<SEC-DOCUMENT>0001104659-25-077187.txt : 20250813
<SEC-HEADER>0001104659-25-077187.hdr.sgml : 20250813
<ACCEPTANCE-DATETIME>20250813071333
ACCESSION NUMBER:		0001104659-25-077187
CONFORMED SUBMISSION TYPE:	8-K
PUBLIC DOCUMENT COUNT:		13
CONFORMED PERIOD OF REPORT:	20250813
ITEM INFORMATION:		Results of Operations and Financial Condition
ITEM INFORMATION:		Financial Statements and Exhibits
FILED AS OF DATE:		20250813
DATE AS OF CHANGE:		20250813

FILER:

	COMPANY DATA:	
		COMPANY CONFORMED NAME:			Mersana Therapeutics, Inc.
		CENTRAL INDEX KEY:			0001442836
		STANDARD INDUSTRIAL CLASSIFICATION:	PHARMACEUTICAL PREPARATIONS [2834]
		ORGANIZATION NAME:           	03 Life Sciences
		EIN:				000000000
		STATE OF INCORPORATION:			DE
		FISCAL YEAR END:			1231

	FILING VALUES:
		FORM TYPE:		8-K
		SEC ACT:		1934 Act
		SEC FILE NUMBER:	001-38129
		FILM NUMBER:		251208976

	BUSINESS ADDRESS:	
		STREET 1:		840 MEMORIAL DRIVE
		CITY:			CAMBRIDGE
		STATE:			MA
		ZIP:			02139
		BUSINESS PHONE:		617-498-0020

	MAIL ADDRESS:	
		STREET 1:		840 MEMORIAL DRIVE
		CITY:			CAMBRIDGE
		STATE:			MA
		ZIP:			02139

	FORMER COMPANY:	
		FORMER CONFORMED NAME:	MERSANA THERAPEUTICS INC
		DATE OF NAME CHANGE:	20080813
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<p style="margin: 0; font-size: 10pt"><span style="font: 10pt Times New Roman, Times, Serif">&#160;</span></p>

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<p style="font: 18pt Times New Roman, Times, Serif; margin: 0pt 0; text-align: center"><b>UNITED STATES</b></p>

<p style="font: 18pt Times New Roman, Times, Serif; margin: 0pt 0; text-align: center"><b>SECURITIES AND EXCHANGE COMMISSION</b></p>

<p style="font: 10pt Times New Roman, Times, Serif; margin: 0pt 0; text-align: center"><b>Washington, D.C. 20549</b></p>

<p style="font: 10pt Times New Roman, Times, Serif; margin: 0pt 0; text-align: center">&#160;</p>

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<p style="font: 10pt Times New Roman, Times, Serif; margin: 0pt 0; text-align: center">&#160;</p>

<p style="font: 10pt Times New Roman, Times, Serif; margin: 0pt 0; text-align: center"><b>CURRENT REPORT</b></p>

<p style="font: 10pt Times New Roman, Times, Serif; margin: 0pt 0; text-align: center"><b>Pursuant to Section 13 or 15(d) <br/>
of the
Securities Exchange Act of 1934</b></p>

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<p style="font: 10pt Times New Roman, Times, Serif; margin: 0pt 0; text-align: center">Date of Report (Date of earliest event
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<p style="font: 10pt Times New Roman, Times, Serif; margin: 0pt 0; text-align: center">&#160;</p>

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<p style="font: 10pt Times New Roman, Times, Serif; margin: 0pt 0; text-align: center"><b>(Exact name of registrant as specified in its
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<td style="vertical-align: top; text-align: center"><b>(State or other jurisdiction <br/>
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<p style="font: 10pt Times New Roman, Times, Serif; margin-top: 0pt; margin-bottom: 0pt; text-align: center">Registrant&#8217;s telephone number, including
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<p style="font: 10pt Times New Roman, Times, Serif; margin: 0pt 0; text-align: center">&#160;</p>

<p style="font: 10pt Times New Roman, Times, Serif; margin: 0pt 0; text-align: center"><b>Not Applicable</b></p>

<p style="font: 10pt Times New Roman, Times, Serif; margin: 0pt 0; text-align: center">(Former name or former address, if changed since
last report)</p>

<p style="font: 10pt Times New Roman, Times, Serif; margin: 0pt 0; text-align: center">&#160;</p>

<p style="font: 10pt Times New Roman, Times, Serif; margin-top: 0pt; margin-right: 0; margin-bottom: 0pt; text-align: justify">Check the appropriate box below if the Form 8-K filing is intended
to simultaneously satisfy the filing obligation of the registrant under any of the following provisions (<span style="text-decoration: underline">see</span> General Instruction A.2. below):</p>

<p style="font: 10pt Times New Roman, Times, Serif; margin: 0pt 0">&#160;</p>

<p style="font: 10pt Times New Roman, Times, Serif; margin: 0pt 0 0pt 0.25in; text-align: left; text-indent: -0.25in"><span id="xdx_904_edei--WrittenCommunications_c20250813__20250813_zCJs5xgO7BZ2" style="font-family: Wingdings"><ix:nonNumeric contextRef="AsOf2025-08-13" format="ixt:booleanfalse" id="Fact000021" name="dei:WrittenCommunications">&#168;</ix:nonNumeric></span><span style="font-family: Times New Roman, Times, Serif">&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;Written
communications pursuant to Rule 425 under the Securities Act (17 CFR 230.425)</span></p>

<p style="font: 10pt Times New Roman, Times, Serif; margin: 0pt 0 0pt 0.25in; text-indent: -0.25in"><span style="font-size: 1pt">&#160;</span></p>

<p style="font: 10pt Times New Roman, Times, Serif; margin: 0pt 0 0pt 0.25in; text-align: left; text-indent: -0.25in"><span id="xdx_901_edei--SolicitingMaterial_c20250813__20250813_zHux9waVexFh" style="font-family: Wingdings"><ix:nonNumeric contextRef="AsOf2025-08-13" format="ixt:booleanfalse" id="Fact000022" name="dei:SolicitingMaterial">&#168;</ix:nonNumeric></span><span style="font-family: Times New Roman, Times, Serif">&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;Soliciting
material pursuant to Rule 14a-12 under the Exchange Act (17 CFR 240.14a-12)</span></p>

<p style="font: 10pt Times New Roman, Times, Serif; margin: 0pt 0 0pt 0.25in; text-indent: -0.25in"><span style="font-size: 1pt">&#160;</span></p>

<p style="font: 10pt Times New Roman, Times, Serif; margin: 0pt 0 0pt 0.25in; text-align: left; text-indent: -0.25in"><span id="xdx_90B_edei--PreCommencementTenderOffer_c20250813__20250813_z5mdNIujSXHi" style="font-family: Wingdings"><ix:nonNumeric contextRef="AsOf2025-08-13" format="ixt:booleanfalse" id="Fact000023" name="dei:PreCommencementTenderOffer">&#168;</ix:nonNumeric></span><span style="font-family: Times New Roman, Times, Serif">&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;Pre-commencement
communications pursuant to Rule 14d-2(b) under the Exchange Act (17 CFR 240.14d-2(b))</span></p>

<p style="font: 10pt Times New Roman, Times, Serif; margin: 0pt 0 0pt 0.25in; text-indent: -0.25in"><span style="font-size: 1pt">&#160;</span></p>

<p style="font: 10pt Times New Roman, Times, Serif; margin: 0pt 0 0pt 0.25in; text-align: left; text-indent: -0.25in"><span style="font-family: Wingdings"><span id="xdx_90D_edei--PreCommencementIssuerTenderOffer_c20250813__20250813_zlP0bWr9MEk2"><ix:nonNumeric contextRef="AsOf2025-08-13" format="ixt:booleanfalse" id="Fact000024" name="dei:PreCommencementIssuerTenderOffer">&#168;</ix:nonNumeric></span></span><span style="font-family: Times New Roman, Times, Serif">&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;Pre-commencement
communications pursuant to Rule 13e-4(c) under the Exchange Act (17 CFR 240.13e-4(c))</span></p>

<p style="font: 10pt Times New Roman, Times, Serif; margin: 0pt 0">&#160;</p>

<p style="font: 10pt Times New Roman, Times, Serif; margin: 0pt 0; color: #221E1F">Securities registered pursuant to Section 12(b)
of the Act:</p>

<p style="font: 10pt Times New Roman, Times, Serif; margin: 0pt 0; color: #221E1F">&#160;</p>

<table cellspacing="0" cellpadding="0" style="font: 10pt Times New Roman, Times, Serif; width: 100%; border-collapse: collapse">
<tr style="text-align: center; vertical-align: bottom">
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<p style="font: 10pt Times New Roman, Times, Serif; margin: 0pt 0">&#160;</p>

<p style="font: 10pt Times New Roman, Times, Serif; text-align: justify; margin-top: 0pt; margin-right: 0; margin-bottom: 0pt">Indicate by check mark whether the registrant is an emerging growth
company as defined in Rule 405 of the Securities Act of 1933 (&#167;230.405 of this chapter) or Rule 12b-2 of the Securities Exchange
Act of 1934 (&#167;240.12b-2 of this chapter).</p>

<p style="font: 10pt Times New Roman, Times, Serif; margin: 0pt 0">&#160;</p>

<p style="font: 10pt Times New Roman, Times, Serif; text-align: left; margin-top: 0pt; margin-right: 0; margin-bottom: 0pt"><span style="font-family: Times New Roman, Times, Serif">Emerging growth company </span><span style="font-family: Wingdings"><span id="xdx_902_edei--EntityEmergingGrowthCompany_c20250813__20250813_z12Np4yoPQuk"><ix:nonNumeric contextRef="AsOf2025-08-13" format="ixt:booleanfalse" id="Fact000028" name="dei:EntityEmergingGrowthCompany">&#168;</ix:nonNumeric></span></span></p>

<p style="font: 10pt Times New Roman, Times, Serif; margin: 0pt 0">&#160;</p>

<p style="font: 10pt Times New Roman, Times, Serif; text-align: justify; margin-top: 0pt; margin-right: 0; margin-bottom: 0pt"><span style="font-family: Times New Roman, Times, Serif">If an emerging
growth company, indicate by check mark if the registrant has elected not to use the extended transition period for complying with any
new or revised financial accounting standards provided pursuant to Section 13(a) of the Exchange Act. <span style="font-family: Wingdings">&#168;</span><span style="font-family: Wingdings"></span></span></p>

<p style="font: 10pt Times New Roman, Times, Serif; margin: 0pt 0">&#160;</p>

<p style="font: 10pt Times New Roman, Times, Serif; margin: 0pt 0"></p>

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<p style="font: 10pt Times New Roman, Times, Serif; margin: 0pt 0">&#160;</p>

<p style="font: 10pt Times New Roman, Times, Serif; margin: 0pt 0"></p>

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<p style="font: 10pt Times New Roman, Times, Serif; margin: 0pt 0">&#160;</p>

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<td style="width: 1in"><b>Item 2.02</b></td><td style="text-align: justify"><b>Results of Operations and Financial Condition.&#160;</b></td></tr></table>

<p style="font: 10pt Times New Roman, Times, Serif; margin: 0pt 0; text-align: justify; background-color: white"><b>&#160;</b></p>

<p style="font: 10pt Times New Roman, Times, Serif; margin: 0pt 0; text-align: justify; background-color: white">On August 13, 2025, Mersana
Therapeutics, Inc. (the &#8220;Company&#8221;) issued a press release announcing business updates and financial results for the fiscal
quarter ended June 30, 2025.</p>

<p style="font: 10pt Times New Roman, Times, Serif; margin: 0pt 0; text-align: justify; text-indent: 0.5in; background-color: white">&#160;</p>

<p style="font: 10pt Times New Roman, Times, Serif; margin: 0pt 0; text-align: justify; background-color: white">The information furnished
in this Item 2.02, including Exhibit 99.1, shall not be deemed &#8220;filed&#8221; for purposes of Section 18 of the Securities Exchange
Act of 1934, as amended (the &#8220;Exchange Act&#8221;), or otherwise subject to the liabilities of that section, nor shall such information
be deemed incorporated by reference in any filing by the Company with the Securities and Exchange Commission (the &#8220;SEC&#8221;) under
the Securities Act of 1933, as amended (the &#8220;Securities Act&#8221;), or the Exchange Act, regardless of any general incorporation
language contained in such filing, except as expressly set forth by specific reference in such a filing.</p>

<p style="font: 10pt Times New Roman, Times, Serif; margin: 0pt 0"><b>&#160;</b></p>

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<td style="width: 1in"><b>Item&#160;9.01.</b></td><td><b>Financial Statements and Exhibits.</b></td></tr></table>

<p style="font: 10pt Times New Roman, Times, Serif; margin-top: 0pt; margin-bottom: 0pt">&#160;</p>

<p style="font: 10pt Times New Roman, Times, Serif; margin: 0pt 0">(d)&#160;Exhibits</p>

<p style="font: 10pt Times New Roman, Times, Serif; margin: 0pt 0">&#160;</p>

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    <td style="width: 0.25in">&#160;</td>
    <td style="border-bottom: black 1pt solid"><span style="font-family: Times New Roman, Times, Serif; font-size: 10pt"><b>Description</b></span></td></tr>
  <tr style="vertical-align: bottom">
    <td><a href="tm2523277d1_ex99-1.htm"><span style="font-family: Times New Roman, Times, Serif; font-size: 10pt">99.1</span></a></td>
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    <td><a href="tm2523277d1_ex99-1.htm"><span style="font-family: Times New Roman, Times, Serif; font-size: 10pt">Press Release issued by the Company on August 13, 2025.</span></a></td></tr>
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    <td><span style="font-family: Times New Roman, Times, Serif; font-size: 10pt">Cover Page Interactive Data File (embedded within the Inline XBRL document).</span></td></tr>
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<p style="font: 10pt Times New Roman, Times, Serif; margin: 0pt 0">&#160;</p>

<p style="font: 10pt Times New Roman, Times, Serif; margin: 0pt 0"></p>

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<p style="font: 10pt Times New Roman, Times, Serif; margin: 0pt 0">&#160;</p>

<p style="font: 10pt Times New Roman, Times, Serif; margin: 0pt 0; text-align: center"><b>SIGNATURES</b></p>

<p style="font: 10pt Times New Roman, Times, Serif; margin: 0pt 0">&#160;</p>

<p style="font: 10pt Times New Roman, Times, Serif; text-align: justify; margin: 0pt 0">Pursuant to the requirements of the Securities Exchange Act of 1934,
the registrant has duly caused this report to be signed on its behalf by the undersigned hereunto duly authorized.</p>

<p style="font: 10pt Times New Roman, Times, Serif; margin: 0pt 0; text-align: center">&#160;</p>

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  <tr style="vertical-align: bottom">
    <td style="width: 50%">&#160;</td>
    <td style="width: 3%">&#160;</td>
    <td style="width: 47%">&#160;</td></tr>
  <tr>
    <td><span style="font-family: Times New Roman, Times, Serif; font-size: 10pt">Date: August 13, 2025</span></td>
    <td style="vertical-align: bottom"><span style="font-family: Times New Roman, Times, Serif; font-size: 10pt">By:</span></td>
    <td style="border-bottom: black 1pt solid; vertical-align: bottom"><span style="font-family: Times New Roman, Times, Serif; font-size: 10pt">/s/ Brian DeSchuytner</span></td></tr>
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    <td>&#160;</td>
    <td>&#160;</td>
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    <td>&#160;</td>
    <td>&#160;</td>
    <td><span style="font-family: Times New Roman, Times, Serif; font-size: 10pt">Senior Vice President, Chief Operating Officer and Chief Financial Officer</span></td></tr>
  </table>
<p style="font: 10pt Times New Roman, Times, Serif; margin: 0pt 0">&#160;</p>

<p style="font: 10pt Times New Roman, Times, Serif; margin: 0pt 0"></p>

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<P STYLE="text-align: right; margin: 0"><B>Exhibit 99.1</B></P>

<P STYLE="margin: 0">&nbsp;</P>

<P STYLE="font: 10pt Times New Roman, Times, Serif; margin: 0pt 0; text-align: center"><B>Mersana Therapeutics Provides Business Update
and Announces<BR>
Second Quarter 2025 Financial Results</B></P>

<P STYLE="font: 10pt Times New Roman, Times, Serif; margin: 0pt 0; text-align: center">&nbsp;</P>

<TABLE CELLPADDING="0" CELLSPACING="0" STYLE="width: 100%; font: 10pt Times New Roman, Times, Serif; margin-top: 0pt; margin-bottom: 0pt"><TR STYLE="vertical-align: top; text-align: justify">
<TD STYLE="width: 0.25in"></TD><TD STYLE="width: 0.25in; text-align: left"><FONT STYLE="font-family: Symbol; color: windowtext">&middot;</FONT></TD><TD STYLE="text-align: left"><FONT STYLE="font-family: Times New Roman, Times, Serif; color: black"><I>More
than 45 patients enrolled in Emi-Le Phase 1 dose expansion cohorts in post-topoisomerase-1 inhibitor ADC (post-topo-1) triple-negative
breast cancer (TNBC)</I></FONT></TD>
</TR></TABLE>

<P STYLE="font: 10pt Times New Roman, Times, Serif; margin: 0pt 0 0pt 0.5in; text-indent: -0.25in">&nbsp;</P>

