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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:3pt; margin-bottom:0pt; font-size:14pt; 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:6pt;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:6pt; margin-bottom:0pt; font-size:18pt; font-family:Times New Roman" ALIGN="center"><B>FORM 8-K
</B></P> <P STYLE="font-size:6pt;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" ALIGN="center"><B>CURRENT REPORT </B></P>
<P STYLE="margin-top:12pt; margin-bottom:0pt; font-size:10pt; font-family:Times New Roman" ALIGN="center"><B>Pursuant to Section&nbsp;13 or 15(d) of the </B></P>
<P STYLE="margin-top:0pt; margin-bottom:0pt; font-size:10pt; font-family:Times New Roman" ALIGN="center"><B>Securities Exchange Act of 1934 </B></P>
<P STYLE="margin-top:12pt; margin-bottom:0pt; font-size:10pt; font-family:Times New Roman" ALIGN="center"><B>Date of Report (Date of earliest event reported): September&nbsp;27, 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>Achillion Pharmaceuticals, Inc. </B></P>
<P STYLE="margin-top:0pt; margin-bottom:0pt; font-size:8pt; font-family:Times New Roman" ALIGN="center"><B>(Exact name of registrant as specified in its charter) </B></P> <P STYLE="font-size:6pt;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>001-33095</B></TD>
<TD VALIGN="bottom">&nbsp;</TD>
<TD VALIGN="top" ALIGN="center"><B>52-2113479</B></TD></TR>
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<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>(IRS 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="font-size:12pt;margin-top:0pt;margin-bottom:0pt">&nbsp;</P>
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<TD VALIGN="top" ALIGN="center"> <P STYLE="margin-top:0pt; margin-bottom:0pt; font-size:10pt; font-family:Times New Roman" ALIGN="center"><B>300 George Street</B></P>
<P STYLE="margin-top:0pt; margin-bottom:1pt; font-size:10pt; font-family:Times New Roman" ALIGN="center"><B>New Haven, CT</B></P></TD>
<TD VALIGN="bottom">&nbsp;</TD>
<TD VALIGN="bottom" ALIGN="center"><B>06511</B></TD></TR>
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<TD VALIGN="top" ALIGN="center"><B>(Address of principal executive offices)</B></TD>
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<TD VALIGN="top" ALIGN="center"><B>(Zip Code)</B></TD></TR>
</TABLE> <P STYLE="margin-top:12pt; margin-bottom:0pt; font-size:10pt; font-family:Times New Roman" ALIGN="center"><B>Registrant&#146;s telephone number, including area code: <U>(203)&nbsp;624-7000</U></B> </P>
<P STYLE="margin-top:12pt; margin-bottom:0pt; font-size:10pt; font-family:Times New Roman" ALIGN="center"><B>N/A </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; text-indent:4%; font-size:10pt; font-family:Times New Roman">Check the
appropriate box if the Form 8-K is intended to simultaneously satisfy the filing obligation of the registrant under any of the following provisions: </P> <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">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>
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<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>
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<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:12pt;margin-top:0pt;margin-bottom:0pt">&nbsp;</P>
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 <P STYLE="margin-top:0pt; 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:4%; font-size:10pt; font-family:Times New Roman">Achillion Pharmaceuticals, Inc. (the &#147;Company&#148;) announced today that the Company received a response from the U. S. Food and Drug
Administration (the &#147;FDA&#148;), on the clinical hold related to sovaprevir, the Company&#146;s NS3 protease inhibitor. The FDA response indicated that, while the Company&#146;s submission addressed all issues noted in the FDA&#146;s
June&nbsp;29, 2013 letter, the FDA concluded that the removal of the clinical hold is not warranted. </P> <P STYLE="margin-top:12pt; margin-bottom:0pt; text-indent:4%; font-size:10pt; font-family:Times New Roman">The Company also announced interim
data from the ongoing -007 Phase 2a clinical trial evaluating two doses of sovaprevir, either 200 mg or 400 mg once daily, in combination with 50 mg once daily of ACH-3102 and ribavirin twice daily for 12 weeks in patients with treatment-na&iuml;ve
