    <SEC-DOCUMENT>0001104659-21-054580-index.html : 20210426
    <SEC-HEADER>0001104659-21-054580.hdr.sgml : 20210426
    <ACCEPTANCE-DATETIME>20210423180231
    ACCESSION NUMBER:		0001104659-21-054580
    CONFORMED SUBMISSION TYPE:	DEFA14A
    PUBLIC DOCUMENT COUNT:		3
    FILED AS OF DATE:		20210426
    DATE AS OF CHANGE:		20210423

    FILER:

    	COMPANY DATA:
    		COMPANY CONFORMED NAME:			SELLAS Life Sciences Group, Inc.
    		CENTRAL INDEX KEY:			0001390478
    		STANDARD INDUSTRIAL CLASSIFICATION:	PHARMACEUTICAL PREPARATIONS [2834]
    		IRS NUMBER:				000000000
    		STATE OF INCORPORATION:			DE
    		FISCAL YEAR END:			1231

    	FILING VALUES:
    		FORM TYPE:		DEFA14A
    		SEC ACT:		1934 Act
    		SEC FILE NUMBER:	001-33958
    		FILM NUMBER:		21850871

    	BUSINESS ADDRESS:
    		STREET 1:		7 TIMES SQUARE
    		STREET 2:		SUITE 2503
    		CITY:			NEW YORK
    		STATE:			NY
    		ZIP:			10036
    		BUSINESS PHONE:		6462005278

    	MAIL ADDRESS:
    		STREET 1:		7 TIMES SQUARE
    		STREET 2:		SUITE 2503
    		CITY:			NEW YORK
    		STATE:			NY
    		ZIP:			10036

    	FORMER COMPANY:
    		FORMER CONFORMED NAME:	Galena Biopharma, Inc.
    		DATE OF NAME CHANGE:	20110926

    	FORMER COMPANY:
    		FORMER CONFORMED NAME:	RXi Pharmaceuticals Corp
    		DATE OF NAME CHANGE:	20110926

    	FORMER COMPANY:
    		FORMER CONFORMED NAME:	GALENA BIOPHARMA, INC.
    		DATE OF NAME CHANGE:	20110922
    </SEC-HEADER>
    <DOCUMENT>
    <TYPE>DEFA14A
    <SEQUENCE>1
    <FILENAME>tm2113795d2_defa14a.htm
    <DESCRIPTION>DEFA14A
    <TEXT>
    Document 1 - file: tm2113795d2_defa14a.htm

    </DOCUMENT>
    <DOCUMENT>
    <TYPE>GRAPHIC
    <SEQUENCE>2
    <FILENAME>image_001.jpg
    <DESCRIPTION>GRAPHIC
    <TEXT>
    Document 2 - file: image_001.jpg

    </DOCUMENT>
    <DOCUMENT>
    <TYPE>GRAPHIC
    <SEQUENCE>3
    <FILENAME>image_002.jpg
    <DESCRIPTION>GRAPHIC
    <TEXT>
    Document 3 - file: image_002.jpg

    </DOCUMENT>
    </SEC-DOCUMENT>