-5282075 (State or other jurisdiction of incorporation) (Commissio

TCRX / TScan Therapeutics, Inc. / BlackRock, Inc. Passive Investment

us89854m1018102124.txt SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 SCHEDULE 13G Under the Securities Exchange Act of 1934 (Amendment No: ) TScan Therapeutics, Inc. - (Name of Issuer) Common Stock - (Title of Class of Securities) 89854M101 - (CUSIP Number) September 30, 2024 - (Date of Event Which Requires Filing of this Statement) Check the appropriate box to designate the rule pursu

TScan Therapeutics Reports Second Quarter 2024 Financial Results and Provides Corporate Update FDA grants RMAT designation to TSC-100 and TSC-101 for the treatment of patients with AML, ALL, and MDS undergoing allogeneic HCT with reduced intensity co

Exhibit 99.1 TScan Therapeutics Reports Second Quarter 2024 Financial Results and Provides Corporate Update FDA grants RMAT designation to TSC-100 and TSC-101 for the treatment of patients with AML, ALL, and MDS undergoing allogeneic HCT with reduced intensity conditioning Engaged CDMO with global capabilities to support manufacturing for pivotal trials and commercialization On-track to report ini

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

UNITED STATES SECURITIES AND EXCHANGE COMMISSION WASHINGTON, D.C. 20549 FORM 10-Q (Mark One) ☒ 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 ☐ 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: 001-40603 TSCAN THER

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) August 12, 2024 TSCAN THERAPEUTICS, INC. (Exact name of registrant as specified in its charter) Delaware 001-40603 82-5282075 (State or other jurisdiction of incorporation) (Commission

Employment Agreement, dated April 4, 2024 by and between Registrant and Chrystal Louis.

Exhibit 10.1 Employment Agreement THIS AGREEMENT (the “Agreement”) is entered into by and between Chrystal Louis (the “Executive” or “you”) and TScan Therapeutics, Inc. (the “Company”), a Delaware corporation, as of the date all parties hereto have signed the Agreement. 1. Duties and Scope of Employment. (a) Position. The Company agrees to employ the Executive in the position of Chief Medical Offi

As filed with the Securities and Exchange Commission on June 14, 2024

As filed with the Securities and Exchange Commission on June 14, 2024 Registration No.

Filing Fee Table.

Exhibit 107.1 Calculation of Filing Fee Tables Form S-8 (Form Type) TScan Therapeutics, Inc. (Exact Name of Registrant as Specified in its Charter) Table 1: Newly Registered Securities Security Type Security Class Title Fee Calculation Rule Amount Registered(1) Proposed Maximum Offering Price per Share Maximum Aggregate Offering Price Fee Rate Amount of Registration Fee Equity Common Stock, $0.000

TScan Therapeutics Announces Updates to its Board of Directors Garry A. Nicholson, an experienced executive with regulatory and commercial expertise, joins the Board of Directors Timothy Barberich retires as Chair; Stephen Biggar, M.D., Ph.D. assumes

EX-99.1 Exhibit 99.1 TScan Therapeutics Announces Updates to its Board of Directors Garry A. Nicholson, an experienced executive with regulatory and commercial expertise, joins the Board of Directors Timothy Barberich retires as Chair; Stephen Biggar, M.D., Ph.D. assumes the role of Chair WALTHAM, Mass., June 14, 2024 — TScan Therapeutics, Inc. (Nasdaq: TCRX), a clinical-stage biopharmaceutical co

Amended and Restated TScan Therapeutic, Inc. 2021 Equity Incentive Plan

EX-10.1 Exhibit 10.1 TSCAN THERAPEUTICS, INC. AMENDED AND RESTATED 2021 EQUITY INCENTIVE PLAN Adopted on April 22, 2021 Amended and Restated on June 12, 2024 TSCAN THERAPEUTICS, INC. AMENDED AND RESTATED 2021 EQUITY INCENTIVE PLAN ARTICLE 1. INTRODUCTION. The Board adopted the Plan to become effective immediately, although no Awards may be granted prior to the IPO Date. The purpose of the Plan is

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 12, 2024 TSCAN 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 12, 2024 TSCAN THERAPEUTICS, INC. (Exact name of registrant as specified in its charter) Delaware 001-40603 82-5282075 (State or other jurisdiction of incorporation) (Commission F

Employment Agreement, dated January 29, 2024, by and between the Registrant and Jason A. Amello.

Exhibit 10.1 Employment Agreement This Agreement (the “Agreement”) is entered into by and between Jason A. Amello (the “Executive” or “you”) and TScan Therapeutics, Inc. (the “Company”), a Delaware corporation, as of the date all parties hereto have signed the Agreement. 1. Duties and Scope of Employment. (a) Position. The Company agrees to employ the Executive in the position of Chief Financial O

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

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 13, 2024 TSCAN THERAPEUTICS, INC. (Exact name of registrant as specified in its charter) Delaware 001-40603 82-5282075 (State or other jurisdiction of incorporation) (Commission Fi

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

UNITED STATES SECURITIES AND EXCHANGE COMMISSION WASHINGTON, D.C. 20549 FORM 10-Q (Mark One) ☒ 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 ☐ 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: 001-40603 TSCAN THE

TScan Therapeutics Reports First Quarter 2024 Financial Results and Provides Corporate Update First patient dosed in Phase 1 clinical trial for the treatment of solid tumors; initial data anticipated in 2024 All treatment-arm patients in the Phase 1

Exhibit 99.1 TScan Therapeutics Reports First Quarter 2024 Financial Results and Provides Corporate Update First patient dosed in Phase 1 clinical trial for the treatment of solid tumors; initial data anticipated in 2024 All treatment-arm patients in the Phase 1 heme program remain relapse-free with no detectable disease, with a median follow-up of >10 months Closed upsized underwritten public off

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  ☒ 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)) ☐ Def

ARS

UNITEDSTATES SECURITIESANDEXCHANGECOMMISSION Washington,D.C.20549 FORM10-K (MarkOne)  ANNUALREPORTPURSUANTTOSECTION13OR15(d)OFTHESECURITIESEXCHANGEACTOF1934 ForthefiscalyearendedDecember31,2023 OR  TRANSITIONREPORTPURSUANTTOSECTION13OR15(d)OFTHESECURITIESEXCHANGEACTOF1934FORTHE TRANSITIONPERIODFROM TO CommissionFileNumber001-40603 TScanTherapeutics,Inc. (ExactnameofRegistrantasspecifiedinitsChar

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

JOINT FILING AGREEMENT

EX-99.1 2 exhibit99-1.htm Exhibit 99.1 JOINT FILING AGREEMENT This Joint Filing Agreement, dated as of April 29, 2024, is by and among Cormorant Global Healthcare Master Fund, LP, Cormorant Global Healthcare GP, LLC, Cormorant Asset Management, LP and Bihua Chen (collectively, the “Filers”). Each of the Filers may be required to file with the United States Securities and Exchange Commission a stat

TCRX / TScan Therapeutics, Inc. / Cormorant Asset Management, LP Passive Investment

SC 13G 1 sc13g.htm UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 SCHEDULE 13G Under the Securities Exchange Act of 1934 (Amendment No. )* TScan Therapeutics, Inc. (Name of Issuer) Voting Common Stock (Title of Class of Securities) 89854M101 (CUSIP Number) April 19, 2024 (Date of Event which Requires Filing of this Statement) Check the appropriate box to designate the rule

TCRX / TScan Therapeutics, Inc. / BAKER BROS. ADVISORS LP - SC 13D/A Activist Investment

SC 13D/A 1 tm2412362d1sc13da.htm SC 13D/A UNITED STATES SECURITIES AND EXCHANGE COMMISSION WASHINGTON, DC 20549 SCHEDULE 13D (Rule 13d-102) INFORMATION TO BE INCLUDED IN STATEMENTS FILED PURSUANT TO RULE 13d-l(a) AND AMENDMENTS THERETO FILED PURSUANT TO RULE 13d-2(a) (Amendment No. 3)* TScan Therapeutics, Inc. (Name of Issuer) Common Stock, par value $0.0001 per share (Title of Class of Securities

2,472,581 Shares of Common Stock Pre-Funded Warrants to Purchase 18,577,419 Shares of Common Stock

424B5 Table of Contents Filed Pursuant to Rule 424(b)(5) Registration No. 333-277699 PROSPECTUS SUPPLEMENT (To Prospectus Dated April 12, 2024) 2,472,581 Shares of Common Stock Pre-Funded Warrants to Purchase 18,577,419 Shares of Common Stock We are offering 2,472,581 shares of our voting common stock and, in lieu of voting common stock to certain investors that so choose, pre-funded warrants to p

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 16, 2024 TSCAN 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) April 16, 2024 TSCAN THERAPEUTICS, INC. (Exact name of registrant as specified in its charter) Delaware 001-40603 82-5282075 (State or other jurisdiction of incorporation) (Commission

Form of Director Lock-Up Agreement (incorporated by reference to Exhibit A to Exhibit 1.1 to the Issuer’s Current Report on Form 8-K, filed with the SEC on April 17, 2024).

