About Mersana Therapeutics CAMBRIDGE, Mass., May 22, 2024 (GLOBE NEWSWIRE) -- 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 announced that members of management will present at the following upcoming investor conferences: Live webcasts of these events will be available on the Investors & Media section of Mersana's website at w ...

Mersana Therapeutics, Inc. (NASDAQ:MRSN) Q1 2024 Earnings Conference Call May 9, 2024 8:00 AM ET Company Participants Jason Fredette - Senior Vice President, Investor Relations & Corporate Communications Martin Huber - President & Chief Executive Officer Brian DeSchuytner - Chief Financial Officer & Chief Operating Officer Conference Call Participants Tara Bancroft - TD Cowen Kaveri Pohlman - BTIG Dylan Drakes - Leerink Partners Brian Cheng - JPMorgan Michael Schmidt - Guggenheim Asthika Goonewardene - Trui ...

Mersana Therapeutics, Inc. (MRSN) came out with a quarterly loss of $0.16 per share versus the Zacks Consensus Estimate of a loss of $0.18. This compares to loss of $0.52 per share a year ago. These figures are adjusted for non-recurring items.This quarterly report represents an earnings surprise of 11.11%. A quarter ago, it was expected that this company would post a loss of $0.20 per share when it actually produced a loss of $0.16, delivering a surprise of 20%.Over the last four quarters, the company has ...

Financial Performance - For the three months ended March 31, 2024, the company's net loss was $19.3 million, a decrease from $56.2 million for the same period in 2023[141] - As of March 31, 2024, the company had an accumulated deficit of $845.7 million[141] - Net loss improved by $36.9 million, from a loss of $56.2 million in Q1 2023 to a loss of $19.3 million in Q1 2024[160] - Total other income, net was consistent at $1.7 million in Q1 2024 compared to $1.6 million in Q1 2023[167] Research and Development - Total research and development costs for the three months ended March 31, 2024, were $18.7 million, down from $47.3 million in the same period of 2023[151] - External costs for the XMT-1660 program were $2.9 million for the three months ended March 31, 2024, compared to $3.5 million in 2023[151] - The company expects to incur significant research and development expenses over the next several years as it continues clinical development and manufacturing activities[155] - Research and development expenses decreased by $28.6 million, from $47.3 million in Q1 2023 to $18.7 million in Q1 2024[162] Collaboration and Revenue - The company recognized $3.2 million in collaboration revenue related to the Merck KGaA Agreement for the three months ended March 31, 2024, compared to $3.1 million in 2023[142] - Collaboration revenue increased by $1.4 million, from $7.8 million in Q1 2023 to $9.2 million in Q1 2024, primarily due to a $4.6 million increase from the Johnson & Johnson Agreement[161] - The company has entered into a global collaboration with GSK for the co-development and commercialization of XMT-2056[139] Clinical Trials - The Phase 1 clinical trial for XMT-1660 is currently enrolling patients, with initial data expected to be disclosed in the second half of 2024[136] - The FDA clinical hold on the Phase 1 trial of XMT-2056 was resolved in Q4 2023, and the trial is actively recruiting patients[136] Operational Changes - The company has discontinued the development of XMT-1536 and reduced its employee base by approximately 50% as part of a restructuring effort[138] - The company expects to incur significant general and administrative expenses over the next several years to support ongoing research and development activities[157] Cash Flow and Financial Position - Cash, cash equivalents, and marketable securities totaled $183.1 million as of March 31, 2024[173] - Net cash used in operating activities was $32.7 million in Q1 2024, compared to $29.0 million in Q1 2023[176] - Net cash used in investing activities was $72.5 million in Q1 2024, compared to net cash provided of $1.4 million in Q1 2023[177] - Net cash provided by financing activities was $5.8 million in Q1 2024, down from $21.5 million in Q1 2023[178] - As of March 31, 2024, the company had cash, cash equivalents, and marketable securities totaling $183.1 million[186] - The company had $25.0 million outstanding under the New Credit Facility as of March 31, 2024[187] - The interest rate on the New Credit Facility is a floating rate, with a minimum of 8.50% or the prime rate plus 5.25%[187] Compliance and Controls - There were no material changes to the company's contractual obligations during the three months ended March 31, 2024[184] - The company reported no material changes to its critical accounting estimates during the same period[185] - The company is not currently exposed to market risk related to foreign currency exchange rates as of March 31, 2024[188] - The company's disclosure controls and procedures were evaluated as effective at the reasonable assurance level as of March 31, 2024[190] - There were no changes in the internal control over financial reporting that materially affected the company during the quarter ended March 31, 2024[191] - The company is not currently party to any material legal proceedings[193]

May 9, 2024 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 trial ...

Exhibit 99.1 Mersana Therapeutics Provides Business Update and Announces First Quarter 2024 Financial Results CAMBRIDGE, Mass., May 9, 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 first quarter ended March 31, 2024. "In recent months, we presented new p ...

CAMBRIDGE, Mass., May 03, 2024 (GLOBE NEWSWIRE) -- 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 announced that on May 1, 2024, an authorized sub-committee of the Board of Directors of Mersana granted an inducement award, consisting of a restricted stock unit (RSU) award to acquire 35,100 shares of its common stock, to one new ...

CAMBRIDGE, Mass., May 02, 2024 (GLOBE NEWSWIRE) -- 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 announced that it will provide business updates and report its financial results for the first quarter ended March 31, 2024 on Thursday, May 9, 2024. The company will host a conference call and webcast at 8:00 a.m. Eastern Time tha ...

