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		UNITED STATES<BR>
	SECURITIES AND EXCHANGE COMMISSION
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	WASHINGTON, D.C. 20549
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	FORM 8-K
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	CURRENT REPORT
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	Pursuant to Section&nbsp;13 or 15(d) of the Securities Exchange Act of 1934
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	Date of Report (Date of Earliest Event Reported):
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	January 7, 2015
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	Mast Therapeutics, Inc.
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<BR>__________________________________________<BR>
	(Exact name of registrant as specified in its charter)
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	Delaware
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	001-32157
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	84-1318182
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_____________________<BR>
	(State or other jurisdiction
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_____________<BR>
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	of incorporation)
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	File Number)
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	Identification No.)
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	12390 El Camino Real, Suite 150, San Diego, California
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	92130
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_________________________________<BR>
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	858-552-0866
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	Not Applicable
<BR>______________________________________________<BR>
	Former name or former address, if changed since last report
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	&nbsp;
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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:</FONT>
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[&nbsp;&nbsp;]&nbsp;&nbsp;Written communications pursuant to Rule 425 under the Securities Act (17 CFR 230.425)<br>
[&nbsp;&nbsp;]&nbsp;&nbsp;Soliciting material pursuant to Rule 14a-12 under the Exchange Act (17 CFR 240.14a-12)<br>
[&nbsp;&nbsp;]&nbsp;&nbsp;Pre-commencement communications pursuant to Rule 14d-2(b) under the Exchange Act (17 CFR 240.14d-2(b))<br>
[&nbsp;&nbsp;]&nbsp;&nbsp;Pre-commencement communications pursuant to Rule 13e-4(c) under the Exchange Act (17 CFR 240.13e-4(c))<br>
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	Item 8.01 Other Events.
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Mast Therapeutics, Inc. (the "Company") currently anticipates that its 2015 operating expenses will be in the mid $30 millions.
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<BR><BR><BR><BR><P ALIGN="LEFT" STYLE="FONT-SIZE: 10PT">By filing this report the Company makes no admission as to the materiality of any information in this report. The information contained herein is summary information that is intended to be considered in the context of the Company&#x2019;s filings with the U.S. Securities and Exchange Commission (the &#x201C;SEC&#x201D;), including its Annual Report on Form 10-K filed on March 26, 2014, Quarterly Report on Form 10-Q filed on October 31, 2014, and other public announcements that the Company makes, by press release or otherwise, from time to time. The Company undertakes no duty or obligation to publicly update or revise the information contained in this report, although it may do so from time to time as it believes is appropriate. Any such updating may be made through the filing of other reports or documents with the SEC, through press releases, or through other public disclosure. <br><br>Forward-Looking Statements<br>Mast Therapeutics cautions you that statements included in this report that are not a description of historical facts are forward-looking statements that are based on the Company&#x2019;s current expectations and assumptions. Such forward-looking statements include, but are not limited to, statements regarding the Company&#x2019;s expected operating expenses for 2015. Among the factors that could cause or contribute to material differences between the Company&#x2019;s actual results and the expectations indicated by the forward-looking statements are risks and uncertainties that include, but are not limited to: delays in the commencement or completion of clinical studies, including the EPIC study, the phase 2 study of vepoloxamer in acute limb ischemia, the planned phase 2 study of vepoloxamer in heart failure and the phase 2a studies of AIR001, including as a result of difficulties in obtaining regulatory agency agreement on clinical development plans or clinical study design, opening trial sites, enrolling study subjects, manufacturing sufficient quantities of clinical trial material, completing manufacturing process development activities, being subject to a &#x201C;clinical hold,&#x201D; and/or suspension or termination of a clinical study, including due to patient safety concerns or lack of funding; the potential for institutional review boards or the FDA or other regulatory agencies to require additional nonclinical or clinical studies prior to initiation of planned clinical study of a product candidate; the risk that, even if clinical studies are successful, the FDA or another regulatory agency may determine they are not sufficient to support a new drug application; the potential that even if clinical studies of a product candidate in one indication are successful, clinical studies in another indication may not be successful; the Company&#x2019;s reliance on contract research organizations (CROs), contract manufacturing organizations (CMOs), and other third parties to assist in the conduct of important aspects of development of its product candidates, including clinical studies, manufacturing, and regulatory activities for its product candidates and that such third parties may fail to perform as expected, which may impact anticipated operating costs; the risk that the Company is not able to adequately protect its intellectual property rights and prevent competitors from duplicating or developing equivalent versions of its product candidates or that it expends more capital than anticipated to protect or defend such its rights; and other risks and uncertainties more fully described in the Company&#x2019;s periodic filings with the SEC and press releases.<br>You are cautioned not to place undue reliance on forward-looking statements, which speak only as of the date they are made. Mast Therapeutics does not intend to revise or update any forward-looking statement set forth in this report to reflect events or circumstances arising after the date hereof, except as may be required by law. This caution is made under the safe harbor provisions of Section 21E of the Securities Exchange Act of 1934, as amended, and Section 27A of the Securities Act of 1933, as amended.</P><!-- PageBreak START -->
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	SIGNATURES
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	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.