Exhibit 1.1 Execution Version 2,472,581 SHARES OF COMMON STOCK (PAR VALUE $0.0001 PER SHARE) PRE-FUNDED WARRANTS TO PURCHASE 18,577,419 SHARES OF COMMON STOCK TScan Therapeutics, Inc. UNDERWRITING AGREEMENT April 16, 2024 April 16, 2024 Morgan Stanley & Co. LLC TD Securities (USA) LLC as Representatives of the several Underwriters listed in Schedule II hereto c/o Morgan Stanley & Co. LLC 1585 Broa

Form of Pre-Funded Warrant.

Exhibit 4.1 TSCAN THERAPEUTICS, INC. FORM OF PRE-FUNDED WARRANT TO PURCHASE COMMON STOCK Number of Shares: [*] (subject to adjustment) Warrant No.[*] Original Issue Date: April [*], 2024 TScan Therapeutics, Inc., a Delaware corporation (the “Company”), hereby certifies that, for good and valuable consideration, the receipt and sufficiency of which are hereby acknowledged, [*] or its registered ass

TScan Therapeutics Announces Launch of $125 million Proposed Public Offering

Exhibit 99.1 TScan Therapeutics Announces Launch of $125 million Proposed Public Offering WALTHAM, Mass., April 16, 2024 (GLOBE NEWSWIRE) — TScan Therapeutics, Inc. (Nasdaq: TCRX), a clinical-stage biopharmaceutical company focused on the development of T cell receptor (TCR)-engineered T cell therapies (TCR-T) for the treatment of patients with cancer, today announced that it has commenced an unde

TScan Therapeutics, Inc.

Free Writing Prospectus Filed Pursuant to Rule 433 To Prospectus dated April 12, 2024 Preliminary Prospectus Supplement dated April 16, 2024 Registration Statement File No.

TScan Therapeutics Announces Pricing of Upsized $150 Million Public Offering

Exhibit 99.2 TScan Therapeutics Announces Pricing of Upsized $150 Million Public Offering WALTHAM, Mass., April 17, 2024 (GLOBE NEWSWIRE) — TScan Therapeutics, Inc. (Nasdaq: TCRX), a clinical-stage biopharmaceutical company focused on the development of T cell receptor (TCR)-engineered T cell therapies (TCR-T) for the treatment of patients with cancer, today announced the pricing of an underwritte

TScan Therapeutics Provides Clinical Pipeline Update and Highlights Near-Term Priorities Over 40 solid tumor patients have completed all biomarker testing in the screening protocol; ~60% of these patients qualify for at least one TCR-T in the ImmunoB

EX-99.1 Exhibit 99.1 TScan Therapeutics Provides Clinical Pipeline Update and Highlights Near-Term Priorities Over 40 solid tumor patients have completed all biomarker testing in the screening protocol; ~60% of these patients qualify for at least one TCR-T in the ImmunoBank and ~30% are eligible for multiplex therapy Patients identified across all six TCR-T cohorts in solid tumor program with dosi

$125,000,000 Shares of Common Stock Pre-Funded Warrants to Purchase    Shares of Common Stock

Table of Contents Filed Pursuant to Rule 424(b)(5) Registration No. 333-277699 This preliminary prospectus supplement and the accompanying prospectus relate to an effective registration statement under the Securities Act of 1933, as amended, but the information in this prospectus supplement is not complete and may be changed. This preliminary prospectus supplement and the accompanying prospectus a

Disclaimers and forward-looking statements This presentation and the accompanying discussion contain forward-looking TScan’s plans relating to developing and commercializing its TCR-T therapy statements within the meaning of the Private Securities Li

EX-99.2 Exhibit 99.2 TScan Therapeutics April 2024 Disclaimers and forward-looking statements This presentation and the accompanying discussion contain forward-looking TScan’s plans relating to developing and commercializing its TCR-T therapy statements within the meaning of the Private Securities Litigation Reform Act of candidates, if approved, including sales strategy; estimates of the size of

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 16, 2024 TSCAN 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) April 16, 2024 TSCAN THERAPEUTICS, INC. (Exact name of registrant as specified in its charter) Delaware 001-40603 82-5282075 (State or other jurisdiction of incorporation) (Commission

TScan Therapeutics, Inc. 830 Winter Street Waltham, Massachusetts 02451

TScan Therapeutics, Inc. 830 Winter Street Waltham, Massachusetts 02451 April 10, 2024 Via EDGAR Transmission U.S. Securities and Exchange Commission Division of Corporation Finance 100 F Street, N.E. Washington, D.C. 20549 Re: TScan Therapeutics, Inc. Acceleration Request for Registration Statement on Form S-3 (File No. 333-277699) Ladies and Gentlemen: Pursuant to Rule 461 under the Securities A

UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 FORM 10-K/A (Amendment No. 1) (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, 2023 OR ☐ T

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

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 8, 2024 TSCAN 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) April 8, 2024 TSCAN THERAPEUTICS, INC. (Exact name of registrant as specified in its charter) Delaware 001-40603 82-5282075 (State or other jurisdiction of incorporation) (Commission F

TScan Therapeutics Appoints Seasoned Hematology and Oncology Expert Chrystal U. Louis, M.D., M.P.H., as Chief Medical Officer Dr. Louis brings to TScan extensive experience in cell therapy, medical affairs, and clinical and commercial development

Exhibit 99.1 TScan Therapeutics Appoints Seasoned Hematology and Oncology Expert Chrystal U. Louis, M.D., M.P.H., as Chief Medical Officer Dr. Louis brings to TScan extensive experience in cell therapy, medical affairs, and clinical and commercial development WALTHAM, Mass., April 8, 2024 — TScan Therapeutics, Inc. (Nasdaq: TCRX), a clinical-stage biopharmaceutical company focused on the developme

LETTER

United States securities and exchange commission logo March 7, 2024 Zoran Zdraveski Chief Legal and Strategy Officer TScan Therapeutics, Inc.

Filing Fee Table

Exhibit 107 CALCULATION OF REGISTRATION FEE TScan Therapeutics, Inc. (Exact name of Registrant as Specified in its Charter) Table 1: Newly Registered and Carry Forward Securities (Form S-3) Security Type Security Class Title Fee Calculation or Carry Forward Rule Amount Registered Proposed Maximum Offering Price Per Unit (2) Maximum Aggregate Offering Price Fee Rate Amount of Registration Fee Carry

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

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, 2024 TSCAN THERAPEUTICS, INC. (Exact name of registrant as specified in its charter) Delaware 001-40603 82-5282075 (State or other jurisdiction of incorporation) (Commission F

Form of Senior Indenture between Registrant and one or more trustees to be named.

Exhibit 4.4 TSCAN THERAPEUTICS, INC. Issuer AND [TRUSTEE], Trustee INDENTURE Dated as of [•], 202[•] Senior Debt Securities TABLE OF CONTENTS1 Page Article 1 DEFINITIONS 1 Section 1.01 Definitions of Terms 1 Article 2 ISSUE, DESCRIPTION, TERMS, EXECUTION, REGISTRATION AND EXCHANGE OF SECURITIES 4 Section 2.01 Designation and Terms of Securities 4 Section 2.02 Form of Securities and Trustee’s Certi

Power of Attorney (included on signature page).

S-8 As filed with the Securities and Exchange Commission on March 6, 2024 Registration No.

Employment Agreement, dated July 28, 2021, by and between the Registrant and Zoran Zdraveski.

Exhibit 10.17 EMPLOYMENT AGREEMENT THIS AGREEMENT (the “Agreement”) is entered into by and between ZORAN ZDRAVESKI (the “Executive” or “you”) and TSCAN THERAPEUTICS, INC., a Delaware corporation (the “Company”), as of the date all parties hereto have signed the Agreement. 1. Duties and Scope of Employment. (a) Position. For the term of his employment under this Agreement (the “Employment”), the Co

Employment Agreement, dated May 25, 2023, by and between the Registrant and Gavin MacBeath, Ph.D.

Exhibit 10.14 Employment Agreement This Agreement (the “Agreement”), effective as of May 25, 2023, is entered into by and between GAVIN MACBEATH (the “Executive” or “you”) and TScan Therapeutics, Inc. (the “Company”), a Delaware corporation and replaces and supersedes all other employment agreements and understandings between the Executive and Company except as otherwise set forth herein. 1. Dutie

Form of Subordinated Indenture between Registrant and one or more trustees to be named.

Exhibit 4.5 TSCAN THERAPEUTICS, INC. Issuer AND [TRUSTEE], Trustee INDENTURE Dated as of [•], 202[•] Subordinated Debt Securities TABLE OF CONTENTS(1) Article 1 DEFINITIONS 1 Section 1.01 Definitions of Terms 1 Article 2 ISSUE, DESCRIPTION, TERMS, EXECUTION, REGISTRATION AND EXCHANGE OF SECURITIES 4 Section 2.01 Designation and Terms of Securities 4 Section 2.02 Form of Securities and Trustee’s Ce

List of Subsidiaries of Registrant.

Exhibit 21 Subsidiaries Subsidiary Jurisdiction of Incorporation or Organization TScan Securities Corporation Massachusetts

Form 10-K

Table of Contents 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, 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 001-406

Compensation Recovery Policy.

