Mersana Presents New Data on Investigational Cancer Antibody Drug Conjugate at American Association of Cancer Research Annual Meeting

March 2, 2017

Poster Presentations Detail Advances in Company’s Lead Oncology ADC Compound, XMT-1522

CAMBRIDGE, Mass., March 2, 2017 -- Mersana Therapeutics, Inc., a biotechnology company focused on discovering and developing a pipeline of antibody drug conjugates (ADCs) based on its  Fleximer® platform technology, today announced that it will present data on its lead preclinical immunoconjugate, XMT-1522, at the American Association of Cancer Research (AACR) Annual Meeting 2017 in Washington, D.C. The two poster presentations will highlight results from ongoing non-clinical studies where the compound was evaluated as a potential combination partner with immunomodulatory cancer therapies and it was also characterized for its pharmacokinetics, metabolism and biodistribution in tumor-bearing mice.

The accepted abstracts are listed below and are now available online on the AACR 2017 conference website: www.aacr.org

Abstract Control Number: 6879
Title: Combination of anti-HER2 ADC XMT-1522 and checkpoint inhibitor pembrolizumab for treatment of NSCLC in preclinical models 
Authors: Natasha Bodyak, Marina Protopopova, Qingxiu Zhang, Alex Yurkovetskiy, Mao Yin, LiuLiang Qin, Laura L Poling, Rebecca Mosher, Donald A. Bergstrom, Timothy B. Lowinger

Session Category: Immunology
Session Title: Immune Response to Hematopoietic Tumors: New Developments in Tumor Immunology
Session Date and Time: Monday Apr 3, 2017 1:00 PM - 5:00 PM
Location: Convention Center, Halls A-C, Poster Section 26
Poster Board Number: 29

Abstract control number: 6716
Title: Non-clinical pharmacokinetics of XMT-1522, a HER2 targeting auristatin-based antibody drug conjugate.
Authors: Donald A. Bergstrom, Natalya Bodyak, Alex Yurkovetskiy, Michael DeVit, Mao Yin, Laura L. Poling, Joshua D. Thomas, Dmitry Gumerov, Dongmei Xiao, Elena Ter-Ovanesyan, Charlie Bu, LiuLiang Qin, Alex Uttard, Alex Johnson, Timothy B. Lowinger
Session Category: Experimental and Molecular Therapeutics
Session Date and Time: Sunday Apr 2, 2017 1:00 PM - 5:00 PM
Location: Convention Center, Halls A-C, Poster Section 26
Poster Board Number: 29

About XMT-1522

XMT-1522 incorporates a novel, proprietary HER2 antibody, which is conjugated with Mersana’s Dolaflexin platform which includes its Fleximer technology and proprietary auristatin payload. XMT-1522 provides a drug load of approximately 12-15 molecules per antibody, specifically designed to improve potency while simultaneously increasing tolerability. XMT-1522 has the potential to extend HER2-targeted therapy beyond the current “HER2-positive” populations into patients with lower levels of HER2 expression.

About Mersana Therapeutics

Mersana Therapeutics is a biotechnology company with highly differentiated and proprietary immunoconjugate platforms that allow for significantly higher drug loads, providing greater efficacy while simultaneously increasing tolerability. As a result, our platforms provide for expanded opportunities to provide meaningful clinical benefit to patients.  Our lead program, XMT1522, is in Phase I clinical trials. Our second program, XMT1536, will be entering clinical trials in the latter part of 2017.  In addition, our partners are advancing their pipeline of immunoconjugates using our platforms. 

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