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 <P STYLE="line-height:1.0pt;margin-top:0pt;margin-bottom:0pt;border-bottom:1px solid #000000">&nbsp;</P>
<P STYLE="line-height:3.0pt;margin-top:0pt;margin-bottom:2pt;border-bottom:1px solid #000000">&nbsp;</P> <P STYLE="margin-top:4pt; margin-bottom:0pt; font-size:18pt; font-family:Times New Roman" ALIGN="center"><B>UNITED STATES </B></P>
<P STYLE="margin-top:0pt; margin-bottom:0pt; font-size:18pt; font-family:Times New Roman" ALIGN="center"><B>SECURITIES AND EXCHANGE COMMISSION </B></P>
<P STYLE="margin-top:0pt; margin-bottom:0pt; font-size:12pt; font-family:Times New Roman" ALIGN="center"><B>WASHINGTON, D.C. 20549 </B></P> <P STYLE="font-size:12pt;margin-top:0pt;margin-bottom:0pt">&nbsp;</P><center>
<P STYLE="line-height:6.0pt;margin-top:0pt;margin-bottom:2pt;border-bottom:1.00pt solid #000000;width:21%">&nbsp;</P></center> <P STYLE="margin-top:12pt; margin-bottom:0pt; font-size:18pt; font-family:Times New Roman" ALIGN="center"><B>FORM 8-K
</B></P> <P STYLE="font-size:12pt;margin-top:0pt;margin-bottom:0pt">&nbsp;</P><center> <P STYLE="line-height:6.0pt;margin-top:0pt;margin-bottom:2pt;border-bottom:1.00pt solid #000000;width:21%">&nbsp;</P></center>
<P STYLE="margin-top:12pt; margin-bottom:0pt; font-size:12pt; font-family:Times New Roman" ALIGN="center"><B>CURRENT REPORT </B></P> <P STYLE="margin-top:0pt; margin-bottom:0pt; font-size:12pt; font-family:Times New Roman" ALIGN="center"><B>Pursuant
to Section&nbsp;13 or 15(d) </B></P> <P STYLE="margin-top:0pt; margin-bottom:0pt; font-size:12pt; font-family:Times New Roman" ALIGN="center"><B>of the&nbsp;Securities Exchange Act of 1934 </B></P>
<P STYLE="margin-top:12pt; margin-bottom:0pt; font-size:12pt; font-family:Times New Roman" ALIGN="center"><B>Date of Report (Date of earliest event reported): October&nbsp;29, 2013 (October 29, 2013) </B></P>
<P STYLE="font-size:12pt;margin-top:0pt;margin-bottom:0pt">&nbsp;</P><center> <P STYLE="line-height:6.0pt;margin-top:0pt;margin-bottom:2pt;border-bottom:1.00pt solid #000000;width:21%">&nbsp;</P></center>
<P STYLE="margin-top:12pt; margin-bottom:0pt; font-size:24pt; font-family:Times New Roman" ALIGN="center"><B>ARCA biopharma, Inc. </B></P>
<P STYLE="margin-top:0pt; margin-bottom:0pt; font-size:10pt; font-family:Times New Roman" ALIGN="center"><B>(Exact Name of Registrant as Specified in Charter) </B></P> <P STYLE="font-size:12pt;margin-top:0pt;margin-bottom:0pt">&nbsp;</P><center>
<P STYLE="line-height:6.0pt;margin-top:0pt;margin-bottom:2pt;border-bottom:1.00pt solid #000000;width:21%">&nbsp;</P></center> <P STYLE="font-size:12pt;margin-top:0pt;margin-bottom:0pt">&nbsp;</P>
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<TD VALIGN="top" ALIGN="center"><B>Delaware</B></TD>
<TD VALIGN="bottom">&nbsp;</TD>
<TD VALIGN="top" ALIGN="center"><B>000-22873</B></TD>
<TD VALIGN="bottom">&nbsp;</TD>
<TD VALIGN="top" ALIGN="center"><B>36-3855489</B></TD></TR>
<TR STYLE="font-family:Times New Roman; font-size:8pt">
<TD VALIGN="top" ALIGN="center"> <P STYLE="margin-top:0pt; margin-bottom:0pt; font-size:8pt; font-family:Times New Roman" ALIGN="center"><B>(State or Other Jurisdiction</B></P>
<P STYLE="margin-top:0pt; margin-bottom:1pt; font-size:8pt; font-family:Times New Roman" ALIGN="center"><B>of Incorporation)</B></P></TD>
<TD VALIGN="bottom">&nbsp;</TD>
<TD VALIGN="top" ALIGN="center"> <P STYLE="margin-top:0pt; margin-bottom:0pt; font-size:8pt; font-family:Times New Roman" ALIGN="center"><B>(Commission</B></P>
<P STYLE="margin-top:0pt; margin-bottom:1pt; font-size:8pt; font-family:Times New Roman" ALIGN="center"><B>File Number)</B></P></TD>
