CAMBRIDGE, Mass., October 13, 2016 -- Mersana Therapeutics, Inc., a biotechnology company focused on discovering and developing a pipeline of antibody drug conjugates (ADCs) based on its proprietary Dolaflexin® technology, today announced that the company has received the award of “Best ADC Platform Technology” for its Dolaflexin platform at the World ADC Conference. The award was presented at this annual conference as part of the World ADC Awards program which recognizes company and scientific leadership and innovation within antibody drug conjugate research. Mersana was also selected as a runner-up in the “New Drug Developer” category.

The “Best ADC Platform Technology” award, acknowledges the best linker or payload platform technology and is selected for the system’s novelty and originality as well as scientific and commercial validation of the platform. The “New Drug Developer” class, recognizes an emerging company within the ADC field that has made significant progress within its preclinical pipeline (at least one pipeline drug).

Mersana’s lead platform, Dolaflexin, is based on the company’s Fleximer polymer backbone and a proprietary aurastatin payload. Fleximer allows for significantly higher payload per antibody (>15) than other ADC approaches resulting in higher efficacy .Dolaflexin’s novel, proprietary auristatin payload is designed to be highly potent when released in the tumor cell but to subsequently be metabolized into less potent agent hence resulting in improved tolerability .Dolaflexin based ADCs have been shown in pre-clinical studies to be highly efficacious while maintaining a wider therapeutic index than traditional ADCs approaches.

“Receiving this award underscores the scientific innovation of Mersana’s Discovery team and potential of our Dolaflexin platform,” said Anna Protopapas, President and Chief Executive Officer of Mersana. “We are grateful to the Conference for this recognition and will continue to commit ourselves to developing novel cancer treatments to address ongoing patient needs.”

Using its Dolaflexin platform, Mersana has rapidly developed a burgeoning oncology pipeline that includes two compounds that are advancing towards clinical studies. XMT-1522, Mersana’s first pipeline product, defines a new class of HER2-targeted therapies. XMT-1522 is armed with about 15 auristatin molecules per antibody, making it highly potent in tumor models that express relatively low amounts of the HER2 protein. XMT-1522 has the potential to extend HER2-targeted therapy beyond the current “HER2-positive” population into patients with lower levels of HER2 expression. XMT-1536 is a highly potent anti-sodium-dependent phosphate transport protein 2B (anti-NaPi2b) immunoconjugate comprised of an average of 15 auristatin molecules conjugated to XMT-1535, a novel humanized anti-NaPi2b antibody. Recently, at AACR 2016, data were presented that demonstrated significant anti-cancer activity in non-small cell lung cancer (NSCLC) and ovarian cancer tumor models.

About ADC Awards
Now in their third year, the World ADC Awards showcase excellence within antibody drug conjugate research. The World ADC Awards reward the innovation, leadership, and devotion shown by the best companies, teams, and individuals in the industry. Across eight categories the Awards will recognize the extraordinary endeavours, teamwork and commercial acumen that has propelled the field to the forefront of cancer research today.

About Mersana Therapeutics
Mersana Therapeutics is advancing a proprietary pipeline of targeted oncology therapeutics leveraging its game-changing Fleximer® immunoconjugate technology. Mersana's product candidates XMT-1522 and XMT-1536 have the potential to address significant unmet needs and improve patient outcomes in multiple oncology indications. Fleximer-based immunoconjugate molecules have been shown to have superior efficacy, including with targets previously considered not amenable to antibody-drug conjugate approaches. Mersana has collaborations utilizing Fleximer technology with Takeda, Merck KGaA, and Asana BioSciences. For more information, please visit www.mersana.com.

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