<SEC-DOCUMENT>0001144204-12-050812.txt : 20120912
<SEC-HEADER>0001144204-12-050812.hdr.sgml : 20120912
<ACCEPTANCE-DATETIME>20120912123243
ACCESSION NUMBER:		0001144204-12-050812
CONFORMED SUBMISSION TYPE:	424B3
PUBLIC DOCUMENT COUNT:		1
FILED AS OF DATE:		20120912
DATE AS OF CHANGE:		20120912

FILER:

	COMPANY DATA:	
		COMPANY CONFORMED NAME:			Synthetic Biologics, Inc.
		CENTRAL INDEX KEY:			0000894158
		STANDARD INDUSTRIAL CLASSIFICATION:	PHARMACEUTICAL PREPARATIONS [2834]
		IRS NUMBER:				133808303
		STATE OF INCORPORATION:			NV
		FISCAL YEAR END:			1231

	FILING VALUES:
		FORM TYPE:		424B3
		SEC ACT:		1933 Act
		SEC FILE NUMBER:	333-180562
		FILM NUMBER:		121087291

	BUSINESS ADDRESS:	
		STREET 1:		3985 RESEARCH PARK DRIVE,
		STREET 2:		SUITE 200
		CITY:			ANN ARBOR
		STATE:			MI
		ZIP:			48108
		BUSINESS PHONE:		(734) 332-7800

	MAIL ADDRESS:	
		STREET 1:		3985 RESEARCH PARK DRIVE,
		STREET 2:		SUITE 200
		CITY:			ANN ARBOR
		STATE:			MI
		ZIP:			48108

	FORMER COMPANY:	
		FORMER CONFORMED NAME:	ADEONA PHARMACEUTICALS, INC.
		DATE OF NAME CHANGE:	20081027

	FORMER COMPANY:	
		FORMER CONFORMED NAME:	PIPEX PHARMACEUTICALS, INC.
		DATE OF NAME CHANGE:	20061214

	FORMER COMPANY:	
		FORMER CONFORMED NAME:	SHEFFIELD PHARMACEUTICALS INC
		DATE OF NAME CHANGE:	19970730
</SEC-HEADER>
<DOCUMENT>
<TYPE>424B3
<SEQUENCE>1
<FILENAME>v323544_424b3.htm
<DESCRIPTION>FORM 424B3
<TEXT>
<HTML>
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<P STYLE="margin: 0">&nbsp;</P>

<P STYLE="margin: 0"></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; text-align: center"><B>&nbsp;</B></P>

<P STYLE="font: 10pt Times New Roman, Times, Serif; margin: 0pt 0; text-align: right"><B>Filed Pursuant to Rule 424(b)(3)</B></P>

<P STYLE="font: 10pt Times New Roman, Times, Serif; margin: 0pt 0; text-align: right"><B>Registration Statement No.&nbsp;333-180562</B></P>

<P STYLE="font: 10pt Times New Roman, Times, Serif; margin: 0pt 0; text-align: right"><B>September 12, 2012</B></P>

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

<P STYLE="font: 10pt Times New Roman, Times, Serif; margin: 0pt 0; text-align: center">&nbsp;</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; text-align: center"><B>PROSPECTUS SUPPLEMENT NO. 4</B></P>

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

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

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

<P STYLE="font: 10pt Times New Roman, Times, Serif; margin: 0pt 0; text-align: center"><B>112,573 Shares of Common Stock</B></P>

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

<P STYLE="font: 10pt Times New Roman, Times, Serif; margin: 0pt 0; text-align: justify">This prospectus supplement amends and supplements
our prospectus, dated July 26, 2012 relating to the resale, from time to time, of up to 112,573 shares of common stock of Synthetic
Biologics, Inc. upon the exercise of warrants issued in July 2011 at an exercise price of $1.00 per share and warrants sold in
our July 2010 offering at an exercise price of $1.32 per share. <FONT STYLE="color: black">We will receive proceeds if the warrants
are exercised for cash; to the extent we receive such proceeds, they will be used for working capital purposes.</FONT></P>

