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, 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 001-38129 Mersana Therapeutics, Inc. (Exact name of registrant as specified in its charter) (State or other jurisdiction of incorporation o ...

Accelerating ADC Innovation …because patients are waiting September 2022 Legal Disclaimer This presentation contains "forward-looking" statements and information within the meaning of the Private Securities Litigation Reform Act of 1995. These statements may be identified by words such as "aims," "anticipates," "believes," "could," "estimates," "expects," "forecasts," "goal," "intends," "may," "plans," "possible," "potential," "seeks," "will" and variations of these words or similar expressions, although no ...

Accelerating ADC Innovation …because patients are waiting August 2022 Legal Disclaimer This presentation contains "forward-looking" statements and information within the meaning of the Private Securities Litigation Reform Act of 1995. These statements may be identified by words such as "aims," "anticipates," "believes," "could," "estimates," "expects," "forecasts," "goal," "intends," "may," "plans," "possible," "potential," "seeks," "will" and variations of these words or similar expressions, although not a ...

Financial Data and Key Metrics Changes - Collaboration revenue for Q2 2022 was $4.3 million, compared to an immaterial amount in Q2 2021, reflecting revenue from the collaboration with Janssen [38] - Research and development expenses increased to $41.2 million in Q2 2022 from $32 million in Q2 2021, driven by clinical and manufacturing costs for XMT-1660 and UpRi [39] - General and administrative expenses rose to $14.8 million in Q2 2022 from $8.9 million in Q2 2021, primarily due to increased consulting fees and headcount [41] - Net loss for Q2 2022 was $52.2 million, or $0.55 per share, compared to a net loss of $40.9 million, or $0.59 per share in Q2 2021 [42] Business Line Data and Key Metrics Changes - The company is advancing three clinical trials: UPLIFT, UP-NEXT, and UPGRADE, focusing on UpRi as a foundational medicine in ovarian cancer [15][17] - XMT-1660 and XMT-2056 have recently cleared INDs, with XMT-1660 targeting B7-H4 and XMT-2056 targeting HER2 [18][30] Market Data and Key Metrics Changes - The collaboration with GSK provides an upfront option purchase fee of $100 million, extending the company's cash runway into the first half of 2024 [12][33] - If GSK exercises its option, the company could receive an additional $90 million and up to approximately $1.3 billion in milestone payments [34] Company Strategy and Development Direction - The company aims to be a leader in the ADC space, with a focus on advancing its Immunosynthen platform and establishing UpRi in ovarian cancer [7][14] - Strategic partnerships, such as the recent collaboration with GSK, are viewed as essential for leveraging the company's platforms and enhancing financial resources [8][36] Management's Comments on Operating Environment and Future Outlook - Management expressed confidence in the progress made in clinical trials and the potential for transformative developments in 2023 [19][43] - The company acknowledges the high unmet medical needs in ovarian cancer treatment and aims to address these through its ongoing trials [22] Other Important Information - The company ended the quarter with approximately $225 million in cash and marketable securities, with additional access to $35 million in low-cost capital [36] - The company is actively diversifying its clinical pipeline while maintaining a strong focus on its ADC platforms [18][30] Q&A Session Summary Question: Are you still running the Phase 1 study for XMT-2056? - Yes, the Phase 1 study is ongoing and remains wholly owned by the company, focusing on breast cancer [47] Question: Any additional color on the timelines for the option exercise with GSK? - It is too early to provide specific timelines for the option exercise [49] Question: Was there any new data shared with GSK during the diligence process for 2056? - The diligence process was comprehensive, involving both public and additional data to support the potential of 2056 [54] Question: How many patients and what follow-up can be expected for UPGRADE data in Q4? - Initial interim data will focus on safety and tolerability, with further efficacy characterized in the expansion data [55]

Accelerating ADC Innovation …because patients are waiting August 2022 Legal Disclaimer This presentation contains "forward-looking" statements and information within the meaning of the Private Securities Litigation Reform Act of 1995. These statements may be identified by words such as "aims," "anticipates," "believes," "could," "estimates," "expects," "forecasts," "goal," "intends," "may," "plans," "possible," "potential," "seeks," "will" and variations of these words or similar expressions, although not a ...

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, 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 001-38129 Mersana Therapeutics, Inc. (Exact name of registrant as specified in its charter) (State or other jurisdiction of incorporation or org ...

Accelerating ADC Innovation …because patients are waiting June 2022 Legal Disclaimer This presentation contains "forward-looking" statements and information within the meaning of the Private Securities Litigation Reform Act of 1995. These statements may be identified by words such as "aims," "anticipates," "believes," "could," "estimates," "expects," "forecasts," "goal," "intends," "may," "plans," "possible," "potential," "seeks," "will" and variations of these words or similar expressions, although not all ...

Mersana Therapeutics, Inc. (NASDAQ:MRSN) Q1 2022 Earnings Conference Call May 9, 2022 8:00 AM ET Company Participants Jason Fredette - Senior Vice President, Investor Relations and Corporate Communications Anna Protopapas - President, CEO & Director Arvin Yang - Senior VP & Chief Medical Officer Tim Lowinger - Chief Science & Technology Officer Brian DeSchuytner - Senior VP & CFO Conference Call Participants Jonathan Chang - SVB Leerink Boris Peaker - Cowen Daniel Wolle - JPMorgan Colleen Kusy - Baird David ...

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, 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 001-38129 Mersana Therapeutics, Inc. (Exact name of registrant as specified in its charter) (State or other jurisdiction of incorporation or or ...

Accelerating ADC Innovation …because patients are waiting February 2022 Legal Disclaimer This presentation contains "forward-looking" statements within the meaning of federal securities laws. These forward-looking statements are not statements of historical facts and are based on management's beliefs and assumptions and on information currently available to management. Forward-looking statements include information concerning Mersana Therapeutics, Inc.'s (the "Company's") business strategy and the design, p ...