Exhibit 97 TSCan therapeutics, Inc. COMPENSATION RECOVERY POLICY Adopted as of September 21, 2023 TScan Therapeutics, Inc., a Delaware corporation (the “Company”), has adopted a Compensation Recovery Policy (this “Policy”) as described below. 1. Overview The Policy sets forth the circumstances and procedures under which the Company shall recover Erroneously Awarded Compensation from Covered Person

TScan Therapeutics Reports Fourth Quarter and Full Year 2023 Financial Results and Provides Business Update Presented updated data from ongoing Phase 1 study of TSC-100 and TSC-101 for the treatment of heme malignancies at the Tandem Meetings of ASTC

Exhibit 99.1 TScan Therapeutics Reports Fourth Quarter and Full Year 2023 Financial Results and Provides Business Update Presented updated data from ongoing Phase 1 study of TSC-100 and TSC-101 for the treatment of heme malignancies at the Tandem Meetings of ASTCT and CIBMTR; 8/8 (100%) patients in treatment arms are relapse-free and show complete donor chimerism Announced the clearance of two add

Filing Fee Table.

Exhibit 107.1 Calculation of Filing Fee Tables Form S-8 (Form Type) TScan Therapeutics, Inc. (Exact Name of Registrant as Specified in its Charter) Table 1: Newly Registered Securities Security Type Security Class Title Fee Calculation Rule Amount Registered(1) Proposed Maximum Offering Price per Share Maximum Aggregate Offering Price Fee Rate Amount of Registration Fee Equity Common Stock, $0.000

As filed with the Securities and Exchange Commission on March 6, 2024

Table of Contents As filed with the Securities and Exchange Commission on March 6, 2024 Registration No.

TCRX / TScan Therapeutics, Inc. / K2 HealthVentures Equity Trust LLC - SC 13G/A Passive Investment

SC 13G/A 1 ef20021589sc13ga.htm 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)* TScan Therapeutics, Inc. (Name of Issuer) Voting Common Stock, $0.0001 par value per share (Title of Class of Securities) 89854M101 (CUSIP Number) December 31, 2023 (Date of Event Which Requires Filing of this Sta

TCRX / TScan Therapeutics, Inc. / GV 2017, L.P. - SC 13G/A Passive Investment

UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 Schedule 13G Under the Securities Exchange Act of 1934 (Amendment No. 1)* TScan Therapeutics, Inc. (Name of Issuer) Voting Common Stock, par value $0.0001 per share (Title of Class of Securities) 89854M101 (CUSIP Number) December 31, 2023 (Date of Event Which Requires Filing of this Statement) Check the appropriate box to desi

TCRX / TScan Therapeutics, Inc. / Pitango HealthTech Fund I, L.P. - SC 13G/A Passive Investment

SC 13G/A 1 tm245444d1sc13ga.htm SC 13G/A UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 SCHEDULE 13G/A Under the Securities Exchange Act of 1934 (Amendment No. 1)* TScan Therapeutics, Inc. (Name of Issuer) Common Stock, par value $0.0001 per share (Title of Class of Securities) 89854M101 (CUSIP Number) Ofira Kadmor Senior VP Finance Pitango Venture Capital 11 HaMenofim St.

Exhibit 1 – Joint Filing Agreement pursuant to Rule 13d-1(k)(1)

EX-99.1 2 tm245444d1ex-1.htm EXHIBIT 1 EXHIBIT 1 JOINT FILING AGREEMENT The undersigned parties hereby agree that this Amendment No. 1 to the Statement of Beneficial Ownership on Schedule 13G filed herewith by the undersigned parties, relating to the common stock, par value $0.0001 per share of TScan Therapeutics, Inc., is being filed jointly with the Securities and Exchange Commission pursuant to

TCRX / TScan Therapeutics, Inc. / ADAGE CAPITAL PARTNERS GP, L.L.C. - TSCAN THERAPEUTICS, INC. Passive Investment

SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 SCHEDULE 13G/A Under the Securities Exchange Act of 1934 (Amendment No. 1)* TScan Therapeutics, Inc. (Name of Issuer) Voting Common Stock, par value $0.0001 per share (Title of Class of Securities) 89854M101 (CUSIP Number) December 31, 2023 (Date of Event Which Requires Filing of This Statement) Check the appropriate box to designate the ru

TScan Therapeutics Appoints Seasoned Industry Executive Jason A. Amello as Chief Financial Officer

Exhibit 99.1 TScan Therapeutics Appoints Seasoned Industry Executive Jason A. Amello as Chief Financial Officer WALTHAM, Mass., January 29, 2024 — TScan Therapeutics, Inc. (Nasdaq: TCRX), a clinical-stage biopharmaceutical company focused on the development of T cell receptor (TCR)-engineered T cell therapies (TCR-T) for the treatment of patients with cancer, today announced the appointment of Jas

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 24, 2024 TSCAN 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) January 24, 2024 TSCAN THERAPEUTICS, INC. (Exact name of registrant as specified in its charter) Delaware 001-40603 82-5282075 (State or other jurisdiction of incorporation) (Commissio

Disclaimers and forward-looking statements This presentation and the accompanying discussion contain forward-looking statements within the meaning of the Private Securities Litigation Reform Act of 1995, including, but not limited to, express or impl

TScan Therapeutics KOL event: Dec. 11, 2023 Exhibit 99.2 Disclaimers and forward-looking statements This presentation and the accompanying discussion contain forward-looking statements within the meaning of the Private Securities Litigation Reform Act of 1995, including, but not limited to, express or implied statements regarding the Company’s plans, progress, and timing relating to the Company’s

TScan Therapeutics Presents Initial Phase 1 Clinical Results on TSC-100 and TSC-101 at the 65th American Society of Hematology Annual Meeting and Exposition No relapses have occurred in six of six treatment-arm patients, four with follow-up past six

Exhibit 99.1 TScan Therapeutics Presents Initial Phase 1 Clinical Results on TSC-100 and TSC-101 at the 65th American Society of Hematology Annual Meeting and Exposition No relapses have occurred in six of six treatment-arm patients, four with follow-up past six months; one of four control-arm patients relapsed at six months and two others required clinical intervention No patient-derived hematopo

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 9, 2023 TSCAN 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) December 9, 2023 TSCAN THERAPEUTICS, INC. (Exact name of registrant as specified in its charter) Delaware 001-40603 82-5282075 (State or other jurisdiction of incorporation) (Commissio

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 6, 2023 TSCAN 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) December 6, 2023 TSCAN THERAPEUTICS, INC. (Exact name of registrant as specified in its charter) Delaware 001-40603 82-5282075 (State or other jurisdiction of incorporation) (Commissio

TScan Therapeutics Appoints R. Keith Woods to its Board of Directors, Bringing Expertise in Commercialization and Global Operations

EX-99.1 Exhibit 99.1 TScan Therapeutics Appoints R. Keith Woods to its Board of Directors, Bringing Expertise in Commercialization and Global Operations WALTHAM, Mass., Dec 7, 2023 — TScan Therapeutics, Inc. (Nasdaq: TCRX), a clinical-stage biopharmaceutical company focused on the development of T cell receptor (TCR)-engineered T cell therapies (TCR-T) for the treatment of patients with cancer, to

First Amendment to Lease by and between PPF OFF 828-830 Winter Street LLC and the Registrant, dated November 8, 2023 (incorporated by reference to Exhibit 10.1 to the Registrant’s Quarterly Report on Form 10-Q, filed with the Securities and Exchange Commission on November 9, 2023).

Exhibit 10.1 830 WINTER STREET WALTHAM, MASSACHUSETTS (the “Building”) FIRST AMENDMENT (“First Amendment”) EXECUTION DATE: November 8, 2023 (the “Execution Date”) LANDLORD: PPF OFF 828-830 Winter Street LLC, a Delaware limited liability company TENANT: TScan Therapeutics, Inc., a Delaware corporation PREMISES: Approximately 25,472 rentable square feet of space in the Building, consisting of approx

TScan Therapeutics Reports Third Quarter 2023 Financial Results and Provides Corporate Update Company to present poster on initial data from heme malignancies Phase 1 trial at the 65th ASH Annual Meeting and Exposition; Company to host virtual KOL ev

Exhibit 99.1 TScan Therapeutics Reports Third Quarter 2023 Financial Results and Provides Corporate Update Company to present poster on initial data from heme malignancies Phase 1 trial at the 65th ASH Annual Meeting and Exposition; Company to host virtual KOL event on Monday, December 11, 2023, at 8:00 a.m. ET Announced recent FDA clearance of IND for TSC-203-A0201 targeting PRAME Presented six p

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 TSCAN THERAPEUTICS, INC. (Exact name of registrant as specified in its charter) Delaware 001-40603 82-5282075 (State or other jurisdiction of incorporation) (Commissio

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

UNITED STATES SECURITIES AND EXCHANGE COMMISSION WASHINGTON, D.C. 20549 FORM 10-Q (Mark One) ☒ 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 ☐ 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: 001-40603 TSCAN

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) August 10, 2023 TSCAN THERAPEUTICS, INC. (Exact name of registrant as specified in its charter) Delaware 001-40603 82-5282075 (State or other jurisdiction of incorporation) (Commission

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

UNITED STATES SECURITIES AND EXCHANGE COMMISSION WASHINGTON, D.C. 20549 FORM 10-Q (Mark One) ☒ 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 ☐ 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: 001-40603 TSCAN THER

TScan Therapeutics Reports Second Quarter 2023 Financial Results and Provides Corporate Update Presented preliminary Phase 1 clinical data from heme malignancies trial at the ASGCT 26th Annual Meeting; expect to reach recommended Phase 2 dose for two

Exhibit 99.1 TScan Therapeutics Reports Second Quarter 2023 Financial Results and Provides Corporate Update Presented preliminary Phase 1 clinical data from heme malignancies trial at the ASGCT 26th Annual Meeting; expect to reach recommended Phase 2 dose for two TCR-T therapy product candidates and report interim data by year-end 2023 Announced FDA clearance of fourth IND for solid tumor program

Collaboration Agreement by and between the Registrant and Amgen, Inc., dated as of May 8, 2023 (incorporated by reference to Exhibit 10.1 to the Registrant’s Quarterly Report on Form 10-Q, filed with the Securities and Exchange Commission on August 10, 2023).