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

<P STYLE="font: 10pt Times New Roman, Times, Serif; margin: 0pt 0; text-align: justify">Our common stock became eligible for trading
on the NYSE MKT October 16, 2008. &nbsp;Our common stock is eligible for quotation on the NYSE MKT under the symbol &ldquo;SYN&rdquo;.
The closing price of our stock on September 11, 2012 was $2.08.</P>

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

<P STYLE="font: 10pt Times New Roman, Times, Serif; margin: 0pt 0">This prospectus supplement is being filed to include the information
set forth in the Current Report on Form 10Q/A filed on September 11, 2012, which is set forth below. This prospectus supplement
should be read in conjunction with the prospectus dated July 26, 2012, supplement no. 1 dated August 9, 2012, prospectus supplement
no. 2 dated August 15, 2012, and prospectus supplement no. 3 dated August 15, 2012 which are to be delivered with this prospectus
supplement.</P>

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

<P STYLE="font: 10pt Times New Roman, Times, Serif; margin: 0pt 0"><B>Investing in our securities involves a high degree of risk.
See &ldquo;<U>Risk Factors</U>&rdquo; beginning on page 4 of the original prospectus for more information.</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; text-align: justify">Neither the Securities and Exchange Commission
nor any state securities commission has approved or disapproved of these securities or determined if this prospectus or the prospectus
to which it relates is truthful or complete. Any representation to the contrary is a criminal offense.</P>

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

<P STYLE="font: 10pt Times New Roman, Times, Serif; margin: 0pt 0; text-align: center">The date of this Prospectus Supplement No.
4 is September 12, 2012.</P>

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

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

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

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



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

<P STYLE="font: 10pt Times New Roman, Times, Serif; margin: 0pt 0; text-align: center"><B>UNITED STATES SECURITIES AND EXCHANGE
COMMISSION</B></P>

<P STYLE="font: 10pt Times New Roman, Times, Serif; margin: 0pt 0; text-align: center"><B>Washington, DC 20549</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; text-align: center"><B>FORM 10-Q/A</B></P>

<P STYLE="font: 10pt Times New Roman, Times, Serif; margin: 0pt 0; text-align: center"><B>Amendment No. 1</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">(Mark One)</P>

<TABLE CELLSPACING="0" CELLPADDING="0" STYLE="width: 100%; font: 10pt Times New Roman, Times, Serif; border-collapse: collapse">
<TR STYLE="vertical-align: top">
    <TD STYLE="width: 10%; padding-right: 0.8pt"><FONT STYLE="font-family: Wingdings">&#120;</FONT></TD>
    <TD STYLE="width: 90%; padding-right: 0.8pt; font-weight: bold"><B>QUARTERLY REPORT PURSUANT TO SECTION 13 OR 15(d) OF THE SECURITIES EXCHANGE ACT OF 1934</B></TD></TR>
<TR STYLE="vertical-align: top">
    <TD STYLE="padding-right: 0.8pt">&nbsp;</TD>
    <TD STYLE="padding-right: 0.8pt; font-weight: bold">&nbsp;</TD></TR>
<TR STYLE="vertical-align: top">
    <TD STYLE="padding-right: 0.8pt">&nbsp;</TD>
    <TD STYLE="padding-right: 0.8pt; font-weight: bold"><B>For the quarterly period ended June 30, 2012 &nbsp;</B></TD></TR>
</TABLE>
<P STYLE="font: 10pt Times New Roman, Times, Serif; margin: 0pt 0; text-align: center">&nbsp;</P>

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

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

<TABLE CELLSPACING="0" CELLPADDING="0" STYLE="width: 100%; font: 10pt Times New Roman, Times, Serif; border-collapse: collapse">
<TR STYLE="vertical-align: top">
    <TD STYLE="width: 10%; padding-right: 0.8pt"><FONT STYLE="font-family: Wingdings">&#168;</FONT></TD>
    <TD STYLE="width: 90%; padding-right: 0.8pt; font-weight: bold"><B>TRANSITION REPORT PURSUANT TO SECTION 13 OR 15(d) OF THE SECURITIES ACT OF 1934</B></TD></TR>
<TR STYLE="vertical-align: top">
    <TD STYLE="padding-right: 0.8pt">&nbsp;</TD>
    <TD STYLE="padding-right: 0.8pt; font-weight: bold">&nbsp;</TD></TR>
<TR STYLE="vertical-align: top">
    <TD STYLE="padding-right: 0.8pt">&nbsp;</TD>
    <TD STYLE="padding-right: 0.8pt; font-weight: bold"><B>For the transition period from &nbsp;____________ to&nbsp;____________ &nbsp;</B></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>Commission File Number: 1-12584</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; text-align: center"><B>SYNTHETIC BIOLOGICS, INC.</B></P>