<TABLE CELLPADDING="0" CELLSPACING="0" WIDTH="100%" STYLE="font: 10pt Times New Roman, Times, Serif; margin-top: 0pt; margin-bottom: 0pt"><TR STYLE="vertical-align: top">
<TD STYLE="width: 0.25in"></TD><TD STYLE="width: 0.25in"><FONT STYLE="font-family: Symbol">&middot;</FONT></TD><TD><FONT STYLE="font-family: Times New Roman, Times, Serif"><I>Plan to report initial clinical data from Emi-Le expansion cohorts in
second half of 2025</I></FONT></TD></TR></TABLE>

<P STYLE="margin-top: 0pt; margin-bottom: 0pt; font: 10pt Times New Roman, Times, Serif">&nbsp;</P>

<TABLE CELLPADDING="0" CELLSPACING="0" STYLE="width: 100%; font: 10pt Times New Roman, Times, Serif; margin-top: 0pt; margin-bottom: 0pt"><TR STYLE="vertical-align: top; text-align: justify">
<TD STYLE="width: 0.25in"></TD><TD STYLE="width: 0.25in; text-align: left"><FONT STYLE="font-family: Symbol">&middot;</FONT></TD><TD STYLE="text-align: left"><FONT STYLE="font-family: Times New Roman, Times, Serif"><I>Conference
call today at 8:00 a.m. ET</I></FONT></TD>
</TR></TABLE>

<P STYLE="font: 10pt Times New Roman, Times, Serif; margin: 0pt 0 0pt 0.5in; text-align: justify; text-indent: -0.25in">&nbsp;</P>

<P STYLE="font: 10pt Times New Roman, Times, Serif; margin: 0pt 0"><B>CAMBRIDGE, Mass., August 13, 2025</B> &ndash; Mersana Therapeutics,
Inc. (NASDAQ: MRSN), a clinical-stage biopharmaceutical company focused on the development 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 second quarter ended
June 30, 2025.</P>

<P STYLE="font: 10pt Times New Roman, Times, Serif; margin: 0pt 0">&nbsp;</P>

<P STYLE="font: 10pt Times New Roman, Times, Serif; margin: 0pt 0">&ldquo;During the second quarter, we were excited to have Emi-Le clinical
data presented in oral sessions at both ASCO 2025 and ESMO Breast Cancer 2025. These presentations highlighted Emi-Le&rsquo;s encouraging
clinical activity in patients with TNBC post-topo-1 treatment and those with adenoid cystic carcinoma type 1 (ACC-1),&rdquo; said Martin
Huber, M.D., President and Chief Executive Officer of Mersana Therapeutics. &ldquo;Our team has continued to make important progress in
recent months, as evidenced by the strong pace of enrollment in the two ongoing dose expansion cohorts in our Phase 1 clinical trial of
Emi-Le. We look forward to reporting initial clinical data from these expansion cohorts later this year.&rdquo;</P>

<P STYLE="font: 10pt Times New Roman, Times, Serif; margin: 0pt 0">&nbsp;</P>

<P STYLE="font: 10pt Times New Roman, Times, Serif; margin: 0pt 0"><B><U>Emiltatug Ledadotin (Emi-Le; XMT-1660)</U></B></P>

<P STYLE="font: 10pt Times New Roman, Times, Serif; margin: 0pt 0">&nbsp;</P>

<P STYLE="font: 10pt Times New Roman, Times, Serif; margin: 0pt 0">Mersana has continued to advance the development of Emi-Le, the company&rsquo;s
B7-H4-directed Dolasynthen ADC.</P>

<P STYLE="font: 10pt Times New Roman, Times, Serif; margin: 0pt 0">&nbsp;</P>

<P STYLE="font: 10pt Times New Roman, Times, Serif; margin: 0pt 0"><FONT STYLE="font-family: Times New Roman, Times, Serif; font-size: 10pt"><B>Medical
Congress Presentations:</B></FONT> During the second quarter of 2025, clinical data as of a March 8, 2025 data cut-off from dose escalation
and backfill cohorts in the Phase 1 clinical trial of Emi-Le were included in oral presentations at the American Society of Clinical
Oncology&nbsp;2025 Annual Meeting (ASCO 2025) in&nbsp;Chicago, IL and the&nbsp;European Society for Medical Oncology Breast Cancer&nbsp;2025
Annual Congress (ESMO Breast Cancer 2025) in&nbsp;Munich, Germany. The ASCO 2025 presentation included data for patients across all enrolled
tumor types, and the ESMO Breast Cancer 2025 presentation focused primarily on patients with post-topo-1 TNBC. These presentations can
be accessed by visiting the Publications section of the Mersana website at&nbsp;<U>www.mersana.com</U>.</P>

<P STYLE="font: 10pt Times New Roman, Times, Serif; margin: 0pt 0">&nbsp;</P>

<P STYLE="font: 10pt Times New Roman, Times, Serif; margin: 0pt 0"><FONT STYLE="font-family: Times New Roman, Times, Serif; font-size: 10pt"><B>Expansion
Update:</B></FONT> Mersana continues to enroll patients with TNBC who have received one to four prior lines of therapy, including at least
one topo-1 ADC. This stage of the trial is enrolling patients in two cohorts:</P>

<P STYLE="margin-top: 0; margin-bottom: 0">&nbsp;</P>

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<TD STYLE="width: 0.25in"></TD><TD STYLE="width: 0.25in"><FONT STYLE="font-family: Symbol; color: black">&middot;</FONT></TD><TD><FONT STYLE="font-family: Times New Roman, Times, Serif">A &ldquo;Dose A&rdquo; cohort, in which patients are receiving 67.4 mg/m<SUP>2</SUP>
of Emi-Le every four weeks (Q4W), and</FONT></TD></TR></TABLE>

<TABLE CELLPADDING="0" CELLSPACING="0" WIDTH="100%" STYLE="font: 10pt Times New Roman, Times, Serif; margin-top: 0pt; margin-bottom: 0pt"><TR STYLE="vertical-align: top">
<TD STYLE="width: 0.25in"></TD><TD STYLE="width: 0.25in"><FONT STYLE="font-family: Symbol; color: black">&middot;</FONT></TD><TD><FONT STYLE="font-family: Times New Roman, Times, Serif">A &ldquo;Dose B&rdquo; cohort, in which patients are receiving 80 mg/m<SUP>2</SUP>
Q4W following a loading dose of 44.5 mg/m<SUP>2</SUP> on days 1 and 8 of the first four-week cycle. </FONT></TD></TR></TABLE>

<P STYLE="font: 10pt Times New Roman, Times, Serif; margin: 0pt 0">&nbsp;</P>

<P STYLE="font: 10pt Times New Roman, Times, Serif; margin: 0pt 0"></P>

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<P STYLE="font: 10pt Times New Roman, Times, Serif; margin: 0pt 0">&nbsp;</P>

<P STYLE="font: 10pt Times New Roman, Times, Serif; margin: 0pt 0">Collectively, more than 45 patients with TNBC have been enrolled across
the two cohorts. Mersana plans to report initial clinical data from the expansion portion of its Phase 1 clinical trial in the second
half of 2025.</P>

<P STYLE="font: 10pt Times New Roman, Times, Serif; margin: 0pt 0">&nbsp;</P>

<P STYLE="font: 10pt Times New Roman, Times, Serif; margin: 0pt 0"><B><U>XMT-2056</U></B></P>

<P STYLE="font: 10pt Times New Roman, Times, Serif; margin: 0pt 0">&nbsp;</P>

<P STYLE="font: 10pt Times New Roman, Times, Serif; margin: 0pt 0">The dose escalation portion of Mersana&rsquo;s Phase 1 clinical trial
of XMT-2056, the company&rsquo;s lead Immunosynthen ADC candidate targeting a novel HER2 epitope, is ongoing. Additionally, in July 2025,
Mersana achieved a $15 million development milestone under its agreement with GSK plc, which has an exclusive global license option to
co-develop and commercialize XMT-2056.&nbsp;Payment of the milestone is due in the third quarter of 2025. Mersana expects to present initial
clinical pharmacodynamic STING activation data for XMT-2056 in the second half of 2025.</P>

<P STYLE="font: 10pt Times New Roman, Times, Serif; margin: 0pt 0">&nbsp;</P>

<P STYLE="font: 10pt Times New Roman, Times, Serif; margin: 0pt 0"><B><U>Collaborations</U></B></P>

<P STYLE="font: 10pt Times New Roman, Times, Serif; margin: 0pt 0">&nbsp;</P>

<P STYLE="font: 10pt Times New Roman, Times, Serif; margin: 0pt 0">Mersana continues to support its collaborations with both Johnson &amp;
Johnson (Dolasynthen research collaboration) and Merck KGaA, Darmstadt, Germany (Immunosynthen research collaboration).</P>

<P STYLE="font: 10pt Times New Roman, Times, Serif; margin: 0pt 0">&nbsp;</P>

<P STYLE="font: 10pt Times New Roman, Times, Serif; margin: 0pt 0"><B><U>Reverse Stock Split</U></B></P>

<P STYLE="font: 10pt Times New Roman, Times, Serif; margin: 0pt 0">&nbsp;</P>

<P STYLE="font: 10pt Times New Roman, Times, Serif; margin: 0pt 0">A 1-for-25 reverse stock split of the issued and outstanding shares
of Mersana&rsquo;s common stock (the Reverse Stock Split) became effective at 5:00 p.m. ET on July 25, 2025, and the company&rsquo;s common
stock began trading on a split-adjusted basis on July 28, 2025. The Reverse Stock Split reduced the number of outstanding shares of the
company&rsquo;s common stock from approximately 124.8 million shares to approximately 5.0 million shares. The shares outstanding and per
share amounts below have been adjusted to reflect the Reverse Stock Split.</P>

<P STYLE="font: 10pt Times New Roman, Times, Serif; margin: 0pt 0">&nbsp;</P>

<P STYLE="font: 10pt Times New Roman, Times, Serif; margin: 0pt 0">On August 11, 2025, the company received formal notification from The
Nasdaq Stock Market, LLC (Nasdaq) confirming that the company has regained compliance with Nasdaq&rsquo;s minimum bid price requirement.
The regaining of compliance is a result of the closing bid price per share of the company&rsquo;s common stock being at least $1.00 for
a minimum of 10 consecutive business days prior to the August 25, 2025 compliance deadline, as described in the initial notice from Nasdaq
to the company dated February 25, 2025.</P>

<P STYLE="font: 10pt Times New Roman, Times, Serif; margin: 0pt 0">&nbsp;</P>

<P STYLE="font: 10pt Times New Roman, Times, Serif; margin: 0pt 0"><B><U>Second Quarter 2025 Financial Results and Recent Updates</U></B></P>

<P STYLE="font: 10pt Times New Roman, Times, Serif; margin: 0pt 0">&nbsp;</P>

<TABLE CELLPADDING="0" CELLSPACING="0" WIDTH="100%" STYLE="font: 10pt Times New Roman, Times, Serif; margin-top: 0pt; margin-bottom: 0pt"><TR STYLE="vertical-align: top">
<TD STYLE="width: 0.25in"></TD><TD STYLE="width: 0.25in"><FONT STYLE="font-family: Symbol; color: black">&middot;</FONT></TD><TD><FONT STYLE="font-family: Times New Roman, Times, Serif">Net cash used in operating activities for the second quarter of 2025 was
$22.6 million, which included $2.4 million in severance-related payments.</FONT></TD></TR></TABLE>

<P STYLE="margin-top: 0pt; margin-bottom: 0pt; font: 10pt Times New Roman, Times, Serif">&nbsp;</P>

<TABLE CELLPADDING="0" CELLSPACING="0" WIDTH="100%" STYLE="font: 10pt Times New Roman, Times, Serif; margin-top: 0pt; margin-bottom: 0pt"><TR STYLE="vertical-align: top">
<TD STYLE="width: 0.25in"></TD><TD STYLE="width: 0.25in"><FONT STYLE="font-family: Symbol; color: black">&middot;</FONT></TD><TD><FONT STYLE="font-family: Times New Roman, Times, Serif">Cash and cash equivalents as of June 30, 2025 were $77.0 million. </FONT></TD></TR></TABLE>

<P STYLE="margin-top: 0pt; margin-bottom: 0pt; font: 10pt Times New Roman, Times, Serif">&nbsp;</P>

<TABLE CELLPADDING="0" CELLSPACING="0" WIDTH="100%" STYLE="font: 10pt Times New Roman, Times, Serif; margin-top: 0pt; margin-bottom: 0pt"><TR STYLE="vertical-align: top">
<TD STYLE="width: 0.25in"></TD><TD STYLE="width: 0.25in"><FONT STYLE="font-family: Symbol; color: black">&middot;</FONT></TD><TD><FONT STYLE="font-family: Times New Roman, Times, Serif">In July 2025, Mersana made a payment of approximately $17.9 million to satisfy
in full its indebtedness and obligations under the company&rsquo;s previous loan and security agreement. The company continues to expect
that its capital resources will be sufficient to support its current operating plan commitments into mid-2026.</FONT></TD></TR></TABLE>

<P STYLE="margin-top: 0pt; margin-bottom: 0pt; font: 10pt Times New Roman, Times, Serif">&nbsp;</P>

<TABLE CELLPADDING="0" CELLSPACING="0" WIDTH="100%" STYLE="font: 10pt Times New Roman, Times, Serif; margin-top: 0pt; margin-bottom: 0pt"><TR STYLE="vertical-align: top">
<TD STYLE="width: 0.25in"></TD><TD STYLE="width: 0.25in"><FONT STYLE="font-family: Symbol">&middot;</FONT></TD><TD><FONT STYLE="font-family: Times New Roman, Times, Serif">Collaboration revenue for the second quarter of 2025 was $3.1 million, compared
to $2.3 million for the same period in 2024. The year-over-year change was primarily related to increased revenue recognized under the
company&rsquo;s collaboration and license agreements with Johnson&nbsp;&amp; Johnson and Merck KGaA, Darmstadt, Germany, partially offset
by reduced revenue recognized under its agreement with GSK. </FONT></TD></TR></TABLE>

<P STYLE="margin-top: 0pt; margin-bottom: 0pt; font: 10pt Times New Roman, Times, Serif">&nbsp;</P>

<P STYLE="font: 10pt Times New Roman, Times, Serif; margin-top: 0pt; margin-bottom: 0pt"></P>

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<P STYLE="font: 10pt Times New Roman, Times, Serif; margin-top: 0pt; margin-bottom: 0pt">&nbsp;</P>

<TABLE CELLPADDING="0" CELLSPACING="0" WIDTH="100%" STYLE="font: 10pt Times New Roman, Times, Serif; margin-top: 0pt; margin-bottom: 0pt"><TR STYLE="vertical-align: top">
<TD STYLE="width: 0.25in"></TD><TD STYLE="width: 0.25in"><FONT STYLE="font-family: Symbol">&middot;</FONT></TD><TD><FONT STYLE="font-family: Times New Roman, Times, Serif">Research and development (R&amp;D) expense for the second quarter of 2025
was $16.2 million, compared to $17.2 million for the same period in 2024. Included in the second quarter of 2025 R&amp;D expense was $0.9
million in non-cash stock-based compensation expense. The year-over-year change in R&amp;D expense was primarily related to lower headcount
and related employee compensation costs, partially offset by an increase in costs related to Emi-Le and XMT- 2056 clinical development
activities and manufacturing activities associated with the company&rsquo;s collaborations. </FONT></TD></TR></TABLE>

<P STYLE="margin-top: 0pt; margin-bottom: 0pt; font: 10pt Times New Roman, Times, Serif">&nbsp;</P>

<TABLE CELLPADDING="0" CELLSPACING="0" WIDTH="100%" STYLE="font: 10pt Times New Roman, Times, Serif; margin-top: 0pt; margin-bottom: 0pt"><TR STYLE="vertical-align: top">
<TD STYLE="width: 0.25in"></TD><TD STYLE="width: 0.25in"><FONT STYLE="font-family: Symbol; color: windowtext">&middot;</FONT></TD><TD><FONT STYLE="font-family: Times New Roman, Times, Serif">General and administrative (G&amp;A) expense for the second quarter of 2025
was $7.4 million, compared to $10.5 million during the same period in 2024<FONT STYLE="color: windowtext">. Included in the second quarter
of 2025 G&amp;A expense was $1.1 million in non-cash stock-based compensation expenses. The year-over-year change in G&amp;A expense was
primarily related to lower headcount and related employee compensation costs and a reduction in consulting and professional services fees.</FONT></FONT></TD></TR></TABLE>

<P STYLE="margin-top: 0pt; margin-bottom: 0pt; font: 10pt Times New Roman, Times, Serif">&nbsp;</P>

<TABLE CELLPADDING="0" CELLSPACING="0" WIDTH="100%" STYLE="font: 10pt Times New Roman, Times, Serif; margin-top: 0pt; margin-bottom: 0pt"><TR STYLE="vertical-align: top">
<TD STYLE="width: 0.25in"></TD><TD STYLE="width: 0.25in"><FONT STYLE="font-family: Symbol">&middot;</FONT></TD><TD><FONT STYLE="font-family: Times New Roman, Times, Serif">Mersana incurred $3.9 million in restructuring expenses for the second quarter
of 2025 related primarily to severance and benefit payments, outplacement services and related expenses.</FONT></TD></TR></TABLE>

<P STYLE="margin-top: 0pt; margin-bottom: 0pt; font: 10pt Times New Roman, Times, Serif">&nbsp;</P>

