<SEC-DOCUMENT>0000947871-23-000180-index.html : 20230214
<SEC-HEADER>0000947871-23-000180.hdr.sgml : 20230214
<ACCEPTANCE-DATETIME>20230214164321
ACCESSION NUMBER:		0000947871-23-000180
CONFORMED SUBMISSION TYPE:	SC 13G
PUBLIC DOCUMENT COUNT:		2
FILED AS OF DATE:		20230214
DATE AS OF CHANGE:		20230214
GROUP MEMBERS:		ORBIMED CAPITAL LLC

SUBJECT COMPANY:	

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

	FILING VALUES:
		FORM TYPE:		SC 13G
		SEC ACT:		1934 Act
		SEC FILE NUMBER:	005-90033
		FILM NUMBER:		23630656

	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

FILED BY:		

	COMPANY DATA:	
		COMPANY CONFORMED NAME:			ORBIMED ADVISORS LLC
		CENTRAL INDEX KEY:			0001055951
		IRS NUMBER:				133976876
		STATE OF INCORPORATION:			DE

	FILING VALUES:
		FORM TYPE:		SC 13G

	BUSINESS ADDRESS:	
		STREET 1:		601 LEXINGTON AVENUE
		STREET 2:		54TH FLOOR
		CITY:			NEW YORK
		STATE:			NY
		ZIP:			10022
		BUSINESS PHONE:		(212) 739-6400

	MAIL ADDRESS:	
		STREET 1:		601 LEXINGTON AVENUE
		STREET 2:		54TH FLOOR
		CITY:			NEW YORK
		STATE:			NY
		ZIP:			10022
</SEC-HEADER>
<DOCUMENT>
<TYPE>SC 13G
<SEQUENCE>1
<FILENAME>ss1758599_sc13g.htm
<DESCRIPTION>SCHEDULE 13G
<TEXT>
Document 1 - file: ss1758599_sc13g.htm

</DOCUMENT>
<DOCUMENT>
<TYPE>EX-99.A
<SEQUENCE>2
<FILENAME>ss1758599_ex99a.htm
<DESCRIPTION>JOINT FILING AGREEMENT
<TEXT>
Document 2 - file: ss1758599_ex99a.htm

</DOCUMENT>
</SEC-DOCUMENT>