Exhibit 10.1 CONFIDENTIAL FOR DISCUSSION PURPOSES ONLY EXECUTION VERSION CERTAIN CONFIDENTIAL INFORMATION CONTAINED IN THIS DOCUMENT, MARKED BY [***], HAS BEEN OMITTED BECAUSE IT IS BOTH (I) NOT MATERIAL AND (II) IS THE TYPE THAT THE REGISTRANT TREATS AS PRIVATE OR CONFIDENTIAL. Research Collaboration and License Agreement This Research Collaboration and License Agreement (“Agreement”) is made and

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 20, 2023 TSCAN 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 20, 2023 TSCAN THERAPEUTICS, INC. (Exact name of registrant as specified in its charter) Delaware 001-40603 82-5282075 (State or other jurisdiction of incorporation) (Commission F

TScan Therapeutics Announces Transition of Chief Financial Officer

EX-99.1 Exhibit 99.1 TScan Therapeutics Announces Transition of Chief Financial Officer WALTHAM, Mass., June 29, 2023 — TScan Therapeutics, Inc. (Nasdaq: TCRX), a clinical-stage biopharmaceutical company focused on the development of T cell receptor (TCR)-engineered T cell therapies (TCR-Ts) for the treatment of patients with cancer, today announced that its Chief Financial Officer, Brian M. Silve

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, 2023 TSCAN 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 27, 2023 TSCAN THERAPEUTICS, INC. (Exact name of registrant as specified in its charter) Delaware 001-40603 82-5282075 (State or other jurisdiction of incorporation) (Commission F

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, 2023 TSCAN 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 13, 2023 TSCAN THERAPEUTICS, INC. (Exact name of registrant as specified in its charter) Delaware 001-40603 82-5282075 (State or other jurisdiction of incorporation) (Commission F

As filed with the Securities and Exchange Commission on June 16, 2023

S-8 As filed with the Securities and Exchange Commission on June 16, 2023 Registration No.

Amendment No. 1 to the TScan Therapeutics, Inc. 2021 Equity Incentive Plan (Incorporated by reference to Exhibit 10.1 to the Registrant’s Current Report on Form 8-K (File No. 001-40603) filed with the Securities and Exchange Commission on June 16, 2023.

EX-10.1 Exhibit 10.1 AMENDMENT NO. 1 TO THE TSCAN THERAPEUTICS, INC. 2021 EQUITY INCENTIVE PLAN WHEREAS, TScan Therapeutics, Inc. (the “Company”) maintains the TScan Therapeutics, Inc. 2021 Equity Incentive Plan (the “Plan”), which was previously adopted by the Board of Directors of the Company (the “Board”) and approved by the stockholders of the Company; WHEREAS, the Board desires to amend the P

Filing Fee Table.

EX-FILING FEES Exhibit 107.1 Calculation of Filing Fee Tables Form S-8 (Form Type) TScan Therapeutics, Inc. (Exact Name of Registrant as Specified in its Charter) Table 1: Newly Registered Securities Security Type Security Class Title Fee Calculation Rule Amount Registered(1) Proposed Maximum Offering Price per Share Maximum Aggregate Offering Price Fee Rate Amount of Registration Fee Equity Commo

TCRX / Tscan Therapeutics Inc / ADAGE CAPITAL PARTNERS GP, L.L.C. - TSCAN THERAPEUTICS, INC. Passive Investment

SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 SCHEDULE 13G Under the Securities Exchange Act of 1934 (Amendment No. )* TScan Therapeutics, Inc. (Name of Issuer) Voting Common Stock, par value $0.0001 per share (Title of Class of Securities) 89854M101 (CUSIP Number) May 31, 2023 (Date of Event Which Requires Filing of This Statement) Check the appropriate box to designate the rule pursu

TCRX / Tscan Therapeutics Inc / BlackRock Inc. Passive Investment

us89854m1018060623.txt SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 SCHEDULE 13G Under the Securities Exchange Act of 1934 (Amendment No: 2) TScan Therapeutics, Inc. - (Name of Issuer) Common Stock - (Title of Class of Securities) 89854M101 - (CUSIP Number) May 31, 2023 - (Date of Event Which Requires Filing of this Statement) Check the appropriate box to designate the rule pursuant t

Joint Filing Agreement

Exhibit 99.1 Joint Filing Agreement The undersigned hereby agree that the Statement on Schedule 13G dated June 5, 2023 with respect to the Voting Common Stock, $0.0001 par value per share, of TScan Therapeutics, Inc., a Delaware corporation, and any further amendments thereto executed by each and any of the undersigned shall be filed on behalf of each of the undersigned pursuant to and in accordan

TCRX / Tscan Therapeutics Inc / BIOTECHNOLOGY VALUE FUND L P - SCHEDULE 13G Passive Investment

UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 SCHEDULE 13G (Rule 13d-102) INFORMATION TO BE INCLUDED IN STATEMENTS FILED PURSUANT TO RULES 13d-1(b), (c), AND (d) AND AMENDMENTS THERETO FILED PURSUANT TO RULE 13d-2(b) (Amendment No. )1 TScan Therapeutics, Inc. (Name of Issuer) Voting Common Stock, $0.0001 par value per share (Title of Class of Securities) 89854M101 (CUSIP

TCRX / Tscan Therapeutics Inc / EcoR1 Capital, LLC Passive Investment

UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 SCHEDULE 13G Under the Securities Exchange Act of 1934 (Amendment No. ) TScan Therapeutics, Inc. (Name of Issuer) Voting Common Stock, par value $0.0001 per share (Title of Class of Securities) 89854M101 (CUSIP Number) May 26, 2023 (Date of Event Which Requires Filing of this Statement) Check the appropriate box to designate t

TCRX / Tscan Therapeutics Inc / BAKER BROS. ADVISORS LP - SC 13D/A Activist Investment

UNITED STATES SECURITIES AND EXCHANGE COMMISSION WASHINGTON, DC 20549 SCHEDULE 13D (Rule 13d-102) INFORMATION TO BE INCLUDED IN STATEMENTS FILED PURSUANT TO RULE 13d-l(a) AND AMENDMENTS THERETO FILED PURSUANT TO RULE 13d-2(a) (Amendment No.

JOINT FILING AGREEMENT

EX-99 2 p23-1699exhibit99.htm JOINT FILING AGREEMENT Exhibit 99.1 JOINT FILING AGREEMENT The undersigned acknowledge and agree that the foregoing statement on Schedule 13G is filed on behalf of each of the undersigned and that all subsequent amendments to this statement on Schedule 13G shall be filed on behalf of each of the undersigned without the necessity of filing additional joint filing agree

TCRX / Tscan Therapeutics Inc / Lynx1 Capital Management LP - TSCAN THERAPEUTICS, INC.. Passive Investment

SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 SCHEDULE 13G Under the Securities Exchange Act of 1934 (Amendment No. )* TScan Therapeutics, Inc. (Name of Issuer) Voting Common Stock, $0.0001 par value per share (Title of Class of Securities) 89854M101 (CUSIP Number) May 31, 2023 (Date of Event Which Requires Filing of this Statement) Check the appropriate box to designate the rule pursu

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. )

DEFA14A 1 d501127ddefa14a.htm DEFA14A 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 Co

TScan Therapeutics Appoints Gavin MacBeath, Ph.D. as Chief Executive Officer and as a Member of the Board of Directors

EX-99.1 Exhibit 99.1 TScan Therapeutics Appoints Gavin MacBeath, Ph.D. as Chief Executive Officer and as a Member of the Board of Directors WALTHAM, Mass., May 24 , 2023 — TScan Therapeutics, Inc. (Nasdaq: TCRX) (TScan), a clinical-stage biopharmaceutical company focused on the development of T cell receptor (TCR)-engineered T cell therapies (TCR-T) for the treatment of patients with cancer, today

Exhibit 4.1 to the Issuer’s Current Report on Form 8-K, filed with the SEC on May 31, 2023

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 25, 2023 TSCAN THERAPEUTICS, INC. (Exact name of registrant as specified in its charter) Delaware 001-40603 82-5282075 (State or other jurisdiction of incorporation) (Commission Fi

TScan Therapeutics Announces Launch of Proposed Public Offering

EX-99.1 Exhibit 99.1 TScan Therapeutics Announces Launch of Proposed Public Offering WALTHAM, Mass., May 25, 2023 — TScan Therapeutics, Inc. (Nasdaq: TCRX), a clinical-stage biopharmaceutical company focused on the development of T cell receptor (TCR)-engineered T cell therapies (TCR-T) for the treatment of patients with cancer, today announced that it has commenced an underwritten public offering

Form of Pre-Funded Warrant (incorporated by reference to Exhibit 4.1 to the Registrant's Current Report on Form 8-K, filed with the Securities and Exchange Commission on May 31, 2023).