<P STYLE="font: 10pt Times New Roman, Times, Serif; margin: 0pt 0; text-align: center"><I>(Name of small business issuer in its
charter)</I></P>

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

<TABLE CELLSPACING="0" CELLPADDING="0" STYLE="width: 100%; font: 10pt Times New Roman, Times, Serif; border-collapse: collapse">
<TR STYLE="vertical-align: bottom">
    <TD STYLE="width: 62%; padding-right: 0.8pt; font-weight: bold; text-align: center"><B>Nevada</B></TD>
    <TD STYLE="width: 1%; padding-right: 0.8pt">&nbsp;</TD>
    <TD STYLE="width: 37%; padding-right: 0.8pt; font-weight: bold; text-align: center"><B>13-3808303</B></TD></TR>
<TR STYLE="vertical-align: bottom">
    <TD STYLE="padding-right: 0.8pt; font-style: italic; text-align: center"><I>(State&nbsp;or&nbsp;other&nbsp;jurisdiction&nbsp;of&nbsp;incorporation&nbsp;or&nbsp;organization)</I></TD>
    <TD STYLE="padding-right: 0.8pt">&nbsp;</TD>
    <TD STYLE="padding-right: 0.8pt; font-style: italic; text-align: center"><I>(IRS&nbsp;Employer&nbsp;Identification&nbsp;Number)</I></TD></TR>
<TR STYLE="vertical-align: bottom">
    <TD STYLE="padding-right: 0.8pt">&nbsp;</TD>
    <TD STYLE="padding-right: 0.8pt">&nbsp;</TD>
    <TD STYLE="padding-right: 0.8pt">&nbsp;</TD></TR>
<TR STYLE="vertical-align: bottom">
    <TD STYLE="padding-right: 0.8pt; font-weight: bold; text-align: center"><B>617 Detroit Street, Suite 100</B></TD>
    <TD STYLE="padding-right: 0.8pt">&nbsp;</TD>
    <TD STYLE="padding-right: 0.8pt">&nbsp;</TD></TR>
<TR STYLE="vertical-align: bottom">
    <TD STYLE="padding-right: 0.8pt; font-weight: bold; text-align: center"><B>Ann&nbsp;Arbor,&nbsp;MI</B></TD>
    <TD STYLE="padding-right: 0.8pt">&nbsp;</TD>
    <TD STYLE="padding-right: 0.8pt; font-weight: bold; text-align: center"><B>48104</B></TD></TR>
<TR STYLE="vertical-align: bottom">
    <TD STYLE="padding-right: 0.8pt; font-style: italic; text-align: center"><I>(Address&nbsp;of&nbsp;principal&nbsp;executive&nbsp;offices)</I></TD>
    <TD STYLE="padding-right: 0.8pt">&nbsp;</TD>
    <TD STYLE="padding-right: 0.8pt; font-style: italic; text-align: center"><I>(Zip&nbsp;Code)</I></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>Registrant&rsquo;s telephone number,
including area code:</B></P>

<P STYLE="font: 10pt Times New Roman, Times, Serif; margin: 0pt 0; text-align: center"><B>(734) 332-7800</B></P>

<P STYLE="font: 10pt Times New Roman, Times, Serif; margin: 0pt 0; text-align: center"><B>Securities registered pursuant to Section
12(b) of the Act:</B></P>

<P STYLE="font: 10pt Times New Roman, Times, Serif; margin: 0pt 0; text-align: center"><B>Common Stock, $0.001 par value per share</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; text-align: center"><B>Securities registered pursuant to Section
12(g) of the Act:</B></P>