<TABLE CELLPADDING="0" CELLSPACING="0" WIDTH="100%" STYLE="font: 10pt Times New Roman, Times, Serif; margin-top: 0pt; margin-bottom: 0pt"><TR STYLE="vertical-align: top">
<TD STYLE="width: 0.25in"></TD><TD STYLE="width: 0.25in"><FONT STYLE="font-family: Symbol">&middot;</FONT></TD><TD><FONT STYLE="font-family: Times New Roman, Times, Serif">Net loss for the second quarter of 2025 was $24.3 million, or $4.87 per share,
compared to a net loss of $24.3 million, or $4.96 per share, for the same period in 2024. </FONT></TD></TR></TABLE>

<P STYLE="margin-top: 0pt; margin-bottom: 0pt; font: 10pt Times New Roman, Times, Serif">&nbsp;</P>

<P STYLE="font: 10pt Times New Roman, Times, Serif; margin: 0pt 0"><B><U>Conference Call Reminder</U></B></P>

<P STYLE="font: 10pt Times New Roman, Times, Serif; margin: 0pt 0">&nbsp;</P>

<P STYLE="font: 10pt Times New Roman, Times, Serif; margin: 0pt 0">Mersana will host a conference call today at 8:00 a.m. ET to discuss
business updates and its financial results for the second quarter of 2025. To access the call, please dial 833-255-2826 (domestic) or
412-317-0689 (international). A live webcast of the presentation will be available on the Investors &amp; Media section of the Mersana
website at www.mersana.com, and a replay of the webcast will be available in the same location following the conference call for approximately
90 days.</P>

<P STYLE="font: 10pt Times New Roman, Times, Serif; margin: 0pt 0">&nbsp;</P>

<P STYLE="font: 10pt Times New Roman, Times, Serif; margin: 0pt 0"><B><U>About Mersana Therapeutics</U></B></P>

<P STYLE="font: 10pt Times New Roman, Times, Serif; margin: 0pt 0">&nbsp;</P>

<P STYLE="font: 10pt Times New Roman, Times, Serif; margin: 0pt 0"><FONT STYLE="color: black; background-color: white">Mersana Therapeutics
is a clinical-stage biopharmaceutical company focused on the development of novel antibody-drug conjugates (ADCs) and driven by the knowledge
that patients are waiting for new treatment options. The company has developed proprietary cytotoxic (Dolasynthen) and immunostimulatory
(Immunosynthen) ADC platforms that have generated a pipeline of wholly-owned and partnered product candidates with the potential to treat
a range of cancers. Its pipeline includes Emi-Le (emiltatug ledadotin; XMT-1660), a Dolasynthen ADC targeting B7-H4, and XMT-2056, an
Immunosynthen ADC targeting a novel epitope of human epidermal growth factor receptor 2 (HER2). Mersana routinely posts information that
may be useful to investors on the &ldquo;Investors &amp; Media&rdquo; section of its website at </FONT><FONT STYLE="background-color: white">www.mersana.com.
</FONT></P>

<P STYLE="font: 10pt Times New Roman, Times, Serif; margin: 0pt 0">&nbsp;</P>

<P STYLE="font: 10pt Times New Roman, Times, Serif; margin: 0pt 0"></P>

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<P STYLE="font: 10pt Times New Roman, Times, Serif; margin: 0pt 0">&nbsp;</P>

<P STYLE="font: 10pt Times New Roman, Times, Serif; margin: 0pt 0"><B><U>Forward-Looking Statements</U></B></P>

<P STYLE="font: 10pt Times New Roman, Times, Serif; margin: 0pt 0">&nbsp;</P>

<P STYLE="font: 10pt Times New Roman, Times, Serif; margin: 0pt 0"><FONT STYLE="font-family: Times New Roman, Times, Serif; font-size: 10pt; background-color: white">This
press release contains &ldquo;forward-looking&rdquo; statements and information within the meaning of the Private Securities Litigation
Reform Act of 1995. These statements may be identified by words such as &ldquo;aims,&rdquo; &ldquo;anticipates,&rdquo; &ldquo;believes,&rdquo;
&ldquo;could,&rdquo; &ldquo;estimates,&rdquo; &ldquo;expects,&rdquo; &ldquo;forecasts,&rdquo; &ldquo;goal,&rdquo; &ldquo;intends,&rdquo;
&ldquo;may,&rdquo; &ldquo;plans,&rdquo; &ldquo;possible,&rdquo; &ldquo;potential,&rdquo; &ldquo;seeks,&rdquo; &ldquo;will&rdquo; and variations
of these words or similar expressions, although not all forward-looking statements contain these words. Forward-looking statements in
this press release include, but are not limited to, statements concerning </FONT><FONT STYLE="background-color: white">Mersana&rsquo;s
strategic priorities; its plans regarding the clinical development of Emi-Le and XMT-2056, including with respect to the progress and
design of the clinical trials of these product candidates; the potential clinical benefits of and opportunity for Emi-Le; Mersana&rsquo;s
planned data presentations, including with respect to data from the expansion portion of its Phase 1 clinical trial of Emi-Le and to clinical
pharmacodynamic STING activation data related to XMT-2056; Mersana&rsquo;s collaborations with third parties; the development and potential
of Mersana&rsquo;s product candidates, platforms, technology and pipeline of ADC candidates; and Mersana&rsquo;s expected cash runway.
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 advancement, progression and completion of clinical trials and in the clinical development
of Mersana&rsquo;s product candidates, including Emi-Le and XMT-2056; the risk that Mersana may face delays in patient enrollment in its
Phase 1 clinical trials of Emi-Le and XMT-2056; the risk that outcomes of preclinical studies may not be predictive of clinical trial
results; the risk that initial or interim results from a clinical trial may not be predictive of the final results of the trial or the
results of future trials; the risk that clinical trial data may not support regulatory applications or approvals; the risk that Mersana
may not realize the intended benefits of its platforms, technology and collaborations; the risk that Mersana's projections regarding its
expected cash runway are inaccurate or that the conduct of its business requires more cash than anticipated; the occurrence of impediments
to Mersana&rsquo;s ability to execute its previously announced strategic restructuring and reprioritization plan as and on the timeline
originally contemplated; the risk that restructuring costs and charges may be greater than anticipated; the risk that Mersana&rsquo;s
restructuring and reprioritization efforts may adversely affect its ability to retain skilled and motivated personnel and may be distracting
to employees and management; the risk that Mersana&rsquo;s restructuring efforts may negatively impact its business operations and reputation;
the risk that Mersana&rsquo;s restructuring efforts may not generate their intended benefits to the extent or as quickly as anticipated;
and other important factors, any of which could cause Mersana&rsquo;s actual results to differ from those contained in the forward-looking
statements, that are described in greater detail in the section entitled &ldquo;Risk Factors&rdquo; in Mersana&rsquo;s Quarterly Report
on Form 10-Q filed with the Securities and Exchange Commission (SEC) on May 15, 2025, as well as in other filings Mersana may make with
the SEC in the future. Any forward-looking statements contained in this press release speak only as of the date hereof, and Mersana expressly
disclaims any obligation to update any forward-looking statements contained herein, whether because of any new information, future events,
changed circumstances or otherwise, except as otherwise required by law.</FONT></P>

<P STYLE="font: 10pt Times New Roman, Times, Serif; margin: 0pt 0">&nbsp;</P>

<P STYLE="font: 10pt Times New Roman, Times, Serif; margin: 0pt 0"></P>

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<P STYLE="font: 10pt Times New Roman, Times, Serif; margin: 0pt 0">&nbsp;</P>

<P STYLE="font: 10pt Times New Roman, Times, Serif; margin: 0pt 0; text-align: center"><B>Mersana Therapeutics, Inc.</B></P>

<P STYLE="font: 10pt Times New Roman, Times, Serif; margin: 0pt 0; text-align: center"><B>Selected Condensed Consolidated Balance Sheet
Data</B></P>

<P STYLE="font: 10pt Times New Roman, Times, Serif; margin: 0pt 0; text-align: center"><FONT STYLE="font-family: Times New Roman, Times, Serif; font-size: 10pt"><B>(in
thousands and </B></FONT><B>unaudited)</B></P>

<P STYLE="font: 10pt Times New Roman, Times, Serif; margin: 0pt 0">&nbsp;</P>

<TABLE CELLPADDING="0" CELLSPACING="0" STYLE="border-collapse: collapse; width: 80%; font: 10pt Times New Roman, Times, Serif; margin-right: 1.5in">
  <TR STYLE="vertical-align: bottom">
    <TD STYLE="font-size: 10pt">&nbsp;</TD><TD STYLE="font: bold 10pt Times New Roman, Times, Serif">&nbsp;</TD>
    <TD COLSPAN="2" STYLE="font: bold 10pt Times New Roman, Times, Serif; text-align: center">June 30,</TD><TD STYLE="font: bold 10pt Times New Roman, Times, Serif">&nbsp;</TD><TD STYLE="font: bold 10pt Times New Roman, Times, Serif">&nbsp;</TD>
    <TD COLSPAN="2" STYLE="font: bold 10pt Times New Roman, Times, Serif; text-align: center">December 31,</TD><TD STYLE="font: bold 10pt Times New Roman, Times, Serif">&nbsp;</TD></TR>
  <TR STYLE="vertical-align: bottom">
    <TD STYLE="font-size: 10pt">&nbsp;</TD><TD STYLE="font: bold 10pt Times New Roman, Times, Serif; padding-bottom: 1pt">&nbsp;</TD>
    <TD COLSPAN="2" STYLE="font: bold 10pt Times New Roman, Times, Serif; text-align: center; border-bottom: Black 1pt solid">2025</TD><TD STYLE="padding-bottom: 1pt; font: bold 10pt Times New Roman, Times, Serif">&nbsp;</TD><TD STYLE="font: bold 10pt Times New Roman, Times, Serif; padding-bottom: 1pt">&nbsp;</TD>
    <TD COLSPAN="2" STYLE="font: bold 10pt Times New Roman, Times, Serif; text-align: center; border-bottom: Black 1pt solid">2024</TD><TD STYLE="padding-bottom: 1pt; font: bold 10pt Times New Roman, Times, Serif">&nbsp;</TD></TR>
  <TR STYLE="vertical-align: bottom; background-color: rgb(204,238,255)">
    <TD STYLE="font: 10pt Times New Roman, Times, Serif; width: 69%; text-align: left">Cash, cash equivalents and marketable securities</TD><TD STYLE="width: 2%; font: 10pt Times New Roman, Times, Serif">&nbsp;</TD>
    <TD STYLE="width: 1%; font: 10pt Times New Roman, Times, Serif; text-align: left">$</TD><TD STYLE="width: 12%; font: 10pt Times New Roman, Times, Serif; text-align: right">76,972</TD><TD STYLE="width: 1%; font: 10pt Times New Roman, Times, Serif; text-align: left">&nbsp;</TD><TD STYLE="width: 1%; font: 10pt Times New Roman, Times, Serif">&nbsp;</TD>
    <TD STYLE="width: 1%; font: 10pt Times New Roman, Times, Serif; text-align: left">$</TD><TD STYLE="width: 12%; font: 10pt Times New Roman, Times, Serif; text-align: right">134,620</TD><TD STYLE="width: 1%; font: 10pt Times New Roman, Times, Serif; text-align: left">&nbsp;</TD></TR>
  <TR STYLE="vertical-align: bottom; background-color: White">
    <TD STYLE="font: 10pt Times New Roman, Times, Serif; text-align: left">Total assets</TD><TD STYLE="font: 10pt Times New Roman, Times, Serif">&nbsp;</TD>
    <TD STYLE="font: 10pt Times New Roman, Times, Serif; text-align: left">&nbsp;</TD><TD STYLE="font: 10pt Times New Roman, Times, Serif; text-align: right">84,573</TD><TD STYLE="font: 10pt Times New Roman, Times, Serif; text-align: left">&nbsp;</TD><TD STYLE="font: 10pt Times New Roman, Times, Serif">&nbsp;</TD>
    <TD STYLE="font: 10pt Times New Roman, Times, Serif; text-align: left">&nbsp;</TD><TD STYLE="font: 10pt Times New Roman, Times, Serif; text-align: right">144,663</TD><TD STYLE="font: 10pt Times New Roman, Times, Serif; text-align: left">&nbsp;</TD></TR>
  <TR STYLE="vertical-align: bottom; background-color: rgb(204,238,255)">
    <TD STYLE="font: 10pt Times New Roman, Times, Serif; text-align: left">Total liabilities</TD><TD STYLE="font: 10pt Times New Roman, Times, Serif">&nbsp;</TD>
    <TD STYLE="font: 10pt Times New Roman, Times, Serif; text-align: left">&nbsp;</TD><TD STYLE="font: 10pt Times New Roman, Times, Serif; text-align: right">137,719</TD><TD STYLE="font: 10pt Times New Roman, Times, Serif; text-align: left">&nbsp;</TD><TD STYLE="font: 10pt Times New Roman, Times, Serif">&nbsp;</TD>
    <TD STYLE="font: 10pt Times New Roman, Times, Serif; text-align: left">&nbsp;</TD><TD STYLE="font: 10pt Times New Roman, Times, Serif; text-align: right">154,172</TD><TD STYLE="font: 10pt Times New Roman, Times, Serif; text-align: left">&nbsp;</TD></TR>
  <TR STYLE="vertical-align: bottom; background-color: White">
    <TD STYLE="font: 10pt Times New Roman, Times, Serif; text-align: left">Total stockholders' deficit</TD><TD STYLE="font: 10pt Times New Roman, Times, Serif">&nbsp;</TD>
    <TD STYLE="font: 10pt Times New Roman, Times, Serif; text-align: left">&nbsp;</TD><TD STYLE="font: 10pt Times New Roman, Times, Serif; text-align: right">(53,146</TD><TD STYLE="font: 10pt Times New Roman, Times, Serif; text-align: left">)</TD><TD STYLE="font: 10pt Times New Roman, Times, Serif">&nbsp;</TD>
    <TD STYLE="font: 10pt Times New Roman, Times, Serif; text-align: left">&nbsp;</TD><TD STYLE="font: 10pt Times New Roman, Times, Serif; text-align: right">(9,509</TD><TD STYLE="font: 10pt Times New Roman, Times, Serif; text-align: left">)</TD></TR>
  </TABLE>

<P STYLE="font: 10pt Times New Roman, Times, Serif; margin: 0pt 0">&nbsp;</P>

<P STYLE="font: 10pt Times New Roman, Times, Serif; margin: 0pt 0; text-align: center"><B>Mersana Therapeutics, Inc.</B></P>

<P STYLE="font: 10pt Times New Roman, Times, Serif; margin: 0pt 0; text-align: center"><B>Condensed Consolidated Statement of Operations</B></P>

<P STYLE="font: 10pt Times New Roman, Times, Serif; margin: 0pt 0; text-align: center"><FONT STYLE="font-family: Times New Roman, Times, Serif; font-size: 10pt"><B>(in
thousands, except share and per share data, and </B></FONT><B>unaudited)</B></P>