EX-4.1 Exhibit 4.1 TSCAN THERAPEUTICS, INC. FORM OF PRE-FUNDED WARRANT TO PURCHASE COMMON STOCK Number of Shares: [ ] (subject to adjustment) Warrant No. Original Issue Date: [ ], 2023 TScan Therapeutics, Inc., a Delaware corporation (the “Company”), hereby certifies that, for good and valuable consideration, the receipt and sufficiency of which are hereby acknowledged, [ ] or its registered assig

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 24, 2023 TSCAN THERAPEUTICS, I

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 24, 2023 TSCAN THERAPEUTICS, INC. (Exact name of registrant as specified in its charter) Delaware 001-40603 82-5282075 (State or other jurisdiction of incorporation) (Commission Fi

Underwriting Agreement dated May 25, 2023.

EX-1.1 Exhibit 1.1 EXECUTION VERSION 22,989,474 SHARES OF COMMON STOCK (PAR VALUE $0.0001 PER SHARE) PRE-FUNDED WARRANTS TO PURCHASE 47,010,526 SHARES OF COMMON STOCK TScan Therapeutics, Inc. UNDERWRITING AGREEMENT May 25, 2023 May 25, 2023 Morgan Stanley & Co. LLC Wedbush Securities Inc. as Representatives of the several Underwriters listed in Schedule II hereto c/o Morgan Stanley & Co. LLC 1585

TScan Therapeutics Announces Pricing of $140 Million Public Offering

EX-99.2 Exhibit 99.2 TScan Therapeutics Announces Pricing of $140 Million Public Offering WALTHAM, Mass., May 26, 2023 — TScan Therapeutics, Inc. (Nasdaq: TCRX), a clinical-stage biopharmaceutical company focused on the development of T cell receptor (TCR)-engineered T cell therapies (TCR-T) for the treatment of patients with cancer, today announced the pricing of an underwritten public offering o

22,989,474 Shares of Common Stock Pre-Funded Warrants to Purchase 47,010,526 Shares of Common Stock

Table of Contents Filed Pursuant to Rule 424(b)(5) Registration No. 333-268260 PROSPECTUS SUPPLEMENT (To Prospectus Dated May 16, 2023) 22,989,474 Shares of Common Stock Pre-Funded Warrants to Purchase 47,010,526 Shares of Common Stock We are offering 22,989,474 shares of our voting common stock and pre-funded warrants to purchase 47,010,526 shares of voting common stock in this offering. Our voti

TScan Therapeutics, Inc.

FWP Free Writing Prospectus Filed Pursuant to Rule 433 To Prospectus dated May 16, 2023 Preliminary Prospectus Supplement dated May 25, 2023 Registration Statement File No.

Shares of Common Stock Pre-Funded Warrants to Purchase Shares of Common Stock

424B5 Table of Contents Filed Pursuant to Rule 424(b)(5) Registration No. 333-268260 This preliminary prospectus supplement and the accompanying prospectus relate to an effective registration statement under the Securities Act of 1933, as amended, but the information in this prospectus supplement is not complete and may be changed. This preliminary prospectus supplement and the accompanying prospe

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 17, 2023 TSCAN THERAPEUTICS, I

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 17, 2023 TSCAN THERAPEUTICS, INC. (Exact name of registrant as specified in its charter) Delaware 001-40603 82-5282075 (State or other jurisdiction of incorporation) (Commission Fi

TScan Therapeutics Presents Preliminary Phase 1 Clinical Results on TSC-100 and TSC-101 at the American Society of Gene & Cell Therapy 26th Annual Meeting Poster highlights Phase 1 results following treatment with TSC-100 and TSC-101 after hematopoie

EX-99.1 Exhibit 99.1 TScan Therapeutics Presents Preliminary Phase 1 Clinical Results on TSC-100 and TSC-101 at the American Society of Gene & Cell Therapy 26th Annual Meeting Poster highlights Phase 1 results following treatment with TSC-100 and TSC-101 after hematopoietic cell transplantation Company to host a virtual KOL event featuring Monzr M. Al Malki, M.D., to discuss highlights from the me

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 16, 2023 TSCAN THERAPEUTICS, I

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 16, 2023 TSCAN THERAPEUTICS, INC. (Exact name of registrant as specified in its charter) Delaware 001-40603 82-5282075 (State or other jurisdiction of incorporation) (Commission Fi

Sales Agreement, by and between TScan Therapeutics, Inc. and Wedbush Securities Inc., dated May 16, 2023.

Exhibit 1.1 TSCAN THERAPEUTICS, INC. Common Stock Sales Agreement May 16, 2023 Wedbush Securities Inc. 1000 Wilshire Blvd. Los Angeles, CA 90017 Ladies and Gentlemen: TScan Therapeutics, Inc., a Delaware corporation (the “Company”), confirms its agreement (this “Agreement”) with Wedbush Securities Inc. (“Wedbush”), as follows: 1. Issuance and Sale of Placement Shares. The Company agrees that, from

TSCAN THERAPEUTICS, INC. May 16, 2023

TSCAN THERAPEUTICS, INC. May 16, 2023 VIA EDGAR Securities and Exchange Commission Division of Corporation Finance 100 F. Street N.E. Washington, D.C. 20549 Re: TScan Therapeutics, Inc. (CIK 0001783328) Request to Withdraw Pre-Effective Amendment No. 1 to Registration Statement (Reg No. 333-268260) on Form S-3 (Accession No. 0001193125-23-145261) Ladies and Gentlemen: Pursuant to Rule 477 promulga

As filed with the Securities and Exchange Commission on May 15, 2023

S-3/A As filed with the Securities and Exchange Commission on May 15, 2023 Registration No.

As filed with the Securities and Exchange Commission on May 15, 2023

S-3/A As filed with the Securities and Exchange Commission on May 15, 2023 Registration No.

As filed with the Securities and Exchange Commission on May 15, 2023

S-3/A As filed with the Securities and Exchange Commission on May 15, 2023 Registration No.

Up to $75,000,000 Common Stock

Table of Contents Filed pursuant to Rule 424(b)(5) Registration No. 333-268260 PROSPECTUS SUPPLEMENT (To Prospectus dated May 16, 2023) Up to $75,000,000 Common Stock We have entered into a sales agreement, dated as of May 16, 2023, or Sales Agreement, with Wedbush Securities Inc., or Wedbush, relating to shares of our voting common stock, par value $0.0001 per share, offered by this prospectus su

TScan Therapeutics, Inc. 830 Winter Street Waltham, Massachusetts 02451

TScan Therapeutics, Inc. 830 Winter Street Waltham, Massachusetts 02451 May 15, 2023 Via EDGAR Transmission U.S. Securities and Exchange Commission Division of Corporation Finance 100 F Street, N.E. Washington, D.C. 20549 Re: TScan Therapeutics, Inc. Acceleration Request for Registration Statement on Form S-3 (File No. 333-268261) Ladies and Gentlemen: Pursuant to Rule 461 under the Securities Act

TScan Therapeutics, Inc. 830 Winter Street Waltham, Massachusetts 02451

CORRESP TScan Therapeutics, Inc. 830 Winter Street Waltham, Massachusetts 02451 May 15, 2023 Via EDGAR Transmission U.S. Securities and Exchange Commission Division of Corporation Finance 100 F Street, N.E. Washington, D.C. 20549 Re: TScan Therapeutics, Inc. Acceleration Request for Registration Statement on Form S-3 (File No. 333-268260) Ladies and Gentlemen: Pursuant to Rule 461 under the Securi

TScan Therapeutics, Inc. 830 Winter Street Waltham, Massachusetts 02451

CORRESP TScan Therapeutics, Inc. 830 Winter Street Waltham, Massachusetts 02451 May 10, 2023 Via EDGAR Transmission U.S. Securities and Exchange Commission Division of Corporation Finance 100 F Street, N.E. Washington, D.C. 20549 Re: TScan Therapeutics, Inc. Acceleration Request for Registration Statement on Form S-3 (File No. 333-268261) Ladies and Gentlemen: Pursuant to Rule 461 under the Securi

TScan Therapeutics Reports First Quarter 2023 Financial Results and Provides Corporate Update Entered into partnership with Amgen to identify novel targets in Crohn’s disease; TScan to receive $30 million upfront Enrolled patients in all three arms o

EX-99.1 TScan Therapeutics Reports First Quarter 2023 Financial Results and Provides Corporate Update Entered into partnership with Amgen to identify novel targets in Crohn’s disease; TScan to receive $30 million upfront Enrolled patients in all three arms of Phase 1 hematologic malignancies study; TSC-101 progressing to second dose level Announced upcoming trial-in-progress poster presentation on

Form 10-Q

UNITED STATES SECURITIES AND EXCHANGE COMMISSION WASHINGTON, D.C. 20549 FORM 10-Q (Mark One) ☒ 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: 001-40603 TSCAN THE

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) May 10, 2023 TSCAN THERAPEUTICS, INC. (Exact name of registrant as specified in its charter) Delaware 001-40603 82-5282075 (State or other jurisdiction of incorporation) (Commission Fi