<P STYLE="font: 10pt Times New Roman, Times, Serif; margin: 0pt 0; text-align: center"><B>None.</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; text-align: center"><I>(Title of Class)</I></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; text-indent: 0.25in"><FONT STYLE="font-family: Times New Roman, Times, Serif">Indicate
by check mark whether the issuer: (1) has filed all reports required to be filed by Section 13 or 15(d) of the Securities Exchange
Act of 1934 during the preceding 12 months (or for such shorter period that the registrant was required to file such reports),
and (2) has been subject to such filing requirements for the past 90 days.&nbsp; Yes&nbsp;&nbsp; </FONT><FONT STYLE="font-family: Wingdings">x</FONT><FONT STYLE="font-family: Times New Roman, Times, Serif">
&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;No&nbsp; </FONT><FONT STYLE="font-family: Wingdings">&uml;</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; text-align: justify; text-indent: 0.25in"><FONT STYLE="font-family: Times New Roman, Times, Serif">Indicate
by check mark whether the registrant has submitted electronically and posted on its corporate Web site, if any, every Interactive
Data File required to be submitted and posted pursuant to Rule 405 of Regulation S-T during the preceding 12 months (or for such
shorter period that the registrant was required to submit and post such files).&nbsp;&nbsp;Yes&nbsp;&nbsp; </FONT><FONT STYLE="font-family: Wingdings">x</FONT><FONT STYLE="font-family: Times New Roman, Times, Serif">
&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;No&nbsp; </FONT><FONT STYLE="font-family: Wingdings">&uml;</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; text-align: justify; text-indent: 0.25in">Indicate by check
mark whether the registrant is a large accelerated filer, an accelerated file, a non-accelerated file, or a smaller reporting company.&nbsp;&nbsp;See
the definitions of &ldquo;large accelerated filer,&nbsp;&ldquo;accelerated filer&rdquo; and &ldquo;smaller reporting company&rdquo;
in Rule 12b-2 of the Exchange Act.&nbsp;&nbsp;(Check one):</P>

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

<TABLE CELLSPACING="0" CELLPADDING="0" STYLE="width: 100%; font: 10pt Times New Roman, Times, Serif; border-collapse: collapse">
<TR STYLE="vertical-align: bottom">
    <TD STYLE="width: 53%; padding-right: 0.8pt"><FONT STYLE="font-family: Times New Roman, Times, Serif">Large&nbsp;accelerated&nbsp;filer&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; </FONT><FONT STYLE="font-family: Wingdings">&uml;</FONT></TD>
    <TD STYLE="width: 47%; padding-right: 0.8pt"><FONT STYLE="font-family: Times New Roman, Times, Serif">Accelerated&nbsp;filer&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; </FONT><FONT STYLE="font-family: Wingdings">&uml;</FONT></TD></TR>
<TR STYLE="vertical-align: bottom">
    <TD STYLE="padding-right: 0.8pt"><FONT STYLE="font-family: Times New Roman, Times, Serif">Non-Accelerated&nbsp;filer&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; </FONT><FONT STYLE="font-family: Wingdings">&uml;</FONT></TD>
    <TD STYLE="padding-right: 0.8pt"><FONT STYLE="font-family: Times New Roman, Times, Serif">Smaller&nbsp;reporting&nbsp;company&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; </FONT><FONT STYLE="font-family: Wingdings">x</FONT></TD></TR>
<TR STYLE="vertical-align: bottom">
    <TD STYLE="padding-right: 0.8pt">(Do&nbsp;not&nbsp;check&nbsp;if&nbsp;a&nbsp;smaller&nbsp;reporting&nbsp;company)</TD>
    <TD STYLE="padding-right: 0.8pt">&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"><FONT STYLE="font-family: Times New Roman, Times, Serif">Indicate
by check mark whether the registrant is a shell company (as defined in Rule 12b-2 of the Exchange Act).&nbsp;&nbsp;&nbsp;Yes&nbsp;
</FONT><FONT STYLE="font-family: Wingdings">&uml;</FONT><FONT STYLE="font-family: Times New Roman, Times, Serif"> &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;No&nbsp;
</FONT><FONT STYLE="font-family: Wingdings">x</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">As of August 9, 2012, the registrant had 33,395,538 shares of
common stock outstanding.</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"></P>