<P STYLE="font: 10pt Times New Roman, Times, Serif; margin: 0pt 0">&nbsp;</P>

<TABLE CELLPADDING="0" CELLSPACING="0" STYLE="border-collapse: collapse; width: 100%; font: 10pt Times New Roman, Times, Serif">
  <TR STYLE="vertical-align: bottom">
    <TD STYLE="font-size: 10pt; font-weight: bold; text-align: center">&nbsp;</TD><TD STYLE="padding-bottom: 1pt; font-size: 10pt; font-weight: bold">&nbsp;</TD>
    <TD COLSPAN="6" STYLE="border-bottom: Black 1pt solid; font-size: 10pt; font-weight: bold; text-align: center">Three months ended</TD><TD STYLE="padding-bottom: 1pt; font-size: 10pt; font-weight: bold">&nbsp;</TD><TD STYLE="padding-bottom: 1pt; font-size: 10pt; font-weight: bold">&nbsp;</TD>
    <TD COLSPAN="6" STYLE="border-bottom: Black 1pt solid; font-size: 10pt; font-weight: bold; text-align: center">Six months ended</TD><TD STYLE="padding-bottom: 1pt; font-size: 10pt; font-weight: bold">&nbsp;</TD></TR>
  <TR STYLE="vertical-align: bottom">
    <TD STYLE="font-size: 10pt; font-weight: bold; text-align: center">&nbsp;</TD><TD STYLE="font-size: 10pt; font-weight: bold">&nbsp;</TD>
    <TD COLSPAN="2" STYLE="font-size: 10pt; font-weight: bold; text-align: center">June 30,</TD><TD STYLE="font-size: 10pt; font-weight: bold">&nbsp;</TD><TD STYLE="font-size: 10pt; font-weight: bold">&nbsp;</TD>
    <TD COLSPAN="2" STYLE="font-size: 10pt; font-weight: bold; text-align: center">June 30,</TD><TD STYLE="font-size: 10pt; font-weight: bold">&nbsp;</TD><TD STYLE="font-size: 10pt; font-weight: bold">&nbsp;</TD>
    <TD COLSPAN="2" STYLE="font-size: 10pt; font-weight: bold; text-align: center">June 30,</TD><TD STYLE="font-size: 10pt; font-weight: bold">&nbsp;</TD><TD STYLE="font-size: 10pt; font-weight: bold">&nbsp;</TD>
    <TD COLSPAN="2" STYLE="font-size: 10pt; font-weight: bold; text-align: center">June 30,</TD><TD STYLE="font-size: 10pt; font-weight: bold">&nbsp;</TD></TR>
  <TR STYLE="vertical-align: bottom">
    <TD STYLE="font-size: 10pt; font-weight: bold; text-align: center">&nbsp;</TD><TD STYLE="padding-bottom: 1pt; font-size: 10pt; font-weight: bold">&nbsp;</TD>
    <TD COLSPAN="2" STYLE="border-bottom: Black 1pt solid; font-size: 10pt; font-weight: bold; text-align: center">2025</TD><TD STYLE="padding-bottom: 1pt; font-size: 10pt; font-weight: bold">&nbsp;</TD><TD STYLE="padding-bottom: 1pt; font-size: 10pt; font-weight: bold">&nbsp;</TD>
    <TD COLSPAN="2" STYLE="border-bottom: Black 1pt solid; font-size: 10pt; font-weight: bold; text-align: center">2024</TD><TD STYLE="padding-bottom: 1pt; font-size: 10pt; font-weight: bold">&nbsp;</TD><TD STYLE="padding-bottom: 1pt; font-size: 10pt; font-weight: bold">&nbsp;</TD>
    <TD COLSPAN="2" STYLE="border-bottom: Black 1pt solid; font-size: 10pt; font-weight: bold; text-align: center">2025</TD><TD STYLE="padding-bottom: 1pt; font-size: 10pt; font-weight: bold">&nbsp;</TD><TD STYLE="padding-bottom: 1pt; font-size: 10pt; font-weight: bold">&nbsp;</TD>
    <TD COLSPAN="2" STYLE="border-bottom: Black 1pt solid; font-size: 10pt; font-weight: bold; text-align: center">2024</TD><TD STYLE="padding-bottom: 1pt; font-size: 10pt; font-weight: bold">&nbsp;</TD></TR>
  <TR STYLE="vertical-align: bottom; background-color: rgb(204,238,255)">
    <TD STYLE="font: 10pt Times New Roman, Times, Serif; width: 44%; text-align: left">Collaboration revenue</TD><TD STYLE="width: 2%; font: 10pt Times New Roman, Times, Serif">&nbsp;</TD>
    <TD STYLE="width: 1%; font: 10pt Times New Roman, Times, Serif; text-align: left">$</TD><TD STYLE="width: 10%; font: 10pt Times New Roman, Times, Serif; text-align: right">3,056</TD><TD STYLE="width: 1%; font: 10pt Times New Roman, Times, Serif; text-align: left">&nbsp;</TD><TD STYLE="width: 2%; font: 10pt Times New Roman, Times, Serif">&nbsp;</TD>
    <TD STYLE="width: 1%; font: 10pt Times New Roman, Times, Serif; text-align: left">$</TD><TD STYLE="width: 10%; font: 10pt Times New Roman, Times, Serif; text-align: right">2,293</TD><TD STYLE="width: 1%; font: 10pt Times New Roman, Times, Serif; text-align: left">&nbsp;</TD><TD STYLE="width: 2%; font: 10pt Times New Roman, Times, Serif">&nbsp;</TD>
    <TD STYLE="width: 1%; font: 10pt Times New Roman, Times, Serif; text-align: left">$</TD><TD STYLE="width: 10%; font: 10pt Times New Roman, Times, Serif; text-align: right">5,810</TD><TD STYLE="width: 1%; font: 10pt Times New Roman, Times, Serif; text-align: left">&nbsp;</TD><TD STYLE="width: 2%; font: 10pt Times New Roman, Times, Serif">&nbsp;</TD>
    <TD STYLE="width: 1%; font: 10pt Times New Roman, Times, Serif; text-align: left">$</TD><TD STYLE="width: 10%; font: 10pt Times New Roman, Times, Serif; text-align: right">11,538</TD><TD STYLE="width: 1%; font: 10pt Times New Roman, Times, Serif; text-align: left">&nbsp;</TD></TR>
  <TR STYLE="vertical-align: bottom; background-color: White">
    <TD STYLE="font-size: 10pt">&nbsp;</TD><TD STYLE="font-size: 10pt">&nbsp;</TD>
    <TD STYLE="font-size: 10pt; text-align: left">&nbsp;</TD><TD STYLE="font-size: 10pt; text-align: right">&nbsp;</TD><TD STYLE="font-size: 10pt; text-align: left">&nbsp;</TD><TD STYLE="font-size: 10pt">&nbsp;</TD>
    <TD STYLE="font-size: 10pt; text-align: left">&nbsp;</TD><TD STYLE="font-size: 10pt; text-align: right">&nbsp;</TD><TD STYLE="font-size: 10pt; text-align: left">&nbsp;</TD><TD STYLE="font-size: 10pt">&nbsp;</TD>
    <TD STYLE="font-size: 10pt; text-align: left">&nbsp;</TD><TD STYLE="font-size: 10pt; text-align: right">&nbsp;</TD><TD STYLE="font-size: 10pt; text-align: left">&nbsp;</TD><TD STYLE="font-size: 10pt">&nbsp;</TD>
    <TD STYLE="font-size: 10pt; text-align: left">&nbsp;</TD><TD STYLE="font-size: 10pt; text-align: right">&nbsp;</TD><TD STYLE="font-size: 10pt; text-align: left">&nbsp;</TD></TR>
  <TR STYLE="vertical-align: bottom; background-color: rgb(204,238,255)">
    <TD STYLE="font: 10pt Times New Roman, Times, Serif; text-align: left">Operating expenses:</TD><TD STYLE="font-size: 10pt">&nbsp;</TD>
    <TD STYLE="font-size: 10pt; text-align: left">&nbsp;</TD><TD STYLE="font-size: 10pt; text-align: right">&nbsp;</TD><TD STYLE="font-size: 10pt; text-align: left">&nbsp;</TD><TD STYLE="font-size: 10pt">&nbsp;</TD>
    <TD STYLE="font-size: 10pt; text-align: left">&nbsp;</TD><TD STYLE="font-size: 10pt; text-align: right">&nbsp;</TD><TD STYLE="font-size: 10pt; text-align: left">&nbsp;</TD><TD STYLE="font-size: 10pt">&nbsp;</TD>
    <TD STYLE="font-size: 10pt; text-align: left">&nbsp;</TD><TD STYLE="font-size: 10pt; text-align: right">&nbsp;</TD><TD STYLE="font-size: 10pt; text-align: left">&nbsp;</TD><TD STYLE="font-size: 10pt">&nbsp;</TD>
    <TD STYLE="font-size: 10pt; text-align: left">&nbsp;</TD><TD STYLE="font-size: 10pt; text-align: right">&nbsp;</TD><TD STYLE="font-size: 10pt; text-align: left">&nbsp;</TD></TR>
  <TR STYLE="vertical-align: bottom; background-color: White">
    <TD STYLE="font: 10pt Times New Roman, Times, Serif; text-align: left">Research and development</TD><TD STYLE="font: 10pt Times New Roman, Times, Serif">&nbsp;</TD>
    <TD STYLE="font: 10pt Times New Roman, Times, Serif; text-align: left">&nbsp;</TD><TD STYLE="font: 10pt Times New Roman, Times, Serif; text-align: right">16,218</TD><TD STYLE="font: 10pt Times New Roman, Times, Serif; text-align: left">&nbsp;</TD><TD STYLE="font: 10pt Times New Roman, Times, Serif">&nbsp;</TD>
    <TD STYLE="font: 10pt Times New Roman, Times, Serif; text-align: left">&nbsp;</TD><TD STYLE="font: 10pt Times New Roman, Times, Serif; text-align: right">17,245</TD><TD STYLE="font: 10pt Times New Roman, Times, Serif; text-align: left">&nbsp;</TD><TD STYLE="font: 10pt Times New Roman, Times, Serif">&nbsp;</TD>
    <TD STYLE="font: 10pt Times New Roman, Times, Serif; text-align: left">&nbsp;</TD><TD STYLE="font: 10pt Times New Roman, Times, Serif; text-align: right">34,559</TD><TD STYLE="font: 10pt Times New Roman, Times, Serif; text-align: left">&nbsp;</TD><TD STYLE="font: 10pt Times New Roman, Times, Serif">&nbsp;</TD>
    <TD STYLE="font: 10pt Times New Roman, Times, Serif; text-align: left">&nbsp;</TD><TD STYLE="font: 10pt Times New Roman, Times, Serif; text-align: right">35,931</TD><TD STYLE="font: 10pt Times New Roman, Times, Serif; text-align: left">&nbsp;</TD></TR>
  <TR STYLE="vertical-align: bottom; background-color: rgb(204,238,255)">
    <TD STYLE="font: 10pt Times New Roman, Times, Serif; text-align: left">General and administrative</TD><TD STYLE="font: 10pt Times New Roman, Times, Serif">&nbsp;</TD>
    <TD STYLE="font: 10pt Times New Roman, Times, Serif; text-align: left">&nbsp;</TD><TD STYLE="font: 10pt Times New Roman, Times, Serif; text-align: right">7,415</TD><TD STYLE="font: 10pt Times New Roman, Times, Serif; text-align: left">&nbsp;</TD><TD STYLE="font: 10pt Times New Roman, Times, Serif">&nbsp;</TD>
    <TD STYLE="font: 10pt Times New Roman, Times, Serif; text-align: left">&nbsp;</TD><TD STYLE="font: 10pt Times New Roman, Times, Serif; text-align: right">10,503</TD><TD STYLE="font: 10pt Times New Roman, Times, Serif; text-align: left">&nbsp;</TD><TD STYLE="font: 10pt Times New Roman, Times, Serif">&nbsp;</TD>
    <TD STYLE="font: 10pt Times New Roman, Times, Serif; text-align: left">&nbsp;</TD><TD STYLE="font: 10pt Times New Roman, Times, Serif; text-align: right">16,340</TD><TD STYLE="font: 10pt Times New Roman, Times, Serif; text-align: left">&nbsp;</TD><TD STYLE="font: 10pt Times New Roman, Times, Serif">&nbsp;</TD>
    <TD STYLE="font: 10pt Times New Roman, Times, Serif; text-align: left">&nbsp;</TD><TD STYLE="font: 10pt Times New Roman, Times, Serif; text-align: right">22,063</TD><TD STYLE="font: 10pt Times New Roman, Times, Serif; text-align: left">&nbsp;</TD></TR>
  <TR STYLE="vertical-align: bottom; background-color: White">
    <TD STYLE="font: 10pt Times New Roman, Times, Serif; text-align: left">Restructuring expenses</TD><TD STYLE="font: 10pt Times New Roman, Times, Serif; padding-bottom: 1pt">&nbsp;</TD>
    <TD STYLE="border-bottom: Black 1pt solid; font: 10pt Times New Roman, Times, Serif; text-align: left">&nbsp;</TD><TD STYLE="border-bottom: Black 1pt solid; font: 10pt Times New Roman, Times, Serif; text-align: right">3,940</TD><TD STYLE="padding-bottom: 1pt; font: 10pt Times New Roman, Times, Serif; text-align: left">&nbsp;</TD><TD STYLE="font: 10pt Times New Roman, Times, Serif; padding-bottom: 1pt">&nbsp;</TD>
    <TD STYLE="border-bottom: Black 1pt solid; font: 10pt Times New Roman, Times, Serif; text-align: left">&nbsp;</TD><TD STYLE="border-bottom: Black 1pt solid; font: 10pt Times New Roman, Times, Serif; text-align: right">-</TD><TD STYLE="padding-bottom: 1pt; font: 10pt Times New Roman, Times, Serif; text-align: left">&nbsp;</TD><TD STYLE="font: 10pt Times New Roman, Times, Serif; padding-bottom: 1pt">&nbsp;</TD>
    <TD STYLE="border-bottom: Black 1pt solid; font: 10pt Times New Roman, Times, Serif; text-align: left">&nbsp;</TD><TD STYLE="border-bottom: Black 1pt solid; font: 10pt Times New Roman, Times, Serif; text-align: right">3,940</TD><TD STYLE="padding-bottom: 1pt; font: 10pt Times New Roman, Times, Serif; text-align: left">&nbsp;</TD><TD STYLE="font: 10pt Times New Roman, Times, Serif; padding-bottom: 1pt">&nbsp;</TD>
    <TD STYLE="border-bottom: Black 1pt solid; font: 10pt Times New Roman, Times, Serif; text-align: left">&nbsp;</TD><TD STYLE="border-bottom: Black 1pt solid; font: 10pt Times New Roman, Times, Serif; text-align: right">-</TD><TD STYLE="padding-bottom: 1pt; font: 10pt Times New Roman, Times, Serif; text-align: left">&nbsp;</TD></TR>
  <TR STYLE="vertical-align: bottom; background-color: rgb(204,238,255)">
    <TD STYLE="font: 10pt Times New Roman, Times, Serif; text-align: left">Total operating expenses</TD><TD STYLE="font: 10pt Times New Roman, Times, Serif">&nbsp;</TD>
    <TD STYLE="font: 10pt Times New Roman, Times, Serif; text-align: left">&nbsp;</TD><TD STYLE="font: 10pt Times New Roman, Times, Serif; text-align: right">27,573</TD><TD STYLE="font: 10pt Times New Roman, Times, Serif; text-align: left">&nbsp;</TD><TD STYLE="font: 10pt Times New Roman, Times, Serif">&nbsp;</TD>
    <TD STYLE="font: 10pt Times New Roman, Times, Serif; text-align: left">&nbsp;</TD><TD STYLE="font: 10pt Times New Roman, Times, Serif; text-align: right">27,748</TD><TD STYLE="font: 10pt Times New Roman, Times, Serif; text-align: left">&nbsp;</TD><TD STYLE="font: 10pt Times New Roman, Times, Serif">&nbsp;</TD>
    <TD STYLE="font: 10pt Times New Roman, Times, Serif; text-align: left">&nbsp;</TD><TD STYLE="font: 10pt Times New Roman, Times, Serif; text-align: right">54,839</TD><TD STYLE="font: 10pt Times New Roman, Times, Serif; text-align: left">&nbsp;</TD><TD STYLE="font: 10pt Times New Roman, Times, Serif">&nbsp;</TD>
    <TD STYLE="font: 10pt Times New Roman, Times, Serif; text-align: left">&nbsp;</TD><TD STYLE="font: 10pt Times New Roman, Times, Serif; text-align: right">57,994</TD><TD STYLE="font: 10pt Times New Roman, Times, Serif; text-align: left">&nbsp;</TD></TR>
  <TR STYLE="vertical-align: bottom; background-color: White">
    <TD STYLE="font: 10pt Times New Roman, Times, Serif; text-align: left">Total other income, net</TD><TD STYLE="font: 10pt Times New Roman, Times, Serif; padding-bottom: 1pt">&nbsp;</TD>
    <TD STYLE="border-bottom: Black 1pt solid; font: 10pt Times New Roman, Times, Serif; text-align: left">&nbsp;</TD><TD STYLE="border-bottom: Black 1pt solid; font: 10pt Times New Roman, Times, Serif; text-align: right">221</TD><TD STYLE="padding-bottom: 1pt; font: 10pt Times New Roman, Times, Serif; text-align: left">&nbsp;</TD><TD STYLE="font: 10pt Times New Roman, Times, Serif; padding-bottom: 1pt">&nbsp;</TD>
    <TD STYLE="border-bottom: Black 1pt solid; font: 10pt Times New Roman, Times, Serif; text-align: left">&nbsp;</TD><TD STYLE="border-bottom: Black 1pt solid; font: 10pt Times New Roman, Times, Serif; text-align: right">1,187</TD><TD STYLE="padding-bottom: 1pt; font: 10pt Times New Roman, Times, Serif; text-align: left">&nbsp;</TD><TD STYLE="font: 10pt Times New Roman, Times, Serif; padding-bottom: 1pt">&nbsp;</TD>
    <TD STYLE="border-bottom: Black 1pt solid; font: 10pt Times New Roman, Times, Serif; text-align: left">&nbsp;</TD><TD STYLE="border-bottom: Black 1pt solid; font: 10pt Times New Roman, Times, Serif; text-align: right">610</TD><TD STYLE="padding-bottom: 1pt; font: 10pt Times New Roman, Times, Serif; text-align: left">&nbsp;</TD><TD STYLE="font: 10pt Times New Roman, Times, Serif; padding-bottom: 1pt">&nbsp;</TD>
    <TD STYLE="border-bottom: Black 1pt solid; font: 10pt Times New Roman, Times, Serif; text-align: left">&nbsp;</TD><TD STYLE="border-bottom: Black 1pt solid; font: 10pt Times New Roman, Times, Serif; text-align: right">2,882</TD><TD STYLE="padding-bottom: 1pt; font: 10pt Times New Roman, Times, Serif; text-align: left">&nbsp;</TD></TR>
  <TR STYLE="vertical-align: bottom; background-color: rgb(204,238,255)">
    <TD STYLE="font: 10pt Times New Roman, Times, Serif; text-align: left">Net loss</TD><TD STYLE="font: 10pt Times New Roman, Times, Serif">&nbsp;</TD>
    <TD STYLE="font: 10pt Times New Roman, Times, Serif; text-align: left">$</TD><TD STYLE="font: 10pt Times New Roman, Times, Serif; text-align: right">(24,296</TD><TD STYLE="font: 10pt Times New Roman, Times, Serif; text-align: left">)</TD><TD STYLE="font: 10pt Times New Roman, Times, Serif">&nbsp;</TD>
    <TD STYLE="font: 10pt Times New Roman, Times, Serif; text-align: left">$</TD><TD STYLE="font: 10pt Times New Roman, Times, Serif; text-align: right">(24,268</TD><TD STYLE="font: 10pt Times New Roman, Times, Serif; text-align: left">)</TD><TD STYLE="font: 10pt Times New Roman, Times, Serif">&nbsp;</TD>
    <TD STYLE="font: 10pt Times New Roman, Times, Serif; text-align: left">$</TD><TD STYLE="font: 10pt Times New Roman, Times, Serif; text-align: right">(48,419</TD><TD STYLE="font: 10pt Times New Roman, Times, Serif; text-align: left">)</TD><TD STYLE="font: 10pt Times New Roman, Times, Serif">&nbsp;</TD>
    <TD STYLE="font: 10pt Times New Roman, Times, Serif; text-align: left">$</TD><TD STYLE="font: 10pt Times New Roman, Times, Serif; text-align: right">(43,574</TD><TD STYLE="font: 10pt Times New Roman, Times, Serif; text-align: left">)</TD></TR>
  <TR STYLE="vertical-align: bottom; background-color: White">
    <TD STYLE="font: 10pt Times New Roman, Times, Serif; text-align: left">Net loss per share &mdash; basic and diluted</TD><TD STYLE="font: 10pt Times New Roman, Times, Serif">&nbsp;</TD>
    <TD STYLE="font: 10pt Times New Roman, Times, Serif; text-align: left">$</TD><TD STYLE="font: 10pt Times New Roman, Times, Serif; text-align: right">(4.87</TD><TD STYLE="font: 10pt Times New Roman, Times, Serif; text-align: left">)</TD><TD STYLE="font: 10pt Times New Roman, Times, Serif">&nbsp;</TD>
    <TD STYLE="font: 10pt Times New Roman, Times, Serif; text-align: left">$</TD><TD STYLE="font: 10pt Times New Roman, Times, Serif; text-align: right">(4.96</TD><TD STYLE="font: 10pt Times New Roman, Times, Serif; text-align: left">)</TD><TD STYLE="font: 10pt Times New Roman, Times, Serif">&nbsp;</TD>
    <TD STYLE="font: 10pt Times New Roman, Times, Serif; text-align: left">$</TD><TD STYLE="font: 10pt Times New Roman, Times, Serif; text-align: right">(9.72</TD><TD STYLE="font: 10pt Times New Roman, Times, Serif; text-align: left">)</TD><TD STYLE="font: 10pt Times New Roman, Times, Serif">&nbsp;</TD>
    <TD STYLE="font: 10pt Times New Roman, Times, Serif; text-align: left">$</TD><TD STYLE="font: 10pt Times New Roman, Times, Serif; text-align: right">(8.93</TD><TD STYLE="font: 10pt Times New Roman, Times, Serif; text-align: left">)</TD></TR>
  <TR STYLE="vertical-align: bottom; background-color: rgb(204,238,255)">
    <TD STYLE="font: 10pt Times New Roman, Times, Serif; text-align: left">Weighted-average number of common shares &mdash; basic and diluted</TD><TD STYLE="font: 10pt Times New Roman, Times, Serif; padding-bottom: 2.5pt">&nbsp;</TD>
    <TD STYLE="border-bottom: Black 2.5pt double; font: 10pt Times New Roman, Times, Serif; text-align: left">&nbsp;</TD><TD STYLE="border-bottom: Black 2.5pt double; font: 10pt Times New Roman, Times, Serif; text-align: right">4,986,784</TD><TD STYLE="padding-bottom: 2.5pt; font: 10pt Times New Roman, Times, Serif; text-align: left">&nbsp;</TD><TD STYLE="font: 10pt Times New Roman, Times, Serif; padding-bottom: 2.5pt">&nbsp;</TD>
    <TD STYLE="border-bottom: Black 2.5pt double; font: 10pt Times New Roman, Times, Serif; text-align: left">&nbsp;</TD><TD STYLE="border-bottom: Black 2.5pt double; font: 10pt Times New Roman, Times, Serif; text-align: right">4,897,643</TD><TD STYLE="padding-bottom: 2.5pt; font: 10pt Times New Roman, Times, Serif; text-align: left">&nbsp;</TD><TD STYLE="font: 10pt Times New Roman, Times, Serif; padding-bottom: 2.5pt">&nbsp;</TD>
    <TD STYLE="border-bottom: Black 2.5pt double; font: 10pt Times New Roman, Times, Serif; text-align: left">&nbsp;</TD><TD STYLE="border-bottom: Black 2.5pt double; font: 10pt Times New Roman, Times, Serif; text-align: right">4,982,718</TD><TD STYLE="padding-bottom: 2.5pt; font: 10pt Times New Roman, Times, Serif; text-align: left">&nbsp;</TD><TD STYLE="font: 10pt Times New Roman, Times, Serif; padding-bottom: 2.5pt">&nbsp;</TD>
    <TD STYLE="border-bottom: Black 2.5pt double; font: 10pt Times New Roman, Times, Serif; text-align: left">&nbsp;</TD><TD STYLE="border-bottom: Black 2.5pt double; font: 10pt Times New Roman, Times, Serif; text-align: right">4,877,347</TD><TD STYLE="padding-bottom: 2.5pt; font: 10pt Times New Roman, Times, Serif; text-align: left">&nbsp;</TD></TR>
  </TABLE>