TScan Therapeutics, Inc. 830 Winter Street Waltham, Massachusetts 02451

CORRESP TScan Therapeutics, Inc. 830 Winter Street Waltham, Massachusetts 02451 May 10, 2023 Via EDGAR Transmission U.S. Securities and Exchange Commission Division of Corporation Finance 100 F Street, N.E. Washington, D.C. 20549 Re: TScan Therapeutics, Inc. Acceleration Request for Registration Statement on Form S-3 (File No. 333-268260) Ladies and Gentlemen: Pursuant to Rule 461 under the Securi

AMGEN AND TSCAN THERAPEUTICS ANNOUNCE COLLABORATION TO IDENTIFY NOVEL TARGETS IN CROHN’S DISEASE Collaboration Brings Together TScan’s Proprietary Target Discovery Platform and Amgen’s Inflammation Therapeutic Expertise and Research Capabilities TSca

EX-99.1 Exhibit 99.1 News Release AMGEN AND TSCAN THERAPEUTICS ANNOUNCE COLLABORATION TO IDENTIFY NOVEL TARGETS IN CROHN’S DISEASE Collaboration Brings Together TScan’s Proprietary Target Discovery Platform and Amgen’s Inflammation Therapeutic Expertise and Research Capabilities TScan to Receive $30 Million Upfront With Potential Development and Commercial Milestone Payments of Over $500 Million T

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 8, 2023 TSCAN THERAPEUTICS, IN

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 8, 2023 TSCAN THERAPEUTICS, INC. (Exact name of registrant as specified in its charter) Delaware 001-40603 82-5282075 (State or other jurisdiction of incorporation) (Commission Fil

definitive proxy statement

DEF 14A Table of Contents UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.

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. )

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. ) 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 14a-6(e)(2))

ARS

UNITEDSTATES SECURITIESANDEXCHANGECOMMISSION Washington,D.C.20549 FORM10-K (MarkOne) ☒ ANNUALREPORTPURSUANTTOSECTION13OR15(d)OFTHESECURITIESEXCHANGEACTOF1934 ForthefiscalyearendedDecember31,2022 or ☐ TRA R R NSITIONREPORTPURSUANTTOSECTION13OR15(d)OFTHESECURITIESEXCHANGEACTOF1934 Forthetransitionperiodfromto CommissionFileNumber001-40603 TSCANTHERAPEUTICS,INC. (ExactnameofRegistrantasspecifiedinits

TScan Therapeutics Announces Appointment of Barbara Klencke, M.D., to its Board of Directors Deepens the Board’s clinical oncology and commercialization expertise as programs for hematologic malignancies and solid tumors advance Company also announce

EX-99.1 Exhibit 99.1 TScan Therapeutics Announces Appointment of Barbara Klencke, M.D., to its Board of Directors Deepens the Board’s clinical oncology and commercialization expertise as programs for hematologic malignancies and solid tumors advance Company also announces key leadership promotions WALTHAM, Mass., April 10, 2023 — TScan Therapeutics, Inc. (Nasdaq: TCRX), a clinical-stage biopharmac

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 6, 2023 TSCAN 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) April 6, 2023 TSCAN THERAPEUTICS, INC. (Exact name of registrant as specified in its charter) Delaware 001-40603 82-5282075 (State or other jurisdiction of incorporation) (Commission F

TSCAN THERAPEUTICS ANNOUNCES CEO TRANSITION David Southwell Steps Down; Gavin MacBeath, Ph.D., Chief Scientific and Operating Officer, to Serve as Acting CEO Company Reaffirms Previously Disclosed Milestones and Cash Runway; Provides Clinical Program

EX-99.1 Exhibit 99.1 TSCAN THERAPEUTICS ANNOUNCES CEO TRANSITION David Southwell Steps Down; Gavin MacBeath, Ph.D., Chief Scientific and Operating Officer, to Serve as Acting CEO Company Reaffirms Previously Disclosed Milestones and Cash Runway; Provides Clinical Program Update WALTHAM, Mass., March 31 2023 — TScan Therapeutics, Inc. (Nasdaq: TCRX) [“TScan” or “The Company”], a clinical-stage biop

Regulation FD Disclosure, Departure of Directors or Certain Officers; Election of Directors; Appointment of Certain Officers; Compensatory Arrangements of Certain Officers, 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) March 27, 2023 TSCAN THERAPEUTICS, INC. (Exact name of registrant as specified in its charter) Delaware 001-40603 82-5282075 (State or other jurisdiction of incorporation) (Commission

Filing Fee Table.

EX-FILING FEES Exhibit 107.1 Calculation of Filing Fee Tables Form S-8 (Form Type) TScan Therapeutics, Inc. (Exact Name of Registrant as Specified in its Charter) Table 1: Newly Registered Securities Security Type Security Class Title Fee Calculation Rule Amount Registered(1) Proposed Maximum Offering Price per Share Maximum Aggregate Offering Price Fee Rate Amount of Registration Fee Equity Commo

As filed with the Securities and Exchange Commission on March 8, 2023

As filed with the Securities and Exchange Commission on March 8, 2023 Registration No.

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

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 08, 2023 TSCAN THERAPEUTICS, INC. (Exact name of registrant as specified in its charter) Delaware 001-40603 82-5282075 (State or other jurisdiction of incorporation) (Commission

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 001-40603 TSCAN THERAPEUT

TScan Therapeutics Reports Fourth Quarter and Full Year 2022 Financial Results and Highlights Upcoming Milestones Phase 1 umbrella trial for TSC-100 and TSC-101 in hematologic malignancies on track to enroll patients into each of the three study arms

Exhibit 99.1 TScan Therapeutics Reports Fourth Quarter and Full Year 2022 Financial Results and Highlights Upcoming Milestones Phase 1 umbrella trial for TSC-100 and TSC-101 in hematologic malignancies on track to enroll patients into each of the three study arms and provide a clinical update including safety and biomarker data by mid-year 2023 Clearance of primary IND (T-Plex) in addition to two

TCRX / TScan Therapeutics, Inc. / HILLHOUSE CAPITAL MANAGEMENT, LTD. - TSCAN THERAPEUTICS, INC. Passive Investment

SC 13G/A 1 p23-0185sc13ga.htm TSCAN THERAPEUTICS, INC. SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 SCHEDULE 13G/A Under the Securities Exchange Act of 1934 (Amendment No. 1)* TScan Therapeutics, Inc. (Name of Issuer) Voting Common Stock, par value $0.0001 per share (Title of Class of Securities) 89854M101 (CUSIP Number) December 31, 2022 (Date of Event Which Requires Filing of This S

TCRX / TScan Therapeutics, Inc. / BlackRock Inc. Passive Investment

us89854m1018020323.txt SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 SCHEDULE 13G Under the Securities Exchange Act of 1934 (Amendment No: 1) TScan Therapeutics, Inc. - (Name of Issuer) Common Stock - (Title of Class of Securities) 89854M101 - (CUSIP Number) December 31, 2022 - (Date of Event Which Requires Filing of this Statement) Check the appropriate box to designate the rule pursu

TScan Therapeutics Announces FDA Clearance of Three Investigational New Drug Applications for the Treatment of Solid Tumors Primary IND for solid tumor program, T-Plex, supports simultaneous use of multiple TCRs to create customized, multiplexed TCR-

Exhibit 99.1 TScan Therapeutics Announces FDA Clearance of Three Investigational New Drug Applications for the Treatment of Solid Tumors Primary IND for solid tumor program, T-Plex, supports simultaneous use of multiple TCRs to create customized, multiplexed TCR-T cell therapies based on target and HLA expression INDs for TSC-204-A0201 and TSC-204-C0702 introduce the first two TCRs into TScan’s Im

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 23, 2023 TSCAN 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) January 23, 2023 TSCAN THERAPEUTICS, INC. (Exact name of registrant as specified in its charter) Delaware 001-40603 82-5282075 (State or other jurisdiction of incorporation) (Commissio

LETTER

United States securities and exchange commission logo November 15, 2022 David Southwell President and Chief Executive Officer TScan Therapeutics, Inc.

LETTER

United States securities and exchange commission logo November 15, 2022 David Southwell President and Chief Executive Officer TScan Therapeutics, Inc.

Power of Attorney (included in the signature pages to the Registration Statement)

Table of Contents As filed with the Securities and Exchange Commission on November 9, 2022 Registration No.

Form of Senior Indenture between Registrant and one or more trustees to be named.

Exhibit 4.4 TSCAN THERAPEUTICS, INC. Issuer AND [TRUSTEE], Trustee INDENTURE Dated as of [?], 202[?] Senior Debt Securities TABLE OF CONTENTS1 Page Article 1 DEFINITIONS 1 Section 1.01 Definitions of Terms 1 Article 2 ISSUE, DESCRIPTION, TERMS, EXECUTION, REGISTRATION AND EXCHANGE OF SECURITIES 4 Section 2.01 Designation and Terms of Securities 4 Section 2.02 Form of Securities and Trustee?s Certi

TScan Therapeutics Reports Third Quarter 2022 Financial Results and Provides Business Update Four sites for hematologic malignancies program open and enrolling patients Completed pre-IND meeting with the FDA for solid tumor program; virtual investor

TScan Therapeutics Reports Third Quarter 2022 Financial Results and Provides Business Update Four sites for hematologic malignancies program open and enrolling patients Completed pre-IND meeting with the FDA for solid tumor program; virtual investor event Monday, November 14, at 5:00 PM ET to highlight clinical trial design Ended quarter with cash and cash equivalents of $137.