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

<P STYLE="font: 10pt Times New Roman, Times, Serif; margin: 0pt 0; text-align: justify">Explanatory Note</P>

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

<P STYLE="font: 10pt Times New Roman, Times, Serif; margin: 0pt 0; text-align: justify">Synthetic Biologics, Inc. (the &ldquo;Company&rdquo;)
is filing this Amendment No. 1 on Form 10-Q/A (the &ldquo;Amendment&rdquo;) to the Company&rsquo;s Quarterly Report on Form 10-Q
for the period ended June 30, 2012 (the &ldquo;Form 10-Q&rdquo;), filed with the Securities and Exchange Commission on August 14,
2012 (the &ldquo;Original Filing Date&rdquo;), for the sole purpose of furnishing Exhibit 101 to the Form 10-Q in accordance with
Rule 405 of Regulation S-T. Exhibit 101 consists of the following materials from the Form 10-Q, formatted in XBRL (eXtensible Business
Reporting Language):</P>

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

<TABLE CELLSPACING="0" CELLPADDING="0" STYLE="width: 100%; font: 10pt Times New Roman, Times, Serif; border-collapse: collapse">
<TR STYLE="vertical-align: top">
    <TD STYLE="width: 11%; padding-right: 0.8pt">101.INS</TD>
    <TD STYLE="width: 89%; padding-right: 0.8pt">XBRL Instance Document</TD></TR>
<TR STYLE="vertical-align: top">
    <TD STYLE="padding-right: 0.8pt">101.SCH</TD>
    <TD STYLE="padding-right: 0.8pt">XBRL Taxonomy Schema</TD></TR>
<TR STYLE="vertical-align: top">
    <TD STYLE="padding-right: 0.8pt">101.CAL</TD>
    <TD STYLE="padding-right: 0.8pt">XBRL Taxonomy Calculation Linkbase</TD></TR>
<TR STYLE="vertical-align: top">
    <TD STYLE="padding-right: 0.8pt">101.DEF</TD>
    <TD STYLE="padding-right: 0.8pt">XBRL Taxonomy Definition Linkbase</TD></TR>
<TR STYLE="vertical-align: top">
    <TD STYLE="padding-right: 0.8pt">101.LAB</TD>
    <TD STYLE="padding-right: 0.8pt">XBRL Taxonomy Label Linkbase</TD></TR>
<TR STYLE="vertical-align: top">
    <TD STYLE="padding-right: 0.8pt">101.PRE</TD>
    <TD STYLE="padding-right: 0.8pt">XBRL Taxonomy Presentation Linkbase</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: justify">No other changes have been made to the
Form 10-Q. This Amendment speaks as of the Original Filing Date, does not reflect events that may have occurred subsequent to the
Original Filing Date, and does not modify or update in any way disclosures made in the Form 10-Q.</P>

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

<P STYLE="font: 10pt Times New Roman, Times, Serif; margin: 0pt 0; text-align: justify">Pursuant to Rule 406T of Regulation S-T,
the interactive data files attached as Exhibit 101 hereto are deemed not filed or part of a registration statement or prospectus
for purposes of Sections 11 or 12 of the Securities Act of 1933, as amended, are deemed not filed for purposes of Section 18 of
the Securities Exchange Act of 1934, as amended, and otherwise are not subject to liability under those sections. <B>&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;</B></P>