<P STYLE="font: 10pt Times New Roman, Times, Serif; margin: 0pt 0">&nbsp;</P>

<P STYLE="font: 10pt Times New Roman, Times, Serif; margin: 0pt 0; text-align: center"><B>###</B></P>

<P STYLE="font: 10pt Times New Roman, Times, Serif; margin: 0pt 0; text-align: center"><B>&nbsp;</B></P>

<P STYLE="font: 10pt Times New Roman, Times, Serif; margin: 0pt 0"><B>Contact:</B></P>

<P STYLE="font: 10pt Times New Roman, Times, Serif; margin: 0pt 0"><U>mersana@argotpartners.com</U></P>

<P STYLE="font: 10pt Times New Roman, Times, Serif; margin: 0pt 0">&nbsp;</P>

<P STYLE="font: 10pt Times New Roman, Times, Serif; margin: 0pt 0"></P>

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<P STYLE="font: 10pt Times New Roman, Times, Serif; margin: 0pt 0">&nbsp;</P>

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<DOCUMENT>
<TYPE>EX-101.SCH
<SEQUENCE>3
<FILENAME>mrsn-20250813.xsd
<DESCRIPTION>XBRL TAXONOMY EXTENSION SCHEMA
<TEXT>
<XBRL>
<?xml version="1.0" encoding="US-ASCII" ?>
    <!-- Field: Doc-Info; Name: Generator; Value: GoFiler Complete; Version: 6.1a -->
    <!-- Field: Doc-Info; Name: VendorURI; Value: https://www.novaworks.com -->
    <!-- Field: Doc-Info; Name: Status; Value: 0x00000000 -->
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<schema xmlns="http://www.w3.org/2001/XMLSchema" xmlns:xlink="http://www.w3.org/1999/xlink" xmlns:link="http://www.xbrl.org/2003/linkbase" xmlns:xbrli="http://www.xbrl.org/2003/instance" xmlns:xbrldt="http://xbrl.org/2005/xbrldt" xmlns:xbrldi="http://xbrl.org/2006/xbrldi" xmlns:dei="http://xbrl.sec.gov/dei/2025" xmlns:us-gaap="http://fasb.org/us-gaap/2025" xmlns:srt="http://fasb.org/srt/2025" xmlns:srt-types="http://fasb.org/srt-types/2025" xmlns:mrsn="http://mersana.com/20250813" elementFormDefault="qualified" targetNamespace="http://mersana.com/20250813">
    <annotation>
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          <link:definition>00000001 - Document - Cover</link:definition>
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          <link:usedOn>link:calculationLink</link:usedOn>
          <link:usedOn>link:definitionLink</link:usedOn>
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    <import namespace="http://xbrl.sec.gov/dei/2025" schemaLocation="https://xbrl.sec.gov/dei/2025/dei-2025.xsd" />
    <import namespace="http://fasb.org/us-gaap/2025" schemaLocation="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd" />
    <import namespace="http://fasb.org/us-types/2025" schemaLocation="https://xbrl.fasb.org/us-gaap/2025/elts/us-types-2025.xsd" />
    <import namespace="http://www.xbrl.org/dtr/type/2022-03-31" schemaLocation="https://www.xbrl.org/dtr/type/2022-03-31/types.xsd" />
    <import namespace="http://xbrl.sec.gov/country/2025" schemaLocation="https://xbrl.sec.gov/country/2025/country-2025.xsd" />
    <import namespace="http://fasb.org/srt/2025" schemaLocation="https://xbrl.fasb.org/srt/2025/elts/srt-2025.xsd" />
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</schema>
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<DOCUMENT>
<TYPE>EX-101.LAB
<SEQUENCE>4
<FILENAME>mrsn-20250813_lab.xml
<DESCRIPTION>XBRL TAXONOMY EXTENSION LABEL LINKBASE
<TEXT>
<XBRL>
<?xml version="1.0" encoding="US-ASCII" standalone="no"?>
    <!-- Field: Doc-Info; Name: Generator; Value: GoFiler Complete; Version: 6.1a -->
    <!-- Field: Doc-Info; Name: VendorURI; Value: https://www.novaworks.com -->
    <!-- Field: Doc-Info; Name: Status; Value: 0x00000000 -->
<link:linkbase xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xmlns:xlink="http://www.w3.org/1999/xlink" xmlns:link="http://www.xbrl.org/2003/linkbase" xmlns:xbrli="http://www.xbrl.org/2003/instance" xsi:schemaLocation="http://www.xbrl.org/2003/linkbase http://www.xbrl.org/2003/xbrl-linkbase-2003-12-31.xsd">
    <link:roleRef xlink:type="simple" xlink:href="http://www.xbrl.org/lrr/role/negated-2009-12-16.xsd#negatedLabel" roleURI="http://www.xbrl.org/2009/role/negatedLabel" />
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    <link:labelLink xlink:type="extended" xlink:role="http://www.xbrl.org/2003/role/link">
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      <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="dei_CoverAbstract" xlink:to="dei_CoverAbstract_lbl" xlink:type="arc" />
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      <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="dei_DocumentType" xlink:to="dei_DocumentType_lbl" xlink:type="arc" />
      <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="dei_DocumentType_lbl" xml:lang="en-US">Document Type</link:label>
      <link:loc xlink:type="locator" xlink:href="https://xbrl.sec.gov/dei/2025/dei-2025.xsd#dei_AmendmentFlag" xlink:label="dei_AmendmentFlag" />
      <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="dei_AmendmentFlag" xlink:to="dei_AmendmentFlag_lbl" xlink:type="arc" />
      <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="dei_AmendmentFlag_lbl" xml:lang="en-US">Amendment Flag</link:label>
      <link:loc xlink:type="locator" xlink:href="https://xbrl.sec.gov/dei/2025/dei-2025.xsd#dei_AmendmentDescription" xlink:label="dei_AmendmentDescription" />
      <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="dei_AmendmentDescription" xlink:to="dei_AmendmentDescription_lbl" xlink:type="arc" />
      <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="dei_AmendmentDescription_lbl" xml:lang="en-US">Amendment Description</link:label>
      <link:loc xlink:type="locator" xlink:href="https://xbrl.sec.gov/dei/2025/dei-2025.xsd#dei_DocumentRegistrationStatement" xlink:label="dei_DocumentRegistrationStatement" />
      <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="dei_DocumentRegistrationStatement" xlink:to="dei_DocumentRegistrationStatement_lbl" xlink:type="arc" />
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      <link:loc xlink:type="locator" xlink:href="https://xbrl.sec.gov/dei/2025/dei-2025.xsd#dei_DocumentAnnualReport" xlink:label="dei_DocumentAnnualReport" />
      <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="dei_DocumentAnnualReport" xlink:to="dei_DocumentAnnualReport_lbl" xlink:type="arc" />
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      <link:loc xlink:type="locator" xlink:href="https://xbrl.sec.gov/dei/2025/dei-2025.xsd#dei_DocumentQuarterlyReport" xlink:label="dei_DocumentQuarterlyReport" />
      <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="dei_DocumentQuarterlyReport" xlink:to="dei_DocumentQuarterlyReport_lbl" xlink:type="arc" />
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      <link:loc xlink:type="locator" xlink:href="https://xbrl.sec.gov/dei/2025/dei-2025.xsd#dei_DocumentTransitionReport" xlink:label="dei_DocumentTransitionReport" />
      <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="dei_DocumentTransitionReport" xlink:to="dei_DocumentTransitionReport_lbl" xlink:type="arc" />
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      <link:loc xlink:type="locator" xlink:href="https://xbrl.sec.gov/dei/2025/dei-2025.xsd#dei_DocumentShellCompanyReport" xlink:label="dei_DocumentShellCompanyReport" />
      <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="dei_DocumentShellCompanyReport" xlink:to="dei_DocumentShellCompanyReport_lbl" xlink:type="arc" />
      <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="dei_DocumentShellCompanyReport_lbl" xml:lang="en-US">Document Shell Company Report</link:label>
      <link:loc xlink:type="locator" xlink:href="https://xbrl.sec.gov/dei/2025/dei-2025.xsd#dei_DocumentShellCompanyEventDate" xlink:label="dei_DocumentShellCompanyEventDate" />
      <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="dei_DocumentShellCompanyEventDate" xlink:to="dei_DocumentShellCompanyEventDate_lbl" xlink:type="arc" />
      <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="dei_DocumentShellCompanyEventDate_lbl" xml:lang="en-US">Document Shell Company Event Date</link:label>
      <link:loc xlink:type="locator" xlink:href="https://xbrl.sec.gov/dei/2025/dei-2025.xsd#dei_DocumentPeriodStartDate" xlink:label="dei_DocumentPeriodStartDate" />
      <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="dei_DocumentPeriodStartDate" xlink:to="dei_DocumentPeriodStartDate_lbl" xlink:type="arc" />
      <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="dei_DocumentPeriodStartDate_lbl" xml:lang="en-US">Document Period Start Date</link:label>
      <link:loc xlink:type="locator" xlink:href="https://xbrl.sec.gov/dei/2025/dei-2025.xsd#dei_DocumentPeriodEndDate" xlink:label="dei_DocumentPeriodEndDate" />
      <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="dei_DocumentPeriodEndDate" xlink:to="dei_DocumentPeriodEndDate_lbl" xlink:type="arc" />
      <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="dei_DocumentPeriodEndDate_lbl" xml:lang="en-US">Document Period End Date</link:label>
      <link:loc xlink:type="locator" xlink:href="https://xbrl.sec.gov/dei/2025/dei-2025.xsd#dei_DocumentFiscalPeriodFocus" xlink:label="dei_DocumentFiscalPeriodFocus" />
      <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="dei_DocumentFiscalPeriodFocus" xlink:to="dei_DocumentFiscalPeriodFocus_lbl" xlink:type="arc" />
      <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="dei_DocumentFiscalPeriodFocus_lbl" xml:lang="en-US">Document Fiscal Period Focus</link:label>
      <link:loc xlink:type="locator" xlink:href="https://xbrl.sec.gov/dei/2025/dei-2025.xsd#dei_DocumentFiscalYearFocus" xlink:label="dei_DocumentFiscalYearFocus" />
      <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="dei_DocumentFiscalYearFocus" xlink:to="dei_DocumentFiscalYearFocus_lbl" xlink:type="arc" />
      <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="dei_DocumentFiscalYearFocus_lbl" xml:lang="en-US">Document Fiscal Year Focus</link:label>
      <link:loc xlink:type="locator" xlink:href="https://xbrl.sec.gov/dei/2025/dei-2025.xsd#dei_CurrentFiscalYearEndDate" xlink:label="dei_CurrentFiscalYearEndDate" />
      <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="dei_CurrentFiscalYearEndDate" xlink:to="dei_CurrentFiscalYearEndDate_lbl" xlink:type="arc" />
      <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="dei_CurrentFiscalYearEndDate_lbl" xml:lang="en-US">Current Fiscal Year End Date</link:label>
      <link:loc xlink:type="locator" xlink:href="https://xbrl.sec.gov/dei/2025/dei-2025.xsd#dei_EntityFileNumber" xlink:label="dei_EntityFileNumber" />
      <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="dei_EntityFileNumber" xlink:to="dei_EntityFileNumber_lbl" xlink:type="arc" />
      <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="dei_EntityFileNumber_lbl" xml:lang="en-US">Entity File Number</link:label>
      <link:loc xlink:type="locator" xlink:href="https://xbrl.sec.gov/dei/2025/dei-2025.xsd#dei_EntityRegistrantName" xlink:label="dei_EntityRegistrantName" />
      <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="dei_EntityRegistrantName" xlink:to="dei_EntityRegistrantName_lbl" xlink:type="arc" />
      <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="dei_EntityRegistrantName_lbl" xml:lang="en-US">Entity Registrant Name</link:label>
      <link:loc xlink:type="locator" xlink:href="https://xbrl.sec.gov/dei/2025/dei-2025.xsd#dei_EntityCentralIndexKey" xlink:label="dei_EntityCentralIndexKey" />
      <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="dei_EntityCentralIndexKey" xlink:to="dei_EntityCentralIndexKey_lbl" xlink:type="arc" />
      <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="dei_EntityCentralIndexKey_lbl" xml:lang="en-US">Entity Central Index Key</link:label>
      <link:loc xlink:type="locator" xlink:href="https://xbrl.sec.gov/dei/2025/dei-2025.xsd#dei_EntityPrimarySicNumber" xlink:label="dei_EntityPrimarySicNumber" />
      <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="dei_EntityPrimarySicNumber" xlink:to="dei_EntityPrimarySicNumber_lbl" xlink:type="arc" />
      <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="dei_EntityPrimarySicNumber_lbl" xml:lang="en-US">Entity Primary SIC Number</link:label>
      <link:loc xlink:type="locator" xlink:href="https://xbrl.sec.gov/dei/2025/dei-2025.xsd#dei_EntityTaxIdentificationNumber" xlink:label="dei_EntityTaxIdentificationNumber" />
      <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="dei_EntityTaxIdentificationNumber" xlink:to="dei_EntityTaxIdentificationNumber_lbl" xlink:type="arc" />
      <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="dei_EntityTaxIdentificationNumber_lbl" xml:lang="en-US">Entity Tax Identification Number</link:label>
      <link:loc xlink:type="locator" xlink:href="https://xbrl.sec.gov/dei/2025/dei-2025.xsd#dei_EntityIncorporationStateCountryCode" xlink:label="dei_EntityIncorporationStateCountryCode" />
      <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="dei_EntityIncorporationStateCountryCode" xlink:to="dei_EntityIncorporationStateCountryCode_lbl" xlink:type="arc" />
      <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="dei_EntityIncorporationStateCountryCode_lbl" xml:lang="en-US">Entity Incorporation, State or Country Code</link:label>
      <link:loc xlink:type="locator" xlink:href="https://xbrl.sec.gov/dei/2025/dei-2025.xsd#dei_EntityAddressAddressLine1" xlink:label="dei_EntityAddressAddressLine1" />
      <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="dei_EntityAddressAddressLine1" xlink:to="dei_EntityAddressAddressLine1_lbl" xlink:type="arc" />
      <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="dei_EntityAddressAddressLine1_lbl" xml:lang="en-US">Entity Address, Address Line One</link:label>
      <link:loc xlink:type="locator" xlink:href="https://xbrl.sec.gov/dei/2025/dei-2025.xsd#dei_EntityAddressAddressLine2" xlink:label="dei_EntityAddressAddressLine2" />
      <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="dei_EntityAddressAddressLine2" xlink:to="dei_EntityAddressAddressLine2_lbl" xlink:type="arc" />
      <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="dei_EntityAddressAddressLine2_lbl" xml:lang="en-US">Entity Address, Address Line Two</link:label>
      <link:loc xlink:type="locator" xlink:href="https://xbrl.sec.gov/dei/2025/dei-2025.xsd#dei_EntityAddressAddressLine3" xlink:label="dei_EntityAddressAddressLine3" />
      <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="dei_EntityAddressAddressLine3" xlink:to="dei_EntityAddressAddressLine3_lbl" xlink:type="arc" />
      <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="dei_EntityAddressAddressLine3_lbl" xml:lang="en-US">Entity Address, Address Line Three</link:label>
      <link:loc xlink:type="locator" xlink:href="https://xbrl.sec.gov/dei/2025/dei-2025.xsd#dei_EntityAddressCityOrTown" xlink:label="dei_EntityAddressCityOrTown" />
      <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="dei_EntityAddressCityOrTown" xlink:to="dei_EntityAddressCityOrTown_lbl" xlink:type="arc" />
      <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="dei_EntityAddressCityOrTown_lbl" xml:lang="en-US">Entity Address, City or Town</link:label>
      <link:loc xlink:type="locator" xlink:href="https://xbrl.sec.gov/dei/2025/dei-2025.xsd#dei_EntityAddressStateOrProvince" xlink:label="dei_EntityAddressStateOrProvince" />