Filing Fee Table (incorporated by reference to Exhibit 107 to the Registrant’s Registration Statement on Form S-3 filed with the Securities and Exchange Commission on November 9, 2022).

Exhibit 107 CALCULATION OF REGISTRATION FEE TScan Therapeutics, Inc. (Exact name of Registrant as Specified in its Charter) Table 1: Newly Registered and Carry Forward Securities (Form S-3) 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 For

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

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 09, 2022 TSCAN THERAPEUTICS, INC. (Exact name of Registrant as Specified in Its Charter) Delaware 001-40603 82-5282075 (State or Other Jurisdiction of Incorporation) (Commiss

Form of Subordinated Indenture between Registrant and one or more trustees to be named.

Exhibit 4.5 TSCAN THERAPEUTICS, INC. Issuer AND [TRUSTEE], Trustee INDENTURE Dated as of [?], 202[?] Subordinated Debt Securities TABLE OF CONTENTS(1) Article 1 DEFINITIONS 1 Section 1.01 Definitions of Terms 1 Article 2 ISSUE, DESCRIPTION, TERMS, EXECUTION, REGISTRATION AND EXCHANGE OF SECURITIES 4 Section 2.01 Designation and Terms of Securities 4 Section 2.02 Form of Securities and Trustee?s Ce

Filing Fee Table

Exhibit 107 CALCULATION OF REGISTRATION FEE TScan Therapeutics, Inc. (Exact name of Registrant as Specified in its Charter) Table 1: Newly Registered and Carry Forward Securities (Form S-3) Security Type Security Class Title Fee Calculation or Carry Forward Rule Amount Registered Proposed Maximum Offering Price Per Unit (2) Maximum Aggregate Offering Price Fee Rate Amount of Registration Fee Carry

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

UNITED STATES SECURITIES AND EXCHANGE COMMISSION WASHINGTON, D.C. 20549 FORM 10-Q (Mark One) ☒ QUARTERLY REPORT PURSUANT TO SECTION 13 OR 15(d) OF THE SECURITIES EXCHANGE ACT OF 1934 For the quarterly period ended September 30, 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: 001-40603 TSCAN

As filed with the Securities and Exchange Commission on November 9, 2022

Table of Contents As filed with the Securities and Exchange Commission on November 9, 2022 Registration No.

TCRX / TScan Therapeutics, Inc. / K2 HealthVentures Equity Trust LLC - 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. )* TScan Therapeutics, Inc. (Name of Issuer) Voting Common Stock, $0.0001 par value per share (Title of Class of Securities) 89854M101 (CUSIP Number) September 9, 2022 (Date of Event Which Requires Filing of this Statement) Check the appropriate box to desig

TScan Therapeutics Secures Convertible Debt Facility for up to $60 Million with K2 HealthVentures Financing supports management’s focus on clinical execution and advancing its ImmunoBank Initial $30 million tranche extends cash runway into the second

Exhibit 99.1 TScan Therapeutics Secures Convertible Debt Facility for up to $60 Million with K2 HealthVentures Financing supports management?s focus on clinical execution and advancing its ImmunoBank Initial $30 million tranche extends cash runway into the second quarter of 2024 WALTHAM, Mass., September 12, 2022 ? TScan Therapeutics, Inc. (Nasdaq: TCRX), a clinical-stage biopharmaceutical company

Loan and Security Agreement, dated September 9, 2022, by and among TScan Therapeutics, Inc., K2 HealthVentures LLC and Ankura Trust Company, LLC (incorporated by reference to Exhibit 10.1 to the Registrant’s Current Report on Form 8-K, filed with the Securities and Exchange Commission on September 12, 2022).

Exhibit 10.1 Execution Version LOAN AND SECURITY AGREEMENT This LOAN AND SECURITY AGREEMENT (as amended, restated, supplemented or otherwise modified from time to time, this ?Agreement?) dated as of September 9, 2022 (the ?Closing Date?) is entered into among TSCAN THERAPEUTICS, INC., a Delaware corporation (?Borrower Representative?), and each other Person party hereto as a borrower from time to

Regulation FD Disclosure, Entry into a Material Definitive Agreement, Financial Statements and Exhibits, Creation of a Direct Financial Obligation or an Obligation under an Off-Balance Sheet Arrangement of a Registrant

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 12, 2022 TSCAN THERAPEUTICS, INC. (Exact name of registrant as specified in its charter) Delaware 001-40603 82-5282075 (State or other jurisdiction of incorporation) (Commis

TCRX / TScan Therapeutics, Inc. / RA CAPITAL MANAGEMENT, L.P. - SC 13G/A Passive Investment

UNITED STATES SECURITIES AND EXCHANGE COMMISSION WASHINGTON, D.C. 20549 SCHEDULE 13G/A Under the Securities Exchange Act of 1934 (Amendment No. 1)* TSCAN THERAPEUTICS, INC. (Name of Issuer) Common Stock, par value $0.0001 per share (Title of Class of Securities) 89854M101 (CUSIP Number) August 15, 2022 (Date of Event Which Requires Filing of this Statement) Check the appropriate box to designate t

UNITED STATES SECURITIES AND EXCHANGE COMMISSION WASHINGTON, DC 20549 FORM 10-Q

UNITED STATES SECURITIES AND EXCHANGE COMMISSION WASHINGTON, DC 20549 FORM 10-Q (Mark One) ? QUARTERLY REPORT PURSUANT TO SECTION 13 OR 15(d) OF THE SECURITIES EXCHANGE ACT OF 1934 For the quarterly period ended June 30, 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: 001-40603 TSCAN THERAPEUTICS, INC.

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): August 10, 2022 TSCAN THERAPEUTICS, INC. (Exact name of registrant as specified in its charter) Delaware 001-40603 82-5282075 (State or other jurisdiction of incorporation) (Commissio

Employment Agreement, dated June 8, 2022, by and between the Registrant and Debora Barton (incorporated by reference to Exhibit 10.1 to the Registrant’s Quarterly Report on Form 10-Q filed with the Securities and Exchange Commission on August 10, 2022).

EX-10.1 2 tcrx-ex101.htm EX-10.1 Exhibit 10.1 C Form Employment Agreement THIS AGREEMENT (the “Agreement”) is entered into by and between Debora Barton (the “Executive” or “you”) and TScan Therapeutics, Inc., a Delaware corporation (the “Company”), as of the date all parties hereto have signed the Agreement. Duties and Scope of Employment. (a) Position. For the term of his or her employment under

TScan Therapeutics Reports Second Quarter 2022 Financial Results and Highlights Recent Progress Phase 1 umbrella trial for hematologic malignancies open for enrollment Publication in Cell further validates use of foundational technology to identify n

TScan Therapeutics Reports Second Quarter 2022 Financial Results and Highlights Recent Progress Phase 1 umbrella trial for hematologic malignancies open for enrollment Publication in Cell further validates use of foundational technology to identify novel tumor antigens and effective TCRs TSC-200-A2 (HPV) and TSC-204-C7 (MAGE-A1) IND filings anticipated by year-end 2022 Appointment of Debora Barton, M.

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): July 7, 2022 TSCAN THERAPEUTICS, INC. (Exact name of registrant as specified in its charter) Delaware 001-40603 82-5282075 (State or other jurisdiction of incorporation) (Commission F

Departure of Directors or Certain Officers; Election of Directors; Appointment of Certain Officers; Compensatory Arrangements of Certain Officers, 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 1, 2022 TSCAN THERAPEUTICS, INC. (Exact name of registrant as specified in its charter) Delaware 001-40603 82-5282075 (State or other jurisdiction of incorporation) (Commission F

TScan Therapeutics Announces FDA Clearance of Investigational New Drug Application for TSC-101 for the Treatment of Hematologic Malignancies Study start-up activities now ongoing for all three arms of the Phase 1 umbrella trial of TSC-100 and TSC-101

Exhibit 99.1 TScan Therapeutics Announces FDA Clearance of Investigational New Drug Application for TSC-101 for the Treatment of Hematologic Malignancies Study start-up activities now ongoing for all three arms of the Phase 1 umbrella trial of TSC-100 and TSC-101 WALTHAM, Mass., May 31, 2022 ? TScan Therapeutics, Inc. (Nasdaq: TCRX), a clinical-stage biopharmaceutical company focused on the develo

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): May 31, 2022 TSCAN THERAPEUTICS, INC. (Exact name of registrant as specified in its charter) Delaware 001-40603 82-5282075 (State or other jurisdiction of incorporation) (Commission F

UNITED STATES SECURITIES AND EXCHANGE COMMISSION WASHINGTON, DC 20549 FORM 10-Q

UNITED STATES SECURITIES AND EXCHANGE COMMISSION WASHINGTON, DC 20549 FORM 10-Q (Mark One) ? QUARTERLY REPORT PURSUANT TO SECTION 13 OR 15(d) OF THE SECURITIES EXCHANGE ACT OF 1934 For the quarterly period ended March 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: 001-40603 TSCAN THERAPEUTICS, INC.