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

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

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    <TD STYLE="width: 11%; padding-right: 0.8pt; font-weight: bold"><B>Item 6.&nbsp;</B></TD>
    <TD STYLE="width: 89%; padding-right: 0.8pt; font-weight: bold"><B>Exhibits</B></TD></TR>
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    <TD STYLE="width: 9%; border-bottom: black 1.5pt solid; padding-right: 0.8pt; font-weight: bold"><B>Exhibit Number</B></TD>
    <TD STYLE="width: 2%; padding-right: 0.8pt">&nbsp;</TD>
    <TD STYLE="width: 89%; border-bottom: black 1.5pt solid; padding-right: 0.8pt; font-weight: bold"><B>Exhibit Title</B></TD></TR>
<TR STYLE="vertical-align: top; background-color: rgb(204,255,204)">
    <TD STYLE="padding-right: 0.8pt">31.1*</TD>
    <TD STYLE="padding-right: 0.8pt">&nbsp;</TD>
    <TD STYLE="padding-right: 0.8pt">Certification of Chief Executive Officer Pursuant to Section 302 of the Sarbanes-Oxley Act of 2002.</TD></TR>
<TR STYLE="vertical-align: top; background-color: White">
    <TD STYLE="padding-right: 0.8pt">31.2*</TD>
    <TD STYLE="padding-right: 0.8pt">&nbsp;</TD>
    <TD STYLE="padding-right: 0.8pt">Certification of Chief Financial Officer Pursuant to Section 302 of the Sarbanes-Oxley Act of 2002</TD></TR>
<TR STYLE="vertical-align: top; background-color: rgb(204,255,204)">
    <TD STYLE="padding-right: 0.8pt">32.1*</TD>
    <TD STYLE="padding-right: 0.8pt">&nbsp;</TD>
    <TD STYLE="padding-right: 0.8pt">Certification of Chief Executive Officer pursuant to 18 U.S.C Section 1350, as adopted pursuant to Section 906 of the Sarbanes-Oxley Act of 2002</TD></TR>
<TR STYLE="vertical-align: top; background-color: White">
    <TD STYLE="padding-right: 0.8pt">32.2*</TD>
    <TD STYLE="padding-right: 0.8pt">&nbsp;</TD>
    <TD STYLE="padding-right: 0.8pt">Certification of Chief Financial Officer pursuant to 18 U.S.C Section 1350, as adopted pursuant to Section 906 of the Sarbanes-Oxley Act of 2002</TD></TR>
<TR STYLE="vertical-align: top; background-color: rgb(204,255,204)">
    <TD STYLE="padding-right: 0.8pt">101.INS **</TD>
    <TD STYLE="padding-right: 0.8pt">&nbsp;</TD>
    <TD STYLE="padding-right: 0.8pt">XBRL Instance Document</TD></TR>
<TR STYLE="vertical-align: top; background-color: White">
    <TD STYLE="padding-right: 0.8pt">101.SCH **</TD>
    <TD STYLE="padding-right: 0.8pt">&nbsp;</TD>
    <TD STYLE="padding-right: 0.8pt">XBRL Taxonomy Schema</TD></TR>
<TR STYLE="vertical-align: top; background-color: rgb(204,255,204)">
    <TD STYLE="padding-right: 0.8pt">101.CAL **</TD>
    <TD STYLE="padding-right: 0.8pt">&nbsp;</TD>
    <TD STYLE="padding-right: 0.8pt">XBRL Taxonomy Calculation Linkbase</TD></TR>
<TR STYLE="vertical-align: top; background-color: White">
    <TD STYLE="padding-right: 0.8pt">101.DEF **</TD>
    <TD STYLE="padding-right: 0.8pt">&nbsp;</TD>
    <TD STYLE="padding-right: 0.8pt">XBRL Taxonomy Definition Linkbase</TD></TR>
<TR STYLE="vertical-align: top; background-color: rgb(204,255,204)">
    <TD STYLE="padding-right: 0.8pt">101.LAB **</TD>
    <TD STYLE="padding-right: 0.8pt">&nbsp;</TD>
    <TD STYLE="padding-right: 0.8pt">XBRL Taxonomy Label Linkbase</TD></TR>
<TR STYLE="vertical-align: top; background-color: White">
    <TD STYLE="padding-right: 0.8pt">101.PRE **</TD>
    <TD STYLE="padding-right: 0.8pt">&nbsp;</TD>
    <TD STYLE="padding-right: 0.8pt">XBRL Taxonomy Presentation Linkbase</TD></TR>
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<P STYLE="font: 10pt Times New Roman, Times, Serif; margin: 0pt 0; text-align: justify">&nbsp;</P>

<P STYLE="font: 10pt Times New Roman, Times, Serif; margin: 0pt 0; text-align: justify">* Previously filed as an exhibit to the
Company&rsquo;s Form 10-Q for the period ended June 30, 2012 filed with the Securities and Exchange Commission on August 14, 2012.</P>

