<SEC-DOCUMENT>9999999995-13-001808.txt : 20130617
<SEC-HEADER>9999999995-13-001808.hdr.sgml : 20130617
<ACCEPTANCE-DATETIME>20130617001930
ACCESSION NUMBER:		9999999995-13-001808
CONFORMED SUBMISSION TYPE:	EFFECT
PUBLIC DOCUMENT COUNT:		1
FILED AS OF DATE:		20130614
DATE AS OF CHANGE:		20130617
EFFECTIVENESS DATE:		20130614

FILER:

	COMPANY DATA:	
		COMPANY CONFORMED NAME:			Mast Therapeutics, Inc.
		CENTRAL INDEX KEY:			0001160308
		STANDARD INDUSTRIAL CLASSIFICATION:	PHARMACEUTICAL PREPARATIONS [2834]
		IRS NUMBER:				841318182
		STATE OF INCORPORATION:			DE
		FISCAL YEAR END:			1231

	FILING VALUES:
		FORM TYPE:		EFFECT
		SEC ACT:		1933 Act
		SEC FILE NUMBER:	333-188870
		FILM NUMBER:		13915539

	BUSINESS ADDRESS:	
		STREET 1:		12390 EL CAMINO REAL
		STREET 2:		SUITE 150
		CITY:			SAN DIEGO
		STATE:			CA
		ZIP:			92130
		BUSINESS PHONE:		8585520866

	MAIL ADDRESS:	
		STREET 1:		12390 EL CAMINO REAL
		STREET 2:		SUITE 150
		CITY:			SAN DIEGO
		STATE:			CA
		ZIP:			92130

	FORMER COMPANY:	
		FORMER CONFORMED NAME:	ADVENTRX PHARMACEUTICALS INC
		DATE OF NAME CHANGE:	20030613

	FORMER COMPANY:	
		FORMER CONFORMED NAME:	BIOKEYS PHARMACEUTICALS INC
		DATE OF NAME CHANGE:	20010928
</SEC-HEADER>
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<TYPE>EFFECT
<SEQUENCE>1
<FILENAME>primary_doc.xml
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