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, 2019. 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 Jurisdicti ...

THERAPEUTICS Accelerating ADC Innovation …because patients are waiting 38th Annual JP Morgan Healthcare Conference January 16, 2020 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 the Company's business ...

Mersana Therapeutics, Inc. (NASDAQ:MRSN) Q3 2019 Earnings Conference Call November 6, 2019 8:00 AM ET Company Participants Sarah Carmody - Executive Director, IR & Corporate Communications Anna Protopapas - President, CEO & Director Dirk Huebner - Chief Medical Officer Timothy Lowinger - Chief Science & Technology Officer Brian DeSchuytner - SVP, Finance & Product Strategy Conference Call Participants Jonathan Chang - SVB Leerink Earl DeSouza - H.C. Wainwright & Co. Boris Peaker - Cowen and Company Daniel W ...

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, 2019 Table of Contents UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 OR ☐ TRANSITION REPORT PURSUANT TO SECTION 13 OR 15(d) OF THE SECURITIES EXCHANGE ACT OF 1934 Commission file number 001-38129 Mersana Therapeutics, Inc. (Exact name of registrant as specified in its charter) (State or other jurisdiction of (I.R.S. Employer incorporation ...

Table of Contents UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 FORM 10-Q ☒ QUARTERLY REPORT PURSUANT TO SECTION 13 OR 15(d) OF THE SECURITIES EXCHANGE ACT OF 1934 For the quarterly period ended June 30, 2019 OR ☐ TRANSITION REPORT PURSUANT TO SECTION 13 OR 15(d) OF THE SECURITIES EXCHANGE ACT OF 1934 Commission file number 001-38129 Mersana Therapeutics, Inc. (Exact name of registrant as specified in its charter) (State or other jurisdiction of (I.R.S. Employer incorporation or or ...

Table of Contents UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 FORM 10‑Q ☒ QUARTERLY REPORT PURSUANT TO SECTION 13 OR 15(d) OF THE SECURITIES EXCHANGE ACT OF 1934 For the quarterly period ended March 31, 2019 OR ☐ TRANSITION REPORT PURSUANT TO SECTION 13 OR 15(d) OF THE SECURITIES EXCHANGE ACT OF 1934 Commission file number 001-38129 Mersana Therapeutics, Inc. (Exact name of registrant as specified in its charter) (State or other jurisdiction of (I.R.S. Employer incorporation or o ...

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, 2018. 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) Delaware 04-3562403 (State ...