Mersana Therapeutics Announces Closing of Public Offering of Common Stock and Full Exercise of Underwriters’ Option to Purchase Additional Shares

CAMBRIDGE, Mass., June 02, 2020 (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 the closing of its underwritten registered public offering of 9,200,000 shares of its common stock at the public offering price of $19.00 per share, which includes the exercise in full of the underwriters’ option to purchase additional shares of common stock. The total gross proceeds to Mersana from the offering, before deducting underwriting discounts and commissions and offering expenses, are approximately $174.8 million.
Cowen and SVB Leerink acted as joint bookrunning managers for the offering. Wedbush PacGrow acted as lead manager and Baird and H.C. Wainwright & Co. acted as co-managers for the offering.The shares of common stock described above were offered by Mersana pursuant to a shelf registration statement on Form S-3 (File No. 333-238140), as well as a related registration statement on Form S-3MEF filed with the Securities and Exchange Commission (SEC) pursuant to Rule 462(b) under the Securities Act of 1933, as amended. A preliminary prospectus supplement relating to and describing the terms of the offering was filed with the SEC on May 28, 2020. The final prospectus supplement relating to the offering was filed with the SEC on May 29, 2020 and copies of the final prospectus supplement and the accompanying prospectus may be obtained from: Cowen and Company, LLC, c/o Broadridge Financial Solutions, 1155 Long Island Avenue, Edgewood, New York 11717 Attention: Prospectus Department, by telephone at (833) 297-2926, or by email at PostSaleManualRequests@broadridge.com; or SVB Leerink LLC, Attention: Syndicate Department, One Federal Street, 37th Floor, Boston, Massachusetts 02110, by telephone at 800-808-7525, ext. 6132 or by email at syndicate@svbleerink.com. Electronic copies of the final prospectus supplement and the accompanying prospectus are also available on the website of the SEC at www.sec.gov.This press release shall not constitute an offer to sell, or the solicitation of an offer to buy, nor shall there be any sale of shares of these securities in any state or jurisdiction in which such offer, solicitation, or sale would be unlawful prior to registration or qualification under the securities laws of any such state or jurisdiction.About Mersana Therapeutics
Mersana Therapeutics is a clinical-stage biopharmaceutical company using its differentiated and proprietary ADC platforms to rapidly develop novel ADCs with optimal efficacy, safety and tolerability to meaningfully improve the lives of people fighting cancer. Mersana’s lead product candidate, XMT-1536, is in the expansion portion of a Phase 1 proof-of-concept clinical study in patients with ovarian cancer and NSCLC adenocarcinoma. XMT-1592, Mersana’s second ADC product candidate targeting NaPi2b-expressing tumors, was created using Mersana’s customizable and homogeneous Dolasynthen platform and is in the dose escalation portion of a Phase 1 proof-of-concept clinical study. The Company’s early stage programs include a B7-H4 targeting ADC, as well as a STING-agonist ADC developed using the Company’s Immunosynthen platform. In addition, multiple partners are using Mersana’s Dolaflexin platform to advance their ADC pipelines.Forward-Looking Statements
This press release 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 strategy and the design, progression and timing of its clinical trials. Forward-looking statements generally can be identified by terms such as “aims,” “anticipates,” “believes,” “contemplates,” “continues,” “could,” “estimates,” “expects,” “goal,” “intends,” “may,” “on track,” “plans,” “possible,” “potential,” “predicts,” “projects,” “seeks,” “should,” “target,” “will,” “would” or similar expressions and the negatives of those terms. Forward-looking statements represent management’s beliefs and assumptions only as of the date of this press release. The Company’s operations involve risks and uncertainties, many of which are outside its control, and any one of which, or combination of which, could materially affect its results of operations and whether the forward-looking statements ultimately prove to be correct.  Factors that may materially affect the Company’s results of operations and whether these forward-looking statements prove to be correct include, among other things, that preclinical testing may not be predictive of the results or success of ongoing or later preclinical or clinical trials, that the development and testing of the Company’s product candidates and new platforms will take longer and/or cost more than planned, and that the identification of new product candidates will take longer than planned, as well as those listed in the Company’s Annual Report on Form 10-K filed on February 28, 2020, with the Securities and Exchange Commission (“SEC”), the Company’s Quarterly Report on Form 10-Q filed on May 8, 2020 with the SEC and subsequent SEC filings. In addition, while we expect that the COVID-19 pandemic might adversely affect the Company’s preclinical and clinical development efforts, business operations and financial results, the extent of the impact on the Company’s operations and the value of and market for the Company’s common stock will depend on future developments that are highly uncertain and cannot be predicted with confidence at this time, such as the ultimate duration of the pandemic, travel restrictions, quarantines, physical distancing and business closure requirements in the U.S. and in other countries, and the effectiveness of actions taken globally to contain and treat the disease. Except as required by law, the Company assumes no obligation to update these forward-looking statements publicly, or to update the reasons actual results could differ materially from those anticipated in the forward-looking statements, even if new information becomes available in the future.Contact:Investor & Media Contact
Sarah Carmody, 617-844-8577
scarmody@mersana.com