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	Mast Therapeutics, Inc.
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	January 7, 2015
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	By:
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	/s/ Patrick L. Keran
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	Name: Patrick L. Keran
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	Title: President and Chief Operating Officer
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Mast Therapeutics, Inc. (Form: 8-K)
UNITED STATES
SECURITIES AND EXCHANGE COMMISSION
WASHINGTON, D.C. 20549
FORM 8-K
CURRENT REPORT
Pursuant to Section 13 or 15(d) of the Securities Exchange Act of 1934
Date of Report (Date of Earliest Event Reported):
January 7, 2015
Mast Therapeutics, Inc.
__________________________________________
(Exact name of registrant as specified in its charter)
Delaware
001-32157
84-1318182
_____________________
(State or other jurisdiction
_____________
(Commission
______________
(I.R.S. Employer
of incorporation)
File Number)
Identification No.)
12390 El Camino Real, Suite 150, San Diego, California
92130
_________________________________
(Address of principal executive offices)
___________
(Zip Code)
Registrant's telephone number, including area code:
858-552-0866
Not Applicable
______________________________________________
Former name or former address, if changed since last report
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:
[  ]  Written communications pursuant to Rule 425 under the Securities Act (17 CFR 230.425)
[  ]  Soliciting material pursuant to Rule 14a-12 under the Exchange Act (17 CFR 240.14a-12)
[  ]  Pre-commencement communications pursuant to Rule 14d-2(b) under the Exchange Act (17 CFR 240.14d-2(b))
[  ]  Pre-commencement communications pursuant to Rule 13e-4(c) under the Exchange Act (17 CFR 240.13e-4(c))
Top of the Form
Item 8.01 Other Events.
Mast Therapeutics, Inc. (the "Company") currently anticipates that its 2015 operating expenses will be in the mid $30 millions.
By filing this report the Company makes no admission as to the materiality of any information in this report. The information contained herein is summary information that is intended to be considered in the context of the Company's filings with the U.S. Securities and Exchange Commission (the "SEC"), including its Annual Report on Form 10-K filed on March 26, 2014, Quarterly Report on Form 10-Q filed on October 31, 2014, and other public announcements that the Company makes, by press release or otherwise, from time to time. The Company undertakes no duty or obligation to publicly update or revise the information contained in this report, although it may do so from time to time as it believes is appropriate. Any such updating may be made through the filing of other reports or documents with the SEC, through press releases, or through other public disclosure.
Forward-Looking Statements
Mast Therapeutics cautions you that statements included in this report that are not a description of historical facts are forward-looking statements that are based on the Company's current expectations and assumptions. Such forward-looking statements include, but are not limited to, statements regarding the Company's expected operating expenses for 2015. Among the factors that could cause or contribute to material differences between the Company's actual results and the expectations indicated by the forward-looking statements are risks and uncertainties that include, but are not limited to: delays in the commencement or completion of clinical studies, including the EPIC study, the phase 2 study of vepoloxamer in acute limb ischemia, the planned phase 2 study of vepoloxamer in heart failure and the phase 2a studies of AIR001, including as a result of difficulties in obtaining regulatory agency agreement on clinical development plans or clinical study design, opening trial sites, enrolling study subjects, manufacturing sufficient quantities of clinical trial material, completing manufacturing process development activities, being subject to a "clinical hold," and/or suspension or termination of a clinical study, including due to patient safety concerns or lack of funding; the potential for institutional review boards or the FDA or other regulatory agencies to require additional nonclinical or clinical studies prior to initiation of planned clinical study of a product candidate; the risk that, even if clinical studies are successful, the FDA or another regulatory agency may determine they are not sufficient to support a new drug application; the potential that even if clinical studies of a product candidate in one indication are successful, clinical studies in another indication may not be successful; the Company's reliance on contract research organizations (CROs), contract manufacturing organizations (CMOs), and other third parties to assist in the conduct of important aspects of development of its product candidates, including clinical studies, manufacturing, and regulatory activities for its product candidates and that such third parties may fail to perform as expected, which may impact anticipated operating costs; the risk that the Company is not able to adequately protect its intellectual property rights and prevent competitors from duplicating or developing equivalent versions of its product candidates or that it expends more capital than anticipated to protect or defend such its rights; and other risks and uncertainties more fully described in the Company's periodic filings with the SEC and press releases.
You are cautioned not to place undue reliance on forward-looking statements, which speak only as of the date they are made. Mast Therapeutics does not intend to revise or update any forward-looking statement set forth in this report to reflect events or circumstances arising after the date hereof, except as may be required by law. This caution is made under the safe harbor provisions of Section 21E of the Securities Exchange Act of 1934, as amended, and Section 27A of the Securities Act of 1933, as amended.
Top of the Form
SIGNATURES
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.
Mast Therapeutics, Inc.
January 7, 2015
By:
/s/ Patrick L. Keran
Name: Patrick L. Keran
Title: President and Chief Operating Officer