<TD VALIGN="bottom">&nbsp;</TD>
<TD VALIGN="top" ALIGN="center"> <P STYLE="margin-top:0pt; margin-bottom:0pt; font-size:8pt; font-family:Times New Roman" ALIGN="center"><B>(I.R.S. Employer</B></P>
<P STYLE="margin-top:0pt; margin-bottom:1pt; font-size:8pt; font-family:Times New Roman" ALIGN="center"><B>Identification No.)</B></P></TD></TR>
</TABLE> <P STYLE="margin-top:12pt; margin-bottom:0pt; font-size:10pt; font-family:Times New Roman" ALIGN="center"><B>11080 CirclePoint Road, Suite 140, Westminster, CO 80020 </B></P>
<P STYLE="margin-top:0pt; margin-bottom:0pt; font-size:8pt; font-family:Times New Roman" ALIGN="center"><B>(Address of Principal Executive Offices) (Zip Code) </B></P>
<P STYLE="margin-top:12pt; margin-bottom:0pt; font-size:10pt; font-family:Times New Roman" ALIGN="center"><B>(720) 940-2200 </B></P>
<P STYLE="margin-top:0pt; margin-bottom:0pt; font-size:8pt; font-family:Times New Roman" ALIGN="center"><B>(Registrant&#146;s telephone number, including area code) </B></P>
<P STYLE="margin-top:12pt; margin-bottom:0pt; font-size:10pt; font-family:Times New Roman" ALIGN="center"><B>Not Applicable </B></P> <P STYLE="margin-top:0pt; margin-bottom:0pt; font-size:8pt; font-family:Times New Roman" ALIGN="center"><B>(Former
Name or Former Address, if Changed Since Last Report) </B></P> <P STYLE="font-size:12pt;margin-top:0pt;margin-bottom:0pt">&nbsp;</P><center>
<P STYLE="line-height:6.0pt;margin-top:0pt;margin-bottom:2pt;border-bottom:1.00pt solid #000000;width:21%">&nbsp;</P></center> <P STYLE="margin-top:12pt; margin-bottom:0pt; font-size:10pt; font-family:Times New Roman">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 (see General Instruction A.2. below): </P>
<P STYLE="font-size:6pt;margin-top:0pt;margin-bottom:0pt">&nbsp;</P>
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<TR>
<TD WIDTH="4%" VALIGN="top" ALIGN="left"><FONT STYLE="FONT-FAMILY:WINGDINGS">&#168;</FONT></TD>
<TD ALIGN="left" VALIGN="top">Written communications pursuant to Rule 425 under the Securities Act (17 CFR 230.425) </TD></TR></TABLE> <P STYLE="font-size:6pt;margin-top:0pt;margin-bottom:0pt">&nbsp;</P>
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<TD WIDTH="4%" VALIGN="top" ALIGN="left"><FONT STYLE="FONT-FAMILY:WINGDINGS">&#168;</FONT></TD>
<TD ALIGN="left" VALIGN="top">Soliciting material pursuant to Rule 14a-12 under the Exchange Act (17 CFR 240.14a-12) </TD></TR></TABLE> <P STYLE="font-size:6pt;margin-top:0pt;margin-bottom:0pt">&nbsp;</P>
<TABLE STYLE="BORDER-COLLAPSE:COLLAPSE; font-family:Times New Roman; font-size:10pt" BORDER="0" CELLPADDING="0" CELLSPACING="0" WIDTH="100%">
<TR>
<TD WIDTH="4%" VALIGN="top" ALIGN="left"><FONT STYLE="FONT-FAMILY:WINGDINGS">&#168;</FONT></TD>
<TD ALIGN="left" VALIGN="top">Pre-commencement communications pursuant to Rule 14d-2(b) under the Exchange Act (17 CFR 240.14d-2(b)) </TD></TR></TABLE> <P STYLE="font-size:6pt;margin-top:0pt;margin-bottom:0pt">&nbsp;</P>
<TABLE STYLE="BORDER-COLLAPSE:COLLAPSE; font-family:Times New Roman; font-size:10pt" BORDER="0" CELLPADDING="0" CELLSPACING="0" WIDTH="100%">
<TR>
<TD WIDTH="4%" VALIGN="top" ALIGN="left"><FONT STYLE="FONT-FAMILY:WINGDINGS">&#168;</FONT></TD>
<TD ALIGN="left" VALIGN="top">Pre-commencement communications pursuant to Rule 13e-4(c) under the Exchange Act (17 CFR 240.13e-4(c)) </TD></TR></TABLE> <P STYLE="font-size:10pt;margin-top:0pt;margin-bottom:0pt">&nbsp;</P>
<P STYLE="line-height:1.0pt;margin-top:0pt;margin-bottom:0pt;border-bottom:1px solid #000000">&nbsp;</P> <P STYLE="line-height:3.0pt;margin-top:0pt;margin-bottom:2pt;border-bottom:1px solid #000000">&nbsp;</P>