      <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="dei_EntityAddressStateOrProvince" xlink:to="dei_EntityAddressStateOrProvince_lbl" xlink:type="arc" />
      <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="dei_EntityAddressStateOrProvince_lbl" xml:lang="en-US">Entity Address, State or Province</link:label>
      <link:loc xlink:type="locator" xlink:href="https://xbrl.sec.gov/dei/2025/dei-2025.xsd#dei_EntityAddressCountry" xlink:label="dei_EntityAddressCountry" />
      <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="dei_EntityAddressCountry" xlink:to="dei_EntityAddressCountry_lbl" xlink:type="arc" />
      <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="dei_EntityAddressCountry_lbl" xml:lang="en-US">Entity Address, Country</link:label>
      <link:loc xlink:type="locator" xlink:href="https://xbrl.sec.gov/dei/2025/dei-2025.xsd#dei_EntityAddressPostalZipCode" xlink:label="dei_EntityAddressPostalZipCode" />
      <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="dei_EntityAddressPostalZipCode" xlink:to="dei_EntityAddressPostalZipCode_lbl" xlink:type="arc" />
      <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="dei_EntityAddressPostalZipCode_lbl" xml:lang="en-US">Entity Address, Postal Zip Code</link:label>
      <link:loc xlink:type="locator" xlink:href="https://xbrl.sec.gov/dei/2025/dei-2025.xsd#dei_CountryRegion" xlink:label="dei_CountryRegion" />
      <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="dei_CountryRegion" xlink:to="dei_CountryRegion_lbl" xlink:type="arc" />
      <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="dei_CountryRegion_lbl" xml:lang="en-US">Country Region</link:label>
      <link:loc xlink:type="locator" xlink:href="https://xbrl.sec.gov/dei/2025/dei-2025.xsd#dei_CityAreaCode" xlink:label="dei_CityAreaCode" />
      <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="dei_CityAreaCode" xlink:to="dei_CityAreaCode_lbl" xlink:type="arc" />
      <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="dei_CityAreaCode_lbl" xml:lang="en-US">City Area Code</link:label>
      <link:loc xlink:type="locator" xlink:href="https://xbrl.sec.gov/dei/2025/dei-2025.xsd#dei_LocalPhoneNumber" xlink:label="dei_LocalPhoneNumber" />
      <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="dei_LocalPhoneNumber" xlink:to="dei_LocalPhoneNumber_lbl" xlink:type="arc" />
      <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="dei_LocalPhoneNumber_lbl" xml:lang="en-US">Local Phone Number</link:label>
      <link:loc xlink:type="locator" xlink:href="https://xbrl.sec.gov/dei/2025/dei-2025.xsd#dei_Extension" xlink:label="dei_Extension" />
      <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="dei_Extension" xlink:to="dei_Extension_lbl" xlink:type="arc" />
      <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="dei_Extension_lbl" xml:lang="en-US">Extension</link:label>
      <link:loc xlink:type="locator" xlink:href="https://xbrl.sec.gov/dei/2025/dei-2025.xsd#dei_WrittenCommunications" xlink:label="dei_WrittenCommunications" />
      <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="dei_WrittenCommunications" xlink:to="dei_WrittenCommunications_lbl" xlink:type="arc" />
      <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="dei_WrittenCommunications_lbl" xml:lang="en-US">Written Communications</link:label>
      <link:loc xlink:type="locator" xlink:href="https://xbrl.sec.gov/dei/2025/dei-2025.xsd#dei_SolicitingMaterial" xlink:label="dei_SolicitingMaterial" />
      <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="dei_SolicitingMaterial" xlink:to="dei_SolicitingMaterial_lbl" xlink:type="arc" />
      <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="dei_SolicitingMaterial_lbl" xml:lang="en-US">Soliciting Material</link:label>
      <link:loc xlink:type="locator" xlink:href="https://xbrl.sec.gov/dei/2025/dei-2025.xsd#dei_PreCommencementTenderOffer" xlink:label="dei_PreCommencementTenderOffer" />
      <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="dei_PreCommencementTenderOffer" xlink:to="dei_PreCommencementTenderOffer_lbl" xlink:type="arc" />
      <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="dei_PreCommencementTenderOffer_lbl" xml:lang="en-US">Pre-commencement Tender Offer</link:label>
      <link:loc xlink:type="locator" xlink:href="https://xbrl.sec.gov/dei/2025/dei-2025.xsd#dei_PreCommencementIssuerTenderOffer" xlink:label="dei_PreCommencementIssuerTenderOffer" />
      <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="dei_PreCommencementIssuerTenderOffer" xlink:to="dei_PreCommencementIssuerTenderOffer_lbl" xlink:type="arc" />
      <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="dei_PreCommencementIssuerTenderOffer_lbl" xml:lang="en-US">Pre-commencement Issuer Tender Offer</link:label>
      <link:loc xlink:type="locator" xlink:href="https://xbrl.sec.gov/dei/2025/dei-2025.xsd#dei_Security12bTitle" xlink:label="dei_Security12bTitle" />
      <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="dei_Security12bTitle" xlink:to="dei_Security12bTitle_lbl" xlink:type="arc" />
      <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="dei_Security12bTitle_lbl" xml:lang="en-US">Title of 12(b) Security</link:label>
      <link:loc xlink:type="locator" xlink:href="https://xbrl.sec.gov/dei/2025/dei-2025.xsd#dei_NoTradingSymbolFlag" xlink:label="dei_NoTradingSymbolFlag" />
      <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="dei_NoTradingSymbolFlag" xlink:to="dei_NoTradingSymbolFlag_lbl" xlink:type="arc" />
      <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="dei_NoTradingSymbolFlag_lbl" xml:lang="en-US">No Trading Symbol Flag</link:label>
      <link:loc xlink:type="locator" xlink:href="https://xbrl.sec.gov/dei/2025/dei-2025.xsd#dei_TradingSymbol" xlink:label="dei_TradingSymbol" />
      <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="dei_TradingSymbol" xlink:to="dei_TradingSymbol_lbl" xlink:type="arc" />
      <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="dei_TradingSymbol_lbl" xml:lang="en-US">Trading Symbol</link:label>
      <link:loc xlink:type="locator" xlink:href="https://xbrl.sec.gov/dei/2025/dei-2025.xsd#dei_SecurityExchangeName" xlink:label="dei_SecurityExchangeName" />
      <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="dei_SecurityExchangeName" xlink:to="dei_SecurityExchangeName_lbl" xlink:type="arc" />
      <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="dei_SecurityExchangeName_lbl" xml:lang="en-US">Security Exchange Name</link:label>
      <link:loc xlink:type="locator" xlink:href="https://xbrl.sec.gov/dei/2025/dei-2025.xsd#dei_Security12gTitle" xlink:label="dei_Security12gTitle" />
      <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="dei_Security12gTitle" xlink:to="dei_Security12gTitle_lbl" xlink:type="arc" />
      <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="dei_Security12gTitle_lbl" xml:lang="en-US">Title of 12(g) Security</link:label>
      <link:loc xlink:type="locator" xlink:href="https://xbrl.sec.gov/dei/2025/dei-2025.xsd#dei_SecurityReportingObligation" xlink:label="dei_SecurityReportingObligation" />
      <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="dei_SecurityReportingObligation" xlink:to="dei_SecurityReportingObligation_lbl" xlink:type="arc" />
      <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="dei_SecurityReportingObligation_lbl" xml:lang="en-US">Security Reporting Obligation</link:label>
      <link:loc xlink:type="locator" xlink:href="https://xbrl.sec.gov/dei/2025/dei-2025.xsd#dei_AnnualInformationForm" xlink:label="dei_AnnualInformationForm" />
      <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="dei_AnnualInformationForm" xlink:to="dei_AnnualInformationForm_lbl" xlink:type="arc" />
      <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="dei_AnnualInformationForm_lbl" xml:lang="en-US">Annual Information Form</link:label>
      <link:loc xlink:type="locator" xlink:href="https://xbrl.sec.gov/dei/2025/dei-2025.xsd#dei_AuditedAnnualFinancialStatements" xlink:label="dei_AuditedAnnualFinancialStatements" />
      <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="dei_AuditedAnnualFinancialStatements" xlink:to="dei_AuditedAnnualFinancialStatements_lbl" xlink:type="arc" />
      <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="dei_AuditedAnnualFinancialStatements_lbl" xml:lang="en-US">Audited Annual Financial Statements</link:label>
      <link:loc xlink:type="locator" xlink:href="https://xbrl.sec.gov/dei/2025/dei-2025.xsd#dei_EntityWellKnownSeasonedIssuer" xlink:label="dei_EntityWellKnownSeasonedIssuer" />
      <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="dei_EntityWellKnownSeasonedIssuer" xlink:to="dei_EntityWellKnownSeasonedIssuer_lbl" xlink:type="arc" />
      <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="dei_EntityWellKnownSeasonedIssuer_lbl" xml:lang="en-US">Entity Well-known Seasoned Issuer</link:label>
      <link:loc xlink:type="locator" xlink:href="https://xbrl.sec.gov/dei/2025/dei-2025.xsd#dei_EntityVoluntaryFilers" xlink:label="dei_EntityVoluntaryFilers" />
      <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="dei_EntityVoluntaryFilers" xlink:to="dei_EntityVoluntaryFilers_lbl" xlink:type="arc" />
      <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="dei_EntityVoluntaryFilers_lbl" xml:lang="en-US">Entity Voluntary Filers</link:label>
      <link:loc xlink:type="locator" xlink:href="https://xbrl.sec.gov/dei/2025/dei-2025.xsd#dei_EntityCurrentReportingStatus" xlink:label="dei_EntityCurrentReportingStatus" />
      <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="dei_EntityCurrentReportingStatus" xlink:to="dei_EntityCurrentReportingStatus_lbl" xlink:type="arc" />
      <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="dei_EntityCurrentReportingStatus_lbl" xml:lang="en-US">Entity Current Reporting Status</link:label>
      <link:loc xlink:type="locator" xlink:href="https://xbrl.sec.gov/dei/2025/dei-2025.xsd#dei_EntityInteractiveDataCurrent" xlink:label="dei_EntityInteractiveDataCurrent" />
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<DOCUMENT>
<TYPE>EX-101.PRE
<SEQUENCE>5
<FILENAME>mrsn-20250813_pre.xml
<DESCRIPTION>XBRL TAXONOMY EXTENSION PRESENTATION LINKBASE
<TEXT>
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<TYPE>XML
<SEQUENCE>7
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<DESCRIPTION>IDEA: XBRL DOCUMENT
<TEXT>
<html>
<head>
<title></title>
<link rel="stylesheet" type="text/css" href="include/report.css">
<script type="text/javascript" src="Show.js">/* Do Not Remove This Comment */</script><script type="text/javascript">
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<span style="display: none;">v3.25.2</span><table class="report" border="0" cellspacing="2" id="id2">
<tr>
<th class="tl" colspan="1" rowspan="1"><div style="width: 200px;"><strong>Cover<br></strong></div></th>
<th class="th"><div>Aug. 13, 2025</div></th>
</tr>
<tr class="re">
<td class="pl" style="border-bottom: 0px;" valign="top"><a class="a" href="javascript:void(0);" onclick="Show.showAR( this, 'defref_dei_CoverAbstract', window );"><strong>Cover [Abstract]</strong></a></td>
<td class="text">&#160;<span></span>
</td>
</tr>
<tr class="ro">
<td class="pl" style="border-bottom: 0px;" valign="top"><a class="a" href="javascript:void(0);" onclick="Show.showAR( this, 'defref_dei_DocumentType', window );">Document Type</a></td>
<td class="text">8-K<span></span>
</td>
</tr>
<tr class="re">
<td class="pl" style="border-bottom: 0px;" valign="top"><a class="a" href="javascript:void(0);" onclick="Show.showAR( this, 'defref_dei_AmendmentFlag', window );">Amendment Flag</a></td>
<td class="text">false<span></span>
</td>
</tr>
<tr class="ro">
<td class="pl" style="border-bottom: 0px;" valign="top"><a class="a" href="javascript:void(0);" onclick="Show.showAR( this, 'defref_dei_DocumentPeriodEndDate', window );">Document Period End Date</a></td>
<td class="text">Aug. 13,  2025<span></span>
</td>
</tr>
<tr class="re">
<td class="pl" style="border-bottom: 0px;" valign="top"><a class="a" href="javascript:void(0);" onclick="Show.showAR( this, 'defref_dei_EntityFileNumber', window );">Entity File Number</a></td>
<td class="text">001-38129<span></span>
</td>
</tr>
<tr class="ro">
<td class="pl" style="border-bottom: 0px;" valign="top"><a class="a" href="javascript:void(0);" onclick="Show.showAR( this, 'defref_dei_EntityRegistrantName', window );">Entity Registrant Name</a></td>
<td class="text">MERSANA THERAPEUTICS, INC.<span></span>
</td>
</tr>
<tr class="re">
<td class="pl" style="border-bottom: 0px;" valign="top"><a class="a" href="javascript:void(0);" onclick="Show.showAR( this, 'defref_dei_EntityCentralIndexKey', window );">Entity Central Index Key</a></td>
<td class="text">0001442836<span></span>
</td>
</tr>
<tr class="ro">
<td class="pl" style="border-bottom: 0px;" valign="top"><a class="a" href="javascript:void(0);" onclick="Show.showAR( this, 'defref_dei_EntityTaxIdentificationNumber', window );">Entity Tax Identification Number</a></td>
<td class="text">04-3562403<span></span>
</td>
</tr>
<tr class="re">
<td class="pl" style="border-bottom: 0px;" valign="top"><a class="a" href="javascript:void(0);" onclick="Show.showAR( this, 'defref_dei_EntityIncorporationStateCountryCode', window );">Entity Incorporation, State or Country Code</a></td>
<td class="text">DE<span></span>
</td>
</tr>
<tr class="ro">
<td class="pl" style="border-bottom: 0px;" valign="top"><a class="a" href="javascript:void(0);" onclick="Show.showAR( this, 'defref_dei_EntityAddressAddressLine1', window );">Entity Address, Address Line One</a></td>
<td class="text">840
Memorial Drive<span></span>
</td>
</tr>
<tr class="re">
<td class="pl" style="border-bottom: 0px;" valign="top"><a class="a" href="javascript:void(0);" onclick="Show.showAR( this, 'defref_dei_EntityAddressCityOrTown', window );">Entity Address, City or Town</a></td>
<td class="text">Cambridge<span></span>
</td>
</tr>
<tr class="ro">
<td class="pl" style="border-bottom: 0px;" valign="top"><a class="a" href="javascript:void(0);" onclick="Show.showAR( this, 'defref_dei_EntityAddressStateOrProvince', window );">Entity Address, State or Province</a></td>
<td class="text">MA<span></span>
</td>
</tr>
<tr class="re">
<td class="pl" style="border-bottom: 0px;" valign="top"><a class="a" href="javascript:void(0);" onclick="Show.showAR( this, 'defref_dei_EntityAddressPostalZipCode', window );">Entity Address, Postal Zip Code</a></td>
<td class="text">02139<span></span>
</td>
</tr>
<tr class="ro">
<td class="pl" style="border-bottom: 0px;" valign="top"><a class="a" href="javascript:void(0);" onclick="Show.showAR( this, 'defref_dei_CityAreaCode', window );">City Area Code</a></td>
<td class="text">617<span></span>
</td>
</tr>
<tr class="re">
<td class="pl" style="border-bottom: 0px;" valign="top"><a class="a" href="javascript:void(0);" onclick="Show.showAR( this, 'defref_dei_LocalPhoneNumber', window );">Local Phone Number</a></td>
<td class="text">498-0020<span></span>
</td>
</tr>
<tr class="ro">
<td class="pl" style="border-bottom: 0px;" valign="top"><a class="a" href="javascript:void(0);" onclick="Show.showAR( this, 'defref_dei_WrittenCommunications', window );">Written Communications</a></td>
<td class="text">false<span></span>
</td>
</tr>
<tr class="re">
