Exhibit 99.1 Mersana Therapeutics Provides Business Update and Announces Fourth Quarter and Full Year 2023 Financial Results CAMBRIDGE, Mass., February 28, 2024 – Mersana Therapeutics, Inc. (NASDAQ: MRSN), a clinical-stage biopharmaceutical company focused on discovering and developing a pipeline of antibody-drug conjugates (ADCs) targeting cancers in areas of high unmet medical need, today provided a business update and reported financial results for the fourth quarter and full year ended December 31, 2023 ...

Mersana Therapeutics, Inc. (NASDAQ:MRSN) Q3 2023 Earnings Conference Call November 7, 2023 8:00 AM ET Company Participants Jason Fredette - SVP, IR & Corporate Communications Martin Huber - President, CEO & Director Brian DeSchuytner - SVP, CFO & COO Conference Call Participants Jonathan Chang - Leerink Partners Colleen Kusy - Baird Ashiq Mubarack - Citigroup Boris Peaker - TD Cowen Kaveri Pohlman - BTIG Karina Rabayeva - Truist Operator Good morning, and welcome to the Mersana Therapeutics Third Quarter 20 ...

UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 FORM 10-Q ☒ QUARTERLY REPORT PURSUANT TO SECTION 13 OR 15(d) OF THE SECURITIES EXCHANGE ACT OF 1934 For the quarterly period ended 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 001-38129 Mersana Therapeutics, Inc. (Exact name of registrant as specified in its charter) (State or other jurisdiction of incorporation o ...

UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 FORM 10-Q ☒ QUARTERLY REPORT PURSUANT TO SECTION 13 OR 15(d) OF THE SECURITIES EXCHANGE ACT OF 1934 For the quarterly period ended 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 001-38129 Mersana Therapeutics, Inc. (Exact name of registrant as specified in its charter) (State or other jurisdiction of incorporation or org ...

Mersana Therapeutics, Inc. (NASDAQ:MRSN) Q1 2023 Earnings Conference Call May 9, 2023 8:00 AM ET Company Participants Jason Fredette – Senior Vice President, Investor Relations and Corporate Communications Anna Protopapas – President and Chief Executive Officer Arvin Yang – Chief Medical Officer Brian DeSchuytner – Chief Financial Officer Conference Call Participants Brian Cheng – J.P. Morgan Jonathan Chang – SVB Securities Colleen Kusy – Baird Kaveri Pohlman – BTIG Ashiq Mubarack – Citi Boris Peaker – Cowe ...

UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 FORM 10-Q ☒ QUARTERLY REPORT PURSUANT TO SECTION 13 OR 15(d) OF THE SECURITIES EXCHANGE ACT OF 1934 For the quarterly period ended March 31, 2023 OR ☐ TRANSITION REPORT PURSUANT TO SECTION 13 OR 15(d) OF THE SECURITIES EXCHANGE ACT OF 1934 For the transition period from to Commission file number 001-38129 Mersana Therapeutics, Inc. (Exact name of registrant as specified in its charter) (State or other jurisdiction of incorporation or or ...

February 1, 2023 Mersana may not actually achieve the plans, intentions or expectations disclosed in these forward-looking statements, and you should not place undue reliance on these forward-looking statements. Actual results or events could differ materially from the plans, intentions and expectations disclosed in these forward-looking statements as a result of various factors, including, among other things, uncertainties inherent in research and development, in the initiation and advancement of clinical ...

Mersana Therapeutics, Inc. (NASDAQ:MRSN) Q4 2022 Earnings Conference Call February 28, 2023 8:00 AM ET Company Participants Jason Fredette - SVP, IR and Corporate Communications Anna Protopapas - President and CEO Arvin Yang - Chief Medical Officer Brian DeSchuytner - CFO Conference Call Participants Jonathan Chang - SVB Securities Ashiq Mubarack - Citi Asthika Goonewardene - Truist Securities Boris Peaker - Cowen Operator Good morning, and welcome to Mersana Therapeutics Fourth Quarter and Year End 2022 Co ...

Table of Contents UNITED STATES 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 001-38129 Mersana Therapeutics, Inc. 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. Indicate by check mark if the registrant is not required to file reports pursuant ...

Mersana Therapeutics, Inc. (NASDAQ:MRSN) Q3 2022 Earnings Conference Call November 7, 2022 8:30 AM ET Company Participants Jason Fredette - Senior Vice President, Investor Relations and Corporate Communications Anna Protopapas - President and Chief Executive Officer Arvin Yang - Senior Vice President and Chief Medical Officer Brian DeSchuytner - Senior Vice President and Chief Financial Office Conference Call Participants Jonathan Chang - SVB Securities Colleen Kusy - Baird Kaveri Pohlman - BTIG David Niere ...