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 <P STYLE="margin-top:0pt; margin-bottom:0pt; font-size:10pt; font-family:Times New Roman"><B>Section&nbsp;8 &#151; Other Events </B></P>
<P STYLE="margin-top:6pt; margin-bottom:0pt; font-size:10pt; font-family:Times New Roman"><B>Item&nbsp;8.01. Other Events. </B></P> <P STYLE="margin-top:6pt; margin-bottom:0pt; text-indent:8%; font-size:10pt; font-family:Times New Roman">On
October&nbsp;29, 2013, ARCA biopharma, Inc. announced that it submitted an Investigational New Drug (IND) application to the U.S. Food and Drug Administration for the GENETIC-AF clinical trial of Gencaro (bucindolol hydrochloride), a
pharmacologically unique beta-blocker and mild vasodilator being developed for atrial fibrillation, and has established the Data Safety Monitoring Board for GENETIC-AF. The press release is furnished as Exhibit 99.1 hereto, the contents of which are
incorporated herein by reference. </P> <P STYLE="margin-top:18pt; margin-bottom:0pt; font-size:10pt; font-family:Times New Roman"><B>Section&nbsp;9 &#151; Financial Statements and Exhibits </B></P>
<P STYLE="margin-top:6pt; margin-bottom:0pt; font-size:10pt; font-family:Times New Roman"><B>Item&nbsp;9.01. Financial Statements and Exhibits. </B></P> <P STYLE="margin-top:6pt; margin-bottom:0pt; font-size:10pt; font-family:Times New Roman">(d)
Exhibits. </P> <P STYLE="font-size:12pt;margin-top:0pt;margin-bottom:0pt">&nbsp;</P>
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<TD VALIGN="bottom" NOWRAP ALIGN="center"> <P STYLE="margin-top:0pt; margin-bottom:0pt; font-size:8pt; font-family:Times New Roman" ALIGN="center"><B>Exhibit</B></P>
<P STYLE="margin-top:0pt; margin-bottom:1pt; border-bottom:1.00pt solid #000000; width:28.45pt; font-size:8pt; font-family:Times New Roman" ALIGN="center"><B>Number</B></P></TD>
<TD VALIGN="bottom">&nbsp;&nbsp;</TD>
<TD VALIGN="bottom" NOWRAP ALIGN="center"> <P STYLE="border-bottom:1.00pt solid #000000; width:39.50pt; font-size:8pt; font-family:Times New Roman" ALIGN="center"><B>Description</B></P></TD></TR>


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<TD VALIGN="top" NOWRAP ALIGN="center">99.1</TD>
<TD VALIGN="bottom">&nbsp;&nbsp;</TD>
<TD VALIGN="top">Press Release titled &#147;ARCA biopharma Announces IND Submission to U.S. FDA for Gencaro for the Treatment of Atrial Fibrillation&#148; dated October 29, 2013.</TD></TR>
</TABLE>

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 <P STYLE="margin-top:0pt; margin-bottom:0pt; font-size:10pt; font-family:Times New Roman" ALIGN="center"><B>SIGNATURES </B></P>
<P STYLE="margin-top:12pt; margin-bottom:0pt; text-indent:4%; font-size:10pt; font-family:Times New Roman">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. </P> <P STYLE="margin-top:12pt; margin-bottom:0pt; font-size:10pt; font-family:Times New Roman">Dated: October&nbsp;29, 2013 </P>
<P STYLE="font-size:12pt;margin-top:0pt;margin-bottom:0pt">&nbsp;</P><DIV ALIGN="right">
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<TD VALIGN="top" COLSPAN="3"> <P STYLE="margin-top:0pt; margin-bottom:0pt; font-size:10pt; font-family:Times New Roman"><B>ARCA biopharma, Inc.</B></P>
<P STYLE="margin-top:0pt; margin-bottom:1pt; font-size:10pt; font-family:Times New Roman">(Registrant)</P></TD></TR>
<TR>
<TD HEIGHT="16"></TD>
<TD HEIGHT="16" COLSPAN="2"></TD></TR>
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<TD VALIGN="top">By:</TD>
<TD VALIGN="bottom"><FONT STYLE="font-size:8pt">&nbsp;</FONT></TD>