<td class="pl" style="border-bottom: 0px;" valign="top"><a class="a" href="javascript:void(0);" onclick="Show.showAR( this, 'defref_dei_SolicitingMaterial', window );">Soliciting Material</a></td>
<td class="text">false<span></span>
</td>
</tr>
<tr class="ro">
<td class="pl" style="border-bottom: 0px;" valign="top"><a class="a" href="javascript:void(0);" onclick="Show.showAR( this, 'defref_dei_PreCommencementTenderOffer', window );">Pre-commencement Tender Offer</a></td>
<td class="text">false<span></span>
</td>
</tr>
<tr class="re">
<td class="pl" style="border-bottom: 0px;" valign="top"><a class="a" href="javascript:void(0);" onclick="Show.showAR( this, 'defref_dei_PreCommencementIssuerTenderOffer', window );">Pre-commencement Issuer Tender Offer</a></td>
<td class="text">false<span></span>
</td>
</tr>
<tr class="ro">
<td class="pl" style="border-bottom: 0px;" valign="top"><a class="a" href="javascript:void(0);" onclick="Show.showAR( this, 'defref_dei_Security12bTitle', window );">Title of 12(b) Security</a></td>
<td class="text">Common Stock, $0.0001 par value<span></span>
</td>
</tr>
<tr class="re">
<td class="pl" style="border-bottom: 0px;" valign="top"><a class="a" href="javascript:void(0);" onclick="Show.showAR( this, 'defref_dei_TradingSymbol', window );">Trading Symbol</a></td>
<td class="text">MRSN<span></span>
</td>
</tr>
<tr class="ro">
<td class="pl" style="border-bottom: 0px;" valign="top"><a class="a" href="javascript:void(0);" onclick="Show.showAR( this, 'defref_dei_SecurityExchangeName', window );">Security Exchange Name</a></td>
<td class="text">NASDAQ<span></span>
</td>
</tr>
<tr class="re">
<td class="pl" style="border-bottom: 0px;" valign="top"><a class="a" href="javascript:void(0);" onclick="Show.showAR( this, 'defref_dei_EntityEmergingGrowthCompany', window );">Entity Emerging Growth Company</a></td>
<td class="text">false<span></span>
</td>
</tr>
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<div style="display: none;">
<table border="0" cellpadding="0" cellspacing="0" class="authRefData" style="display: none;" id="defref_dei_AmendmentFlag">
<tr><td class="hide"><a style="color: white;" href="javascript:void(0);" onclick="Show.hideAR();">X</a></td></tr>
<tr><td><div class="body" style="padding: 2px;">
<a href="javascript:void(0);" onclick="Show.toggleNext( this );">- Definition</a><div><p>Boolean flag that is true when the XBRL content amends previously-filed or accepted submission.</p></div>
<a href="javascript:void(0);" onclick="Show.toggleNext( this );">+ References</a><div style="display: none;"><p>No definition available.</p></div>
<a href="javascript:void(0);" onclick="Show.toggleNext( this );">+ Details</a><div style="display: none;"><table border="0" cellpadding="0" cellspacing="0">
<tr>
<td><strong> Name:</strong></td>
<td style="white-space:nowrap;">dei_AmendmentFlag</td>
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<td style="padding-right: 4px;white-space:nowrap;"><strong> Namespace Prefix:</strong></td>
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<td><strong> Data Type:</strong></td>
<td>xbrli:booleanItemType</td>
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<td><strong> Balance Type:</strong></td>
<td>na</td>
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<td><strong> Period Type:</strong></td>
<td>duration</td>
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</table></div>
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<table border="0" cellpadding="0" cellspacing="0" class="authRefData" style="display: none;" id="defref_dei_CityAreaCode">
<tr><td class="hide"><a style="color: white;" href="javascript:void(0);" onclick="Show.hideAR();">X</a></td></tr>
<tr><td><div class="body" style="padding: 2px;">
<a href="javascript:void(0);" onclick="Show.toggleNext( this );">- Definition</a><div><p>Area code of city</p></div>
<a href="javascript:void(0);" onclick="Show.toggleNext( this );">+ References</a><div style="display: none;"><p>No definition available.</p></div>
<a href="javascript:void(0);" onclick="Show.toggleNext( this );">+ Details</a><div style="display: none;"><table border="0" cellpadding="0" cellspacing="0">
<tr>
<td><strong> Name:</strong></td>
<td style="white-space:nowrap;">dei_CityAreaCode</td>
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<tr>
<td style="padding-right: 4px;white-space:nowrap;"><strong> Namespace Prefix:</strong></td>
<td>dei_</td>
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<td><strong> Data Type:</strong></td>
<td>xbrli:normalizedStringItemType</td>
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<td><strong> Balance Type:</strong></td>
<td>na</td>
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<td><strong> Period Type:</strong></td>
<td>duration</td>
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<table border="0" cellpadding="0" cellspacing="0" class="authRefData" style="display: none;" id="defref_dei_CoverAbstract">
<tr><td class="hide"><a style="color: white;" href="javascript:void(0);" onclick="Show.hideAR();">X</a></td></tr>
<tr><td><div class="body" style="padding: 2px;">
<a href="javascript:void(0);" onclick="Show.toggleNext( this );">- Definition</a><div><p>Cover page.</p></div>
<a href="javascript:void(0);" onclick="Show.toggleNext( this );">+ References</a><div style="display: none;"><p>No definition available.</p></div>
<a href="javascript:void(0);" onclick="Show.toggleNext( this );">+ Details</a><div style="display: none;"><table border="0" cellpadding="0" cellspacing="0">
<tr>
<td><strong> Name:</strong></td>
<td style="white-space:nowrap;">dei_CoverAbstract</td>
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<td style="padding-right: 4px;white-space:nowrap;"><strong> Namespace Prefix:</strong></td>
<td>dei_</td>
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<td><strong> Data Type:</strong></td>
<td>xbrli:stringItemType</td>
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<td><strong> Balance Type:</strong></td>
<td>na</td>
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<td><strong> Period Type:</strong></td>
<td>duration</td>
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<table border="0" cellpadding="0" cellspacing="0" class="authRefData" style="display: none;" id="defref_dei_DocumentPeriodEndDate">
<tr><td class="hide"><a style="color: white;" href="javascript:void(0);" onclick="Show.hideAR();">X</a></td></tr>
<tr><td><div class="body" style="padding: 2px;">
<a href="javascript:void(0);" onclick="Show.toggleNext( this );">- Definition</a><div><p>For the EDGAR submission types of Form 8-K: the date of the report, the date of the earliest event reported; for the EDGAR submission types of Form N-1A: the filing date; for all other submission types: the end of the reporting or transition period. The format of the date is YYYY-MM-DD.</p></div>
<a href="javascript:void(0);" onclick="Show.toggleNext( this );">+ References</a><div style="display: none;"><p>No definition available.</p></div>
<a href="javascript:void(0);" onclick="Show.toggleNext( this );">+ Details</a><div style="display: none;"><table border="0" cellpadding="0" cellspacing="0">
<tr>
<td><strong> Name:</strong></td>
<td style="white-space:nowrap;">dei_DocumentPeriodEndDate</td>
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<td style="padding-right: 4px;white-space:nowrap;"><strong> Namespace Prefix:</strong></td>
<td>dei_</td>
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<td><strong> Data Type:</strong></td>
<td>xbrli:dateItemType</td>
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<td><strong> Balance Type:</strong></td>
<td>na</td>
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<td><strong> Period Type:</strong></td>
<td>duration</td>
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<tr><td class="hide"><a style="color: white;" href="javascript:void(0);" onclick="Show.hideAR();">X</a></td></tr>
<tr><td><div class="body" style="padding: 2px;">
<a href="javascript:void(0);" onclick="Show.toggleNext( this );">- Definition</a><div><p>The type of document being provided (such as 10-K, 10-Q, 485BPOS, etc). The document type is limited to the same value as the supporting SEC submission type, or the word 'Other'.</p></div>
<a href="javascript:void(0);" onclick="Show.toggleNext( this );">+ References</a><div style="display: none;"><p>No definition available.</p></div>
<a href="javascript:void(0);" onclick="Show.toggleNext( this );">+ Details</a><div style="display: none;"><table border="0" cellpadding="0" cellspacing="0">
<tr>
<td><strong> Name:</strong></td>
<td style="white-space:nowrap;">dei_DocumentType</td>
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<td style="padding-right: 4px;white-space:nowrap;"><strong> Namespace Prefix:</strong></td>
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<td><strong> Data Type:</strong></td>
<td>dei:submissionTypeItemType</td>
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<td><strong> Balance Type:</strong></td>
<td>na</td>
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<td><strong> Period Type:</strong></td>
<td>duration</td>
</tr>
</table></div>
</div></td></tr>
</table>
<table border="0" cellpadding="0" cellspacing="0" class="authRefData" style="display: none;" id="defref_dei_EntityAddressAddressLine1">
<tr><td class="hide"><a style="color: white;" href="javascript:void(0);" onclick="Show.hideAR();">X</a></td></tr>
<tr><td><div class="body" style="padding: 2px;">
<a href="javascript:void(0);" onclick="Show.toggleNext( this );">- Definition</a><div><p>Address Line 1 such as Attn, Building Name, Street Name</p></div>
<a href="javascript:void(0);" onclick="Show.toggleNext( this );">+ References</a><div style="display: none;"><p>No definition available.</p></div>
<a href="javascript:void(0);" onclick="Show.toggleNext( this );">+ Details</a><div style="display: none;"><table border="0" cellpadding="0" cellspacing="0">
<tr>
<td><strong> Name:</strong></td>
<td style="white-space:nowrap;">dei_EntityAddressAddressLine1</td>
</tr>
<tr>
<td style="padding-right: 4px;white-space:nowrap;"><strong> Namespace Prefix:</strong></td>
<td>dei_</td>
</tr>
<tr>
<td><strong> Data Type:</strong></td>
<td>xbrli:normalizedStringItemType</td>
</tr>
<tr>
<td><strong> Balance Type:</strong></td>
<td>na</td>
</tr>
<tr>
<td><strong> Period Type:</strong></td>
<td>duration</td>
</tr>
</table></div>
</div></td></tr>
</table>
<table border="0" cellpadding="0" cellspacing="0" class="authRefData" style="display: none;" id="defref_dei_EntityAddressCityOrTown">
<tr><td class="hide"><a style="color: white;" href="javascript:void(0);" onclick="Show.hideAR();">X</a></td></tr>
<tr><td><div class="body" style="padding: 2px;">
<a href="javascript:void(0);" onclick="Show.toggleNext( this );">- Definition</a><div><p>Name of the City or Town</p></div>
<a href="javascript:void(0);" onclick="Show.toggleNext( this );">+ References</a><div style="display: none;"><p>No definition available.</p></div>
<a href="javascript:void(0);" onclick="Show.toggleNext( this );">+ Details</a><div style="display: none;"><table border="0" cellpadding="0" cellspacing="0">
<tr>
<td><strong> Name:</strong></td>
<td style="white-space:nowrap;">dei_EntityAddressCityOrTown</td>
</tr>
<tr>
<td style="padding-right: 4px;white-space:nowrap;"><strong> Namespace Prefix:</strong></td>
<td>dei_</td>
</tr>
<tr>
<td><strong> Data Type:</strong></td>
<td>xbrli:normalizedStringItemType</td>
</tr>
<tr>
<td><strong> Balance Type:</strong></td>
<td>na</td>
</tr>
<tr>
<td><strong> Period Type:</strong></td>
<td>duration</td>
</tr>
</table></div>
</div></td></tr>
</table>
<table border="0" cellpadding="0" cellspacing="0" class="authRefData" style="display: none;" id="defref_dei_EntityAddressPostalZipCode">
<tr><td class="hide"><a style="color: white;" href="javascript:void(0);" onclick="Show.hideAR();">X</a></td></tr>
<tr><td><div class="body" style="padding: 2px;">
<a href="javascript:void(0);" onclick="Show.toggleNext( this );">- Definition</a><div><p>Code for the postal or zip code</p></div>
<a href="javascript:void(0);" onclick="Show.toggleNext( this );">+ References</a><div style="display: none;"><p>No definition available.</p></div>
<a href="javascript:void(0);" onclick="Show.toggleNext( this );">+ Details</a><div style="display: none;"><table border="0" cellpadding="0" cellspacing="0">
<tr>
<td><strong> Name:</strong></td>
<td style="white-space:nowrap;">dei_EntityAddressPostalZipCode</td>
</tr>
<tr>
<td style="padding-right: 4px;white-space:nowrap;"><strong> Namespace Prefix:</strong></td>
<td>dei_</td>
</tr>
<tr>
<td><strong> Data Type:</strong></td>
<td>xbrli:normalizedStringItemType</td>
</tr>
<tr>
<td><strong> Balance Type:</strong></td>
<td>na</td>
</tr>
<tr>
<td><strong> Period Type:</strong></td>
<td>duration</td>
</tr>
</table></div>
</div></td></tr>
</table>
<table border="0" cellpadding="0" cellspacing="0" class="authRefData" style="display: none;" id="defref_dei_EntityAddressStateOrProvince">
<tr><td class="hide"><a style="color: white;" href="javascript:void(0);" onclick="Show.hideAR();">X</a></td></tr>
<tr><td><div class="body" style="padding: 2px;">
<a href="javascript:void(0);" onclick="Show.toggleNext( this );">- Definition</a><div><p>Name of the state or province.</p></div>
<a href="javascript:void(0);" onclick="Show.toggleNext( this );">+ References</a><div style="display: none;"><p>No definition available.</p></div>
<a href="javascript:void(0);" onclick="Show.toggleNext( this );">+ Details</a><div style="display: none;"><table border="0" cellpadding="0" cellspacing="0">
<tr>
<td><strong> Name:</strong></td>
<td style="white-space:nowrap;">dei_EntityAddressStateOrProvince</td>
</tr>
<tr>
<td style="padding-right: 4px;white-space:nowrap;"><strong> Namespace Prefix:</strong></td>
<td>dei_</td>
</tr>
<tr>
<td><strong> Data Type:</strong></td>
<td>dei:stateOrProvinceItemType</td>
</tr>
<tr>
<td><strong> Balance Type:</strong></td>
<td>na</td>
</tr>
<tr>
<td><strong> Period Type:</strong></td>
<td>duration</td>
</tr>
</table></div>
</div></td></tr>
</table>
<table border="0" cellpadding="0" cellspacing="0" class="authRefData" style="display: none;" id="defref_dei_EntityCentralIndexKey">
<tr><td class="hide"><a style="color: white;" href="javascript:void(0);" onclick="Show.hideAR();">X</a></td></tr>
<tr><td><div class="body" style="padding: 2px;">
<a href="javascript:void(0);" onclick="Show.toggleNext( this );">- Definition</a><div><p>A unique 10-digit SEC-issued value to identify entities that have filed disclosures with the SEC. It is commonly abbreviated as CIK.</p></div>
<a href="javascript:void(0);" onclick="Show.toggleNext( this );">+ References</a><div style="display: none;"><p>Reference 1: http://www.xbrl.org/2003/role/presentationRef<br> -Publisher SEC<br> -Name Exchange Act<br> -Number 240<br> -Section 12<br> -Subsection b-2<br></p></div>
<a href="javascript:void(0);" onclick="Show.toggleNext( this );">+ Details</a><div style="display: none;"><table border="0" cellpadding="0" cellspacing="0">
<tr>
<td><strong> Name:</strong></td>
<td style="white-space:nowrap;">dei_EntityCentralIndexKey</td>
</tr>
<tr>
<td style="padding-right: 4px;white-space:nowrap;"><strong> Namespace Prefix:</strong></td>
<td>dei_</td>
</tr>
<tr>
<td><strong> Data Type:</strong></td>
<td>dei:centralIndexKeyItemType</td>
</tr>
<tr>
<td><strong> Balance Type:</strong></td>
<td>na</td>
</tr>
<tr>