<P STYLE="font: 10pt Times New Roman, Times, Serif; margin: 0pt 0; text-align: justify">** Furnished herewith. XBRL (eXtensible
Business Reporting Language) information is furnished and not filed or a part of a registration statement or prospectus for purposes
of Sections 11 or 12 of the Securities Act of 1933, as amended, is deemed not filed for purposes of Section 18 of the Securities
Exchange Act of 1934, as amended, and otherwise is not subject to liability under these sections.</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">&nbsp;</P>

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<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">&nbsp;</P>

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

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    <TD STYLE="padding-right: 0.8pt">&nbsp;</TD>
    <TD COLSPAN="2" STYLE="padding-right: 1.8pt">SYNTHETIC BIOLOGICS, INC.</TD></TR>
<TR STYLE="vertical-align: top">
    <TD STYLE="width: 56%; padding-right: 0.8pt">&nbsp;</TD>
    <TD STYLE="width: 5%; padding-right: 0.8pt">&nbsp;</TD>
    <TD STYLE="width: 39%; padding-right: 0.8pt">&nbsp;</TD></TR>
<TR STYLE="vertical-align: top">
    <TD STYLE="padding-right: 0.8pt">&nbsp;</TD>
    <TD STYLE="padding-right: 0.8pt">By:</TD>
    <TD STYLE="border-bottom: black 1pt solid; padding-right: 0.8pt">/s/&nbsp;Jeffrey Riley</TD></TR>
<TR STYLE="vertical-align: top">
    <TD STYLE="padding-right: 0.8pt">&nbsp;</TD>
    <TD STYLE="padding-right: 0.8pt">&nbsp;</TD>
    <TD STYLE="padding-right: 0.8pt; text-align: justify">Jeffrey Riley</TD></TR>
<TR STYLE="vertical-align: top">
    <TD STYLE="padding-right: 0.8pt">&nbsp;</TD>
    <TD STYLE="padding-right: 0.8pt">&nbsp;</TD>
    <TD STYLE="padding-right: 0.8pt">President and Chief Executive Officer</TD></TR>
<TR STYLE="vertical-align: top">
    <TD STYLE="padding-right: 0.8pt">&nbsp;</TD>
    <TD STYLE="padding-right: 0.8pt">&nbsp;</TD>
    <TD STYLE="padding-right: 0.8pt">(Principal Executive Officer)</TD></TR>
<TR STYLE="vertical-align: top">
    <TD STYLE="padding-right: 0.8pt">&nbsp;</TD>
    <TD STYLE="padding-right: 0.8pt">&nbsp;</TD>
    <TD STYLE="padding-right: 0.8pt">Date: September 11, 2012</TD></TR>
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    <TD STYLE="width: 56%; padding-right: 0.8pt">&nbsp;</TD>
    <TD STYLE="width: 5%; padding-right: 0.8pt">By:</TD>
    <TD STYLE="width: 39%; border-bottom: black 1pt solid; padding-right: 0.8pt">/s/ C. Evan Ballantyne &nbsp;</TD></TR>
<TR STYLE="vertical-align: top">
    <TD COLSPAN="2" STYLE="padding-right: 1.8pt">&nbsp;</TD>
    <TD STYLE="padding-right: 0.8pt">C. Evan Ballantyne</TD></TR>
<TR STYLE="vertical-align: top">
    <TD COLSPAN="2" STYLE="padding-right: 1.8pt">&nbsp;</TD>
    <TD STYLE="padding-right: 0.8pt">Chief Financial Officer</TD></TR>
<TR STYLE="vertical-align: top">
    <TD COLSPAN="2" STYLE="padding-right: 1.8pt">&nbsp;</TD>
    <TD STYLE="padding-right: 0.8pt">(Principal Financial Officer)</TD></TR>
<TR STYLE="vertical-align: top">
    <TD COLSPAN="2" STYLE="padding-right: 1.8pt">&nbsp;</TD>
    <TD STYLE="padding-right: 0.8pt">Date: September 11, 2012</TD></TR>
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