<TD VALIGN="bottom"> <P STYLE="margin-top:0pt; margin-bottom:1pt; border-bottom:1px solid #000000; font-size:10pt; font-family:Times New Roman">/s/ Christopher D. Ozeroff</P></TD></TR>
<TR STYLE="font-family:Times New Roman; font-size:10pt">
<TD VALIGN="top">Name:</TD>
<TD VALIGN="bottom"><FONT STYLE="font-size:8pt">&nbsp;</FONT></TD>
<TD VALIGN="bottom">Christopher D. Ozeroff</TD></TR>
<TR STYLE="font-family:Times New Roman; font-size:10pt">
<TD VALIGN="top">Title:</TD>
<TD VALIGN="bottom"><FONT STYLE="font-size:8pt">&nbsp;</FONT></TD>
<TD VALIGN="bottom">SVP and General Counsel</TD></TR>
</TABLE></DIV>

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 <P STYLE="margin-top:0pt; margin-bottom:0pt; font-size:10pt; font-family:Times New Roman" ALIGN="center"><B>INDEX TO EXHIBITS </B></P>
<P STYLE="font-size:12pt;margin-top:0pt;margin-bottom:0pt">&nbsp;</P>
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<TD VALIGN="bottom" NOWRAP ALIGN="center"> <P STYLE="border-bottom:1.00pt solid #000000; width:28.45pt; font-size:8pt; font-family:Times New Roman" ALIGN="center"><B>Exhibit<BR>Number</B></P></TD>
<TD VALIGN="bottom">&nbsp;&nbsp;</TD>
<TD VALIGN="bottom" NOWRAP ALIGN="center"> <P STYLE="border-bottom:1.00pt solid #000000; width:39.50pt; font-size:8pt; font-family:Times New Roman" ALIGN="center"><B>Description</B></P></TD></TR>


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<TD VALIGN="top" NOWRAP ALIGN="center">99.1</TD>
<TD VALIGN="bottom">&nbsp;&nbsp;</TD>
<TD VALIGN="top">Press Release titled &#147;ARCA biopharma Announces IND Submission to U.S. FDA for Gencaro for the Treatment of Atrial Fibrillation&#148; dated October 29, 2013.</TD></TR>
</TABLE>
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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): October 29, 2013 (October 29, 2013)
ARCA biopharma, Inc.
(Exact Name of Registrant as Specified in Charter)
Delaware
000-22873
36-3855489
(State or Other Jurisdiction
of Incorporation)
(Commission
File Number)
(I.R.S. Employer
Identification No.)
11080 CirclePoint Road, Suite 140, Westminster, CO 80020
(Address of Principal Executive Offices) (Zip Code)
(720) 940-2200
(Registrant's telephone number, including area code)
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 (see General Instruction A.2. below):
¨
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))
Section 8 — Other Events
Item 8.01. Other Events.
On
October 29, 2013, ARCA biopharma, Inc. announced that it submitted an Investigational New Drug (IND) application to the U.S. Food and Drug Administration for the GENETIC-AF clinical trial of Gencaro (bucindolol hydrochloride), a
pharmacologically unique beta-blocker and mild vasodilator being developed for atrial fibrillation, and has established the Data Safety Monitoring Board for GENETIC-AF. The press release is furnished as Exhibit 99.1 hereto, the contents of which are
incorporated herein by reference.
Section 9 — Financial Statements and Exhibits
Item 9.01. Financial Statements and Exhibits.
(d)
Exhibits.
Exhibit
Number
Description
99.1
Press Release titled "ARCA biopharma Announces IND Submission to U.S. FDA for Gencaro for the Treatment of Atrial Fibrillation" dated October 29, 2013.
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.
Dated: October 29, 2013
ARCA biopharma, Inc.
(Registrant)
By:
/s/ Christopher D. Ozeroff
Name:
Christopher D. Ozeroff
Title:
SVP and General Counsel
INDEX TO EXHIBITS
Exhibit
Number
Description
99.1
Press Release titled "ARCA biopharma Announces IND Submission to U.S. FDA for Gencaro for the Treatment of Atrial Fibrillation" dated October 29, 2013.