TCRX / TScan Therapeutics, Inc. / BAKER BROS. ADVISORS LP - SC 13D/A Activist Investment

UNITED STATES SECURITIES AND EXCHANGE COMMISSION WASHINGTON, DC 20549 SCHEDULE 13D (Rule 13d-102) INFORMATION TO BE INCLUDED IN STATEMENTS FILED PURSUANT TO RULE 13d-l(a) AND AMENDMENTS THERETO FILED PURSUANT TO RULE 13d-2(a) (Amendment No.

TScan Therapeutics Reports First Quarter 2022 Financial Results and Upcoming Anticipated Milestones Preclinical data to be presented at the American Society of Gene & Cell Therapy 25th Annual Meeting; virtual KOL event following the conference Phase

Exhibit 99.1 TScan Therapeutics Reports First Quarter 2022 Financial Results and Upcoming Anticipated Milestones Preclinical data to be presented at the American Society of Gene & Cell Therapy 25th Annual Meeting; virtual KOL event following the conference Phase 1 umbrella trial for leukemia program on track to initiate in the first half of 2022 Ended the first quarter with cash and cash equivalen

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): May 9, 2022 TSCAN THERAPEUTICS, INC. (Exact name of registrant as specified in its charter) Delaware 001-40603 82-5282075 (State or other jurisdiction of incorporation) (Commission Fi

UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 SCHEDULE 14A (Rule 14a-101) INFORMATION REQUIRED IN PROXY STATEMENT SCHEDULE 14A INFORMATION Proxy Statement Pursuant to Section 14(a) of the Securities Exchange Act of 1934

UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 SCHEDULE 14A (Rule 14a-101) INFORMATION REQUIRED IN PROXY STATEMENT SCHEDULE 14A INFORMATION Proxy Statement Pursuant to Section 14(a) of the Securities Exchange Act of 1934 Filed by the Registrant ? Filed by a party other than the Registrant ? Check the appropriate box: ? Preliminary Proxy Statement ? Confidential, for Use of

UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 SCHEDULE 14A (Rule 14a-101) Information Required in Proxy Statement Schedule 14A Information Proxy Statement Pursuant to Section 14(a) of the Securities Exchange Act of 1934

Table of Contents UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 SCHEDULE 14A (Rule 14a-101) Information Required in Proxy Statement Schedule 14A Information Proxy Statement Pursuant to Section 14(a) of the Securities Exchange Act of 1934 Filed by the Registrant ? Filed by a Party other than the Registrant ? Check the appropriate box: ? Preliminary Proxy Statement ? Confid

Filing Fee Table.

Exhibit 107.1 Calculation of Filing Fee Tables Form S-8 (Form Type) TScan Therapeutics, Inc. (Exact Name of Registrant as Specified in its Charter) Table 1: Newly Registered Securities Security Type Security Class Title Fee Calculation Rule Amount Registered(1) Proposed Maximum Offering Price per Share Maximum Aggregate Offering Price Fee Rate Amount of Registration Fee Equity Common Stock, $0.000

TScan Therapeutics Reports Full Year 2021 Financial Results and Highlights Key 2022 Priorities Received FDA clearance of IND for TSC-100 for the treatment of hematologic malignancies Phase 1 umbrella trial for liquid tumor program to initiate in H1 2

Exhibit 99.1 TScan Therapeutics Reports Full Year 2021 Financial Results and Highlights Key 2022 Priorities Received FDA clearance of IND for TSC-100 for the treatment of hematologic malignancies Phase 1 umbrella trial for liquid tumor program to initiate in H1 2022; preliminary data expected in H2 2022 Two INDs for TSC-200 series anticipated by year end Strong balance sheet with cash and cash equ

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 Act of 1934 Date of Report (Date of earliest event reported): March 9, 2022 TSCAN THERAPEUTICS, INC. (Exact name of registrant as specified in its charter) Delaware 001-40603 82-5282075 (State or other jurisdiction of incorporation) (Commission File Numb

As filed with the Securities and Exchange Commission on March 9, 2022

As filed with the Securities and Exchange Commission on March 9, 2022 Registration No.

Exhibit 4.4

Exhibit 4.4 DESCRIPTION OF SECURITIES REGISTERED UNDER SECTION 12 OF THE SECURITIES EXCHANGE ACT OF 1934, AS AMENDED The following description of the securities of TScan 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 of the material terms of our amended and restate

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, 2021 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 001-40603 TSCAN THERAPEUT

Joint Filing Agreement

EXHIBIT 1 Joint Filing Agreement The undersigned acknowledge and agree that the foregoing statement on Schedule 13G is filed on behalf of each of the undersigned and that all subsequent amendments to this statement on Schedule 13G shall be filed on behalf of each of the undersigned without the necessity of filing additional joint filing statements.

TCRX / TScan Therapeutics, Inc. / GV 2017, L.P. - 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. )* TScan Therapeutics, Inc. (Name of Issuer) Voting Common Stock, par value $0.0001 per share (Title of Class of Securities) 89854M101 (CUSIP Number) December 31, 2021 (Date of Event Which Requires Filing of this Statement) Check the appropriate box t

JOINT FILING AGREEMENT

EXHIBIT 1 JOINT FILING AGREEMENT The undersigned parties hereby agree that this Statement on Schedule 13G filed herewith, and any amendments thereto filed hereafter by any of the undersigned parties, relating to the Common Stock, par value $0.

TCRX / TScan Therapeutics, Inc. / HILLHOUSE CAPITAL MANAGEMENT, LTD. Passive Investment

SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 SCHEDULE 13G Under the Securities Exchange Act of 1934 (Amendment No. )* TScan Therapeutics, Inc. (Name of Issuer) Voting Common Stock, par value $0.0001 per share (Title of Class of Securities) 89854M101 (CUSIP Number) December 31, 2021 (Date of Event Which Requires Filing of This Statement) Check the appropriate box to designate the rule

Agreement of Joint Filing

EXHIBIT A Agreement of Joint Filing The undersigned hereby agree that a single Schedule 13G (or any amendment thereto) relating to the Voting Common Stock of TScan Therapeutics, Inc.

Members of Group

Exhibit 2 Members of Group Deer IX & Co. Ltd. Deer IX & Co. L.P. Bessemer Venture Partners IX L.P. Bessemer Venture Partners IX Institutional L.P.

TCRX / TScan Therapeutics, Inc. / Pitango HealthTech Fund I, L.P. - 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. )* TScan Therapeutics, Inc. (Name of Issuer) Common Stock, par value $0.0001 per share (Title of Class of Securities) 89854M101 (CUSIP Number) Ofira Kadmor Senior VP Finance Pitango Venture Capital 11 HaMenofim St. Bldg. B Herzliya 4672562, Israel Tel +972-9

TCRX / TScan Therapeutics, Inc. / Deer IX & Co. Ltd. - 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. )* TScan Therapeutics, Inc. (Name of Issuer) COMMON STOCK, $0.0001 PAR VALUE PER SHARE (Title of Class of Securities) 89854M101 (CUSIP Number) December 31, 2021 (Date of Event Which Requires Filing of this Statement) Check the appropriate box to desig

JOINT FILING AGREEMENT

Exhibit 1 JOINT FILING AGREEMENT The undersigned hereby agree that the foregoing statement on Schedule 13G is filed on behalf of each of the undersigned, and any amendments thereto executed by the undersigned shall be filed on behalf of each of the undersigned without the necessity of filing any additional joint filing agreement.

TCRX / TScan Therapeutics, Inc. / Longwood Fund IV, L.P. - SC 13G Passive Investment

SC 13G 1 d317942dsc13g.htm SC 13G UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 SCHEDULE 13G Under the Securities Exchange Act of 1934 (Amendment No. )* TSCAN THERAPEUTICS, INC. (Name of Issuer) Voting Common Stock, $0.0001 par value per share (Title of Class of Securities) 89854M101 (CUSIP Number) December 31, 2021 (Date of Event which Requires Filing of this Statement)

TCRX / TScan Therapeutics, Inc. / BlackRock Inc. Passive Investment

SC 13G 1 us89854m1018020422.txt us89854m1018020422.txt SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 SCHEDULE 13G Under the Securities Exchange Act of 1934 (Amendment No: ) TScan Therapeutics, Inc. - (Name of Issuer) Common Stock - (Title of Class of Securities) 89854M101 - (CUSIP Number) December 31, 2021 - (Date of Event Which Requires Filing of this Statement) Check the appropriate

TScan Therapeutics Announces FDA Clearance of Investigational New Drug Application for TSC-100 for the Treatment of Hematologic Malignancies - Phase 1 trial of TSC-100 expected to initiate in the first half of 2022 – - IND for TSC-101 on hold pending

Exhibit 99.1 TScan Therapeutics Announces FDA Clearance of Investigational New Drug Application for TSC-100 for the Treatment of Hematologic Malignancies - Phase 1 trial of TSC-100 expected to initiate in the first half of 2022 ? - IND for TSC-101 on hold pending additional assessment of the risk of off-tumor reactivity ? WALTHAM, Mass., Jan. 24, 2022 ? TScan Therapeutics, Inc. (Nasdaq: TCRX), a b

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): January 24, 2022 TSCAN THERAPEUTICS, INC. (Exact name of registrant as specified in its charter) Delaware 001-40603 82-5282075 (State or other jurisdiction of incorporation) (Commissi