Financial Data and Key Metrics - Collaboration revenue for Q4 2023 was $10.7 million, down from $14.7 million in Q4 2022, primarily due to the timing of research activities and the achievement of an early development milestone with Johnson & Johnson in Q4 2022 [10] - General and administrative expenses for Q4 2023 were $10.1 million, compared to $14.8 million in Q4 2022, with $1.9 million in non-cash stock-based compensation expenses included [11] - Research and development expenses for Q4 2023 were $21.5 million, down from $45.7 million in Q4 2022, driven by reduced manufacturing and clinical costs related to UpRi and XMT-2056, and lower employee compensation costs [99] - Net loss for Q4 2023 was $19.5 million, compared to a net loss of $44.9 million in Q4 2022 [100] - The company ended Q4 2023 with approximately $209 million in cash, cash equivalents, and marketable securities, with net cash used in operating activities at $32 million, down significantly from prior quarters due to restructuring and UpRi wind-down efforts [98] Business Line Data and Key Metrics - The company is advancing its Dolasynthen ADC platform, with XMT-1660 (B7-H4 targeting ADC) in Phase 1 trials, currently at a dose of 59 mg/m², the highest dose investigated clinically with Dolasynthen ADC [6][81] - XMT-2056, the lead Immunosynthen ADC targeting HER2, is in the process of restarting its Phase 1 trial after a clinical hold by the FDA in Q4 2023 [70] - The company has collaboration agreements with Johnson & Johnson, Merck KGaA, and GSK, focusing on maximizing the potential of its ADC platforms and product candidates [8] Market Data and Key Metrics - The company is targeting solid tumors, including triple-negative breast cancer, estrogen receptor-positive breast cancer, ovarian cancer, and endometrial cancer, with XMT-1660 [68] - For XMT-2056, the company plans to enroll patients with HER2-positive tumors, including breast, gastric, colorectal, and non-small cell lung cancer [70] Company Strategy and Industry Competition - The company aims to minimize dose-limiting platform toxicities, avoid resistance mechanisms, and extend ADC therapies beyond cytotoxics to include targeted innate immune responses [3][4] - The Dolasynthen platform is designed to avoid dose-limiting neutropenia and peripheral neuropathy associated with other ADC platforms, such as vcMMAE [57][66] - The company believes its Immunosynthen platform, which harnesses STING, could be the next significant frontier for ADCs, offering potential for combination therapies with other standard-of-care treatments [7][113] Management Commentary on Operating Environment and Future Outlook - The company is optimistic about its differentiated ADC platforms and upcoming data readouts, particularly for XMT-1660, and believes its cash runway will support operations into 2026 [97][72] - Management highlighted the urgent unmet need for new ADCs with alternative payloads, as resistance to TOPO1-ADC treatments is emerging in breast cancer patients [69] Other Important Information - The company will present clinical data for discontinued candidates UpRi and XMT-1592 at the European Society of Gynecological Oncology (ESGO) conference, with 31 patients in the XMT-1592 dataset [5][114] - The company is exploring alternative dosing schedules for XMT-1660, including Q3 and Q4 schedules, to optimize dosing [81] Q&A Session Summary Question: Decision-making process behind the second-gen NaPi2b program and lessons for B7-H4 program [15] - The decision to reprioritize XMT-1592 was driven by the lower prevalence of the NaPi2b biomarker in lung cancer compared to ovarian cancer, as well as cost considerations [79][16] - For B7-H4, the company has not observed pneumonitis, which was associated with NaPi2b, and is continuing to optimize dosing and enrollment [80][81] Question: Enrollment progress and dose optimization for B7-H4 study [15] - The company has escalated to a dose of 59 mg/m² for XMT-1660 and is continuing to enroll patients in backfill cohorts to optimize dosing [81] Question: Expectations for midyear 1660 update and takeaways from 1592 data [101] - The midyear update for XMT-1660 will include efficacy and safety data, with the company highlighting the absence of peripheral neuropathy, neutropenia, and ocular toxicity observed in XMT-1592 [13][14] Question: Cash runway and expense trajectory [54] - The company expects its cash runway to support operations into 2026, with reduced OpEx in Q4 2023 and the completion of UpRi wind-down efforts [34][72] Question: B7-H4 biomarker and potential biomarker data in midyear update [41] - The company is measuring B7-H4 at baseline but not preselecting patients based on it, and has not decided whether to share biomarker data in the midyear update [128] Question: Differentiation and positioning of XMT-1660 compared to peers [133] - The company believes its Dolasynthen platform offers advantages in terms of lower toxicity and potential for combination therapies, with a focus on triple-negative breast cancer and other solid tumors [123][135] Question: Restarting the XMT-2056 trial and GSK's involvement [111] - The company is in the process of restarting the XMT-2056 trial, with GSK engaged but not having exercised its option, leaving decision-making control with the company [86][109] Question: Duration of response and resistance mechanisms in breast cancer [30][52] - The company is cautious about interpreting duration of response in Phase 1 data but notes that patients who responded to UpRi had a duration of response over seven months [31][137] - The company is enrolling patients who have received prior TOPO ADCs to assess resistance mechanisms and the efficacy of XMT-1660 [60][52]

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 001-38129 Mersana Therapeutics, Inc. (Exact name of registrant as specified in its charter) Delaware 04-3562403 (State ...