<td><strong> Period Type:</strong></td>
<td>duration</td>
</tr>
</table></div>
</div></td></tr>
</table>
<table border="0" cellpadding="0" cellspacing="0" class="authRefData" style="display: none;" id="defref_dei_EntityEmergingGrowthCompany">
<tr><td class="hide"><a style="color: white;" href="javascript:void(0);" onclick="Show.hideAR();">X</a></td></tr>
<tr><td><div class="body" style="padding: 2px;">
<a href="javascript:void(0);" onclick="Show.toggleNext( this );">- Definition</a><div><p>Indicate if registrant meets the emerging growth company criteria.</p></div>
<a href="javascript:void(0);" onclick="Show.toggleNext( this );">+ References</a><div style="display: none;"><p>Reference 1: http://www.xbrl.org/2003/role/presentationRef<br> -Publisher SEC<br> -Name Exchange Act<br> -Number 240<br> -Section 12<br> -Subsection b-2<br></p></div>
<a href="javascript:void(0);" onclick="Show.toggleNext( this );">+ Details</a><div style="display: none;"><table border="0" cellpadding="0" cellspacing="0">
<tr>
<td><strong> Name:</strong></td>
<td style="white-space:nowrap;">dei_EntityEmergingGrowthCompany</td>
</tr>
<tr>
<td style="padding-right: 4px;white-space:nowrap;"><strong> Namespace Prefix:</strong></td>
<td>dei_</td>
</tr>
<tr>
<td><strong> Data Type:</strong></td>
<td>xbrli:booleanItemType</td>
</tr>
<tr>
<td><strong> Balance Type:</strong></td>
<td>na</td>
</tr>
<tr>
<td><strong> Period Type:</strong></td>
<td>duration</td>
</tr>
</table></div>
</div></td></tr>
</table>
<table border="0" cellpadding="0" cellspacing="0" class="authRefData" style="display: none;" id="defref_dei_EntityFileNumber">
<tr><td class="hide"><a style="color: white;" href="javascript:void(0);" onclick="Show.hideAR();">X</a></td></tr>
<tr><td><div class="body" style="padding: 2px;">
<a href="javascript:void(0);" onclick="Show.toggleNext( this );">- Definition</a><div><p>Commission file number. The field allows up to 17 characters. The prefix may contain 1-3 digits, the sequence number may contain 1-8 digits, the optional suffix may contain 1-4 characters, and the fields are separated with a hyphen.</p></div>
<a href="javascript:void(0);" onclick="Show.toggleNext( this );">+ References</a><div style="display: none;"><p>No definition available.</p></div>
<a href="javascript:void(0);" onclick="Show.toggleNext( this );">+ Details</a><div style="display: none;"><table border="0" cellpadding="0" cellspacing="0">
<tr>
<td><strong> Name:</strong></td>
<td style="white-space:nowrap;">dei_EntityFileNumber</td>
</tr>
<tr>
<td style="padding-right: 4px;white-space:nowrap;"><strong> Namespace Prefix:</strong></td>
<td>dei_</td>
</tr>
<tr>
<td><strong> Data Type:</strong></td>
<td>dei:fileNumberItemType</td>
</tr>
<tr>
<td><strong> Balance Type:</strong></td>
<td>na</td>
</tr>
<tr>
<td><strong> Period Type:</strong></td>
<td>duration</td>
</tr>
</table></div>
</div></td></tr>
</table>
<table border="0" cellpadding="0" cellspacing="0" class="authRefData" style="display: none;" id="defref_dei_EntityIncorporationStateCountryCode">
<tr><td class="hide"><a style="color: white;" href="javascript:void(0);" onclick="Show.hideAR();">X</a></td></tr>
<tr><td><div class="body" style="padding: 2px;">
<a href="javascript:void(0);" onclick="Show.toggleNext( this );">- Definition</a><div><p>Two-character EDGAR code representing the state or country of incorporation.</p></div>
<a href="javascript:void(0);" onclick="Show.toggleNext( this );">+ References</a><div style="display: none;"><p>No definition available.</p></div>
<a href="javascript:void(0);" onclick="Show.toggleNext( this );">+ Details</a><div style="display: none;"><table border="0" cellpadding="0" cellspacing="0">
<tr>
<td><strong> Name:</strong></td>
<td style="white-space:nowrap;">dei_EntityIncorporationStateCountryCode</td>
</tr>
<tr>
<td style="padding-right: 4px;white-space:nowrap;"><strong> Namespace Prefix:</strong></td>
<td>dei_</td>
</tr>
<tr>
<td><strong> Data Type:</strong></td>
<td>dei:edgarStateCountryItemType</td>
</tr>
<tr>
<td><strong> Balance Type:</strong></td>
<td>na</td>
</tr>
<tr>
<td><strong> Period Type:</strong></td>
<td>duration</td>
</tr>
</table></div>
</div></td></tr>
</table>
<table border="0" cellpadding="0" cellspacing="0" class="authRefData" style="display: none;" id="defref_dei_EntityRegistrantName">
<tr><td class="hide"><a style="color: white;" href="javascript:void(0);" onclick="Show.hideAR();">X</a></td></tr>
<tr><td><div class="body" style="padding: 2px;">
<a href="javascript:void(0);" onclick="Show.toggleNext( this );">- Definition</a><div><p>The exact name of the entity filing the report as specified in its charter, which is required by forms filed with the SEC.</p></div>
<a href="javascript:void(0);" onclick="Show.toggleNext( this );">+ References</a><div style="display: none;"><p>Reference 1: http://www.xbrl.org/2003/role/presentationRef<br> -Publisher SEC<br> -Name Exchange Act<br> -Number 240<br> -Section 12<br> -Subsection b-2<br></p></div>
<a href="javascript:void(0);" onclick="Show.toggleNext( this );">+ Details</a><div style="display: none;"><table border="0" cellpadding="0" cellspacing="0">
<tr>
<td><strong> Name:</strong></td>
<td style="white-space:nowrap;">dei_EntityRegistrantName</td>
</tr>
<tr>
<td style="padding-right: 4px;white-space:nowrap;"><strong> Namespace Prefix:</strong></td>
<td>dei_</td>
</tr>
<tr>
<td><strong> Data Type:</strong></td>
<td>xbrli:normalizedStringItemType</td>
</tr>
<tr>
<td><strong> Balance Type:</strong></td>
<td>na</td>
</tr>
<tr>
<td><strong> Period Type:</strong></td>
<td>duration</td>
</tr>
</table></div>
</div></td></tr>
</table>
<table border="0" cellpadding="0" cellspacing="0" class="authRefData" style="display: none;" id="defref_dei_EntityTaxIdentificationNumber">
<tr><td class="hide"><a style="color: white;" href="javascript:void(0);" onclick="Show.hideAR();">X</a></td></tr>
<tr><td><div class="body" style="padding: 2px;">
<a href="javascript:void(0);" onclick="Show.toggleNext( this );">- Definition</a><div><p>The Tax Identification Number (TIN), also known as an Employer Identification Number (EIN), is a unique 9-digit value assigned by the IRS.</p></div>
<a href="javascript:void(0);" onclick="Show.toggleNext( this );">+ References</a><div style="display: none;"><p>Reference 1: http://www.xbrl.org/2003/role/presentationRef<br> -Publisher SEC<br> -Name Exchange Act<br> -Number 240<br> -Section 12<br> -Subsection b-2<br></p></div>
<a href="javascript:void(0);" onclick="Show.toggleNext( this );">+ Details</a><div style="display: none;"><table border="0" cellpadding="0" cellspacing="0">
<tr>
<td><strong> Name:</strong></td>
<td style="white-space:nowrap;">dei_EntityTaxIdentificationNumber</td>
</tr>
<tr>
<td style="padding-right: 4px;white-space:nowrap;"><strong> Namespace Prefix:</strong></td>
<td>dei_</td>
</tr>
<tr>
<td><strong> Data Type:</strong></td>
<td>dei:employerIdItemType</td>
</tr>
<tr>
<td><strong> Balance Type:</strong></td>
<td>na</td>
</tr>
<tr>
<td><strong> Period Type:</strong></td>
<td>duration</td>
</tr>
</table></div>
</div></td></tr>
</table>
<table border="0" cellpadding="0" cellspacing="0" class="authRefData" style="display: none;" id="defref_dei_LocalPhoneNumber">
<tr><td class="hide"><a style="color: white;" href="javascript:void(0);" onclick="Show.hideAR();">X</a></td></tr>
<tr><td><div class="body" style="padding: 2px;">
<a href="javascript:void(0);" onclick="Show.toggleNext( this );">- Definition</a><div><p>Local phone number for entity.</p></div>
<a href="javascript:void(0);" onclick="Show.toggleNext( this );">+ References</a><div style="display: none;"><p>No definition available.</p></div>
<a href="javascript:void(0);" onclick="Show.toggleNext( this );">+ Details</a><div style="display: none;"><table border="0" cellpadding="0" cellspacing="0">
<tr>
<td><strong> Name:</strong></td>
<td style="white-space:nowrap;">dei_LocalPhoneNumber</td>
</tr>
<tr>
<td style="padding-right: 4px;white-space:nowrap;"><strong> Namespace Prefix:</strong></td>
<td>dei_</td>
</tr>
<tr>
<td><strong> Data Type:</strong></td>
<td>xbrli:normalizedStringItemType</td>
</tr>
<tr>
<td><strong> Balance Type:</strong></td>
<td>na</td>
</tr>
<tr>
<td><strong> Period Type:</strong></td>
<td>duration</td>
</tr>
</table></div>
</div></td></tr>
</table>
<table border="0" cellpadding="0" cellspacing="0" class="authRefData" style="display: none;" id="defref_dei_PreCommencementIssuerTenderOffer">
<tr><td class="hide"><a style="color: white;" href="javascript:void(0);" onclick="Show.hideAR();">X</a></td></tr>
<tr><td><div class="body" style="padding: 2px;">
<a href="javascript:void(0);" onclick="Show.toggleNext( this );">- Definition</a><div><p>Boolean flag that is true when the Form 8-K filing is intended to satisfy the filing obligation of the registrant as pre-commencement communications pursuant to Rule 13e-4(c) under the Exchange Act.</p></div>
<a href="javascript:void(0);" onclick="Show.toggleNext( this );">+ References</a><div style="display: none;"><p>Reference 1: http://www.xbrl.org/2003/role/presentationRef<br> -Publisher SEC<br> -Name Exchange Act<br> -Number 240<br> -Section 13e<br> -Subsection 4c<br></p></div>
<a href="javascript:void(0);" onclick="Show.toggleNext( this );">+ Details</a><div style="display: none;"><table border="0" cellpadding="0" cellspacing="0">
<tr>
<td><strong> Name:</strong></td>
<td style="white-space:nowrap;">dei_PreCommencementIssuerTenderOffer</td>
</tr>
<tr>
<td style="padding-right: 4px;white-space:nowrap;"><strong> Namespace Prefix:</strong></td>
<td>dei_</td>
</tr>
<tr>
<td><strong> Data Type:</strong></td>
<td>xbrli:booleanItemType</td>
</tr>
<tr>
<td><strong> Balance Type:</strong></td>
<td>na</td>
</tr>
<tr>
<td><strong> Period Type:</strong></td>
<td>duration</td>
</tr>
</table></div>
</div></td></tr>
</table>
<table border="0" cellpadding="0" cellspacing="0" class="authRefData" style="display: none;" id="defref_dei_PreCommencementTenderOffer">
<tr><td class="hide"><a style="color: white;" href="javascript:void(0);" onclick="Show.hideAR();">X</a></td></tr>
<tr><td><div class="body" style="padding: 2px;">
<a href="javascript:void(0);" onclick="Show.toggleNext( this );">- Definition</a><div><p>Boolean flag that is true when the Form 8-K filing is intended to satisfy the filing obligation of the registrant as pre-commencement communications pursuant to Rule 14d-2(b) under the Exchange Act.</p></div>
<a href="javascript:void(0);" onclick="Show.toggleNext( this );">+ References</a><div style="display: none;"><p>Reference 1: http://www.xbrl.org/2003/role/presentationRef<br> -Publisher SEC<br> -Name Exchange Act<br> -Number 240<br> -Section 14d<br> -Subsection 2b<br></p></div>
<a href="javascript:void(0);" onclick="Show.toggleNext( this );">+ Details</a><div style="display: none;"><table border="0" cellpadding="0" cellspacing="0">
<tr>
<td><strong> Name:</strong></td>
<td style="white-space:nowrap;">dei_PreCommencementTenderOffer</td>
</tr>
<tr>
<td style="padding-right: 4px;white-space:nowrap;"><strong> Namespace Prefix:</strong></td>
<td>dei_</td>
</tr>
<tr>
<td><strong> Data Type:</strong></td>
<td>xbrli:booleanItemType</td>
</tr>
<tr>
<td><strong> Balance Type:</strong></td>
<td>na</td>
</tr>
<tr>
<td><strong> Period Type:</strong></td>
<td>duration</td>
</tr>
</table></div>
</div></td></tr>
</table>
<table border="0" cellpadding="0" cellspacing="0" class="authRefData" style="display: none;" id="defref_dei_Security12bTitle">
<tr><td class="hide"><a style="color: white;" href="javascript:void(0);" onclick="Show.hideAR();">X</a></td></tr>
<tr><td><div class="body" style="padding: 2px;">
<a href="javascript:void(0);" onclick="Show.toggleNext( this );">- Definition</a><div><p>Title of a 12(b) registered security.</p></div>
<a href="javascript:void(0);" onclick="Show.toggleNext( this );">+ References</a><div style="display: none;"><p>Reference 1: http://www.xbrl.org/2003/role/presentationRef<br> -Publisher SEC<br> -Name Exchange Act<br> -Number 240<br> -Section 12<br> -Subsection b<br></p></div>
<a href="javascript:void(0);" onclick="Show.toggleNext( this );">+ Details</a><div style="display: none;"><table border="0" cellpadding="0" cellspacing="0">
<tr>
<td><strong> Name:</strong></td>
<td style="white-space:nowrap;">dei_Security12bTitle</td>
</tr>
<tr>
<td style="padding-right: 4px;white-space:nowrap;"><strong> Namespace Prefix:</strong></td>
<td>dei_</td>
</tr>
<tr>
<td><strong> Data Type:</strong></td>
<td>dei:securityTitleItemType</td>
</tr>
<tr>
<td><strong> Balance Type:</strong></td>
<td>na</td>
</tr>
<tr>
<td><strong> Period Type:</strong></td>
<td>duration</td>
</tr>
</table></div>
</div></td></tr>
</table>
<table border="0" cellpadding="0" cellspacing="0" class="authRefData" style="display: none;" id="defref_dei_SecurityExchangeName">
<tr><td class="hide"><a style="color: white;" href="javascript:void(0);" onclick="Show.hideAR();">X</a></td></tr>
<tr><td><div class="body" style="padding: 2px;">
<a href="javascript:void(0);" onclick="Show.toggleNext( this );">- Definition</a><div><p>Name of the Exchange on which a security is registered.</p></div>
<a href="javascript:void(0);" onclick="Show.toggleNext( this );">+ References</a><div style="display: none;"><p>Reference 1: http://www.xbrl.org/2003/role/presentationRef<br> -Publisher SEC<br> -Name Exchange Act<br> -Number 240<br> -Section 12<br> -Subsection d1-1<br></p></div>
<a href="javascript:void(0);" onclick="Show.toggleNext( this );">+ Details</a><div style="display: none;"><table border="0" cellpadding="0" cellspacing="0">
<tr>
<td><strong> Name:</strong></td>
<td style="white-space:nowrap;">dei_SecurityExchangeName</td>
</tr>
<tr>
<td style="padding-right: 4px;white-space:nowrap;"><strong> Namespace Prefix:</strong></td>
<td>dei_</td>
</tr>
<tr>
<td><strong> Data Type:</strong></td>
<td>dei:edgarExchangeCodeItemType</td>
</tr>
<tr>
<td><strong> Balance Type:</strong></td>
<td>na</td>
</tr>
<tr>
<td><strong> Period Type:</strong></td>
<td>duration</td>
</tr>
</table></div>
</div></td></tr>
</table>
<table border="0" cellpadding="0" cellspacing="0" class="authRefData" style="display: none;" id="defref_dei_SolicitingMaterial">
<tr><td class="hide"><a style="color: white;" href="javascript:void(0);" onclick="Show.hideAR();">X</a></td></tr>
<tr><td><div class="body" style="padding: 2px;">
<a href="javascript:void(0);" onclick="Show.toggleNext( this );">- Definition</a><div><p>Boolean flag that is true when the Form 8-K filing is intended to satisfy the filing obligation of the registrant as soliciting material pursuant to Rule 14a-12 under the Exchange Act.</p></div>
<a href="javascript:void(0);" onclick="Show.toggleNext( this );">+ References</a><div style="display: none;"><p>Reference 1: http://www.xbrl.org/2003/role/presentationRef<br> -Publisher SEC<br> -Name Exchange Act<br> -Number 240<br> -Section 14a<br> -Subsection 12<br></p></div>
<a href="javascript:void(0);" onclick="Show.toggleNext( this );">+ Details</a><div style="display: none;"><table border="0" cellpadding="0" cellspacing="0">
<tr>
<td><strong> Name:</strong></td>
<td style="white-space:nowrap;">dei_SolicitingMaterial</td>
</tr>
<tr>
<td style="padding-right: 4px;white-space:nowrap;"><strong> Namespace Prefix:</strong></td>
<td>dei_</td>
</tr>
<tr>
<td><strong> Data Type:</strong></td>
<td>xbrli:booleanItemType</td>
</tr>
<tr>
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