GT 1a or 1b hepatitis HCV. </P> <P STYLE="margin-top:12pt; margin-bottom:0pt; text-indent:4%; font-size:10pt; font-family:Times New Roman">The full text of the press release issued in connection with this announcement is attached as Exhibit 99.1 to
this Current report on Form 8-K. </P> <P STYLE="margin-top:18pt; margin-bottom:0pt; font-size:10pt; font-family:Times New Roman"><B>Item&nbsp;9.01. Financial Statements and Exhibits </B></P>
<P STYLE="font-size:6pt;margin-top:0pt;margin-bottom:0pt">&nbsp;</P>
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<TD WIDTH="4%" VALIGN="top" ALIGN="left">(d)</TD>
<TD ALIGN="left" VALIGN="top">Exhibits </TD></TR></TABLE> <P STYLE="margin-top:12pt; margin-bottom:0pt; margin-left:4%; text-indent:4%; font-size:10pt; font-family:Times New Roman">The following exhibit relating to Item&nbsp;8.01 shall be deemed to
be furnished, and not filed: </P> <P STYLE="font-size:12pt;margin-top:0pt;margin-bottom:0pt">&nbsp;</P>
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<TD WIDTH="5%" VALIGN="top" ALIGN="left">99.1</TD>
<TD ALIGN="left" VALIGN="top">&nbsp;&nbsp;&nbsp;&nbsp;Press Release dated September&nbsp;27, 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">SIGNATURE </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, as amended, the registrant has duly caused this report to be signed on
its behalf by the undersigned hereunto duly authorized. </P> <P STYLE="font-size:12pt;margin-top:0pt;margin-bottom:0pt">&nbsp;</P>
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<TD VALIGN="top" COLSPAN="3">ACHILLION PHARMACEUTICALS, INC.</TD></TR>
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<TD VALIGN="top" COLSPAN="3">Date: September&nbsp;27, 2013</TD>
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<TD VALIGN="top">By:</TD>
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<TD VALIGN="top" STYLE="BORDER-BOTTOM:1px solid #000000">/s/ Mary Kay Fenton</TD></TR>
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<TD VALIGN="bottom"> <P STYLE="margin-top:0pt; margin-bottom:0pt; font-size:10pt; font-family:Times New Roman">Mary Kay Fenton</P> <P STYLE="margin-top:0pt; margin-bottom:1pt; font-size:10pt; font-family:Times New Roman">Chief Financial
Officer</P></TD></TR>
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 <P STYLE="margin-top:0pt; margin-bottom:0pt; font-size:10pt; font-family:Times New Roman" ALIGN="center">Exhibit Index </P> <P STYLE="font-size:12pt;margin-top:0pt;margin-bottom:0pt">&nbsp;</P>
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<TD WIDTH="4%" VALIGN="top" ALIGN="left">99.1</TD>
<TD ALIGN="left" VALIGN="top">&nbsp;&nbsp;&nbsp;&nbsp;Press Release dated September&nbsp;27, 2013 </TD></TR></TABLE>
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Form 8-K
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): September 27, 2013
Achillion Pharmaceuticals, Inc.
(Exact name of registrant as specified in its charter)
Delaware
001-33095
52-2113479
(State or other jurisdiction
of incorporation)
(Commission
File Number)
(IRS Employer
Identification No.)
300 George Street
New Haven, CT
06511
(Address of principal executive offices)
(Zip Code)
Registrant's telephone number, including area code:
(203) 624-7000
N/A
(Former name or
former address, if changed since last report)
Check the
appropriate box if the Form 8-K 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)).
Item 8.01. Other Events
Achillion Pharmaceuticals, Inc. (the "Company") announced today that the Company received a response from the U. S. Food and Drug
Administration (the "FDA"), on the clinical hold related to sovaprevir, the Company's NS3 protease inhibitor. The FDA response indicated that, while the Company's submission addressed all issues noted in the FDA's
June 29, 2013 letter, the FDA concluded that the removal of the clinical hold is not warranted.
The Company also announced interim
data from the ongoing -007 Phase 2a clinical trial evaluating two doses of sovaprevir, either 200 mg or 400 mg once daily, in combination with 50 mg once daily of ACH-3102 and ribavirin twice daily for 12 weeks in patients with treatment-naïve
GT 1a or 1b hepatitis HCV.
The full text of the press release issued in connection with this announcement is attached as Exhibit 99.1 to
this Current report on Form 8-K.
Item 9.01. Financial Statements and Exhibits
(d)
Exhibits
The following exhibit relating to Item 8.01 shall be deemed to
be furnished, and not filed:
99.1
Press Release dated September 27, 2013
SIGNATURE
Pursuant to the requirements of the Securities Exchange Act of 1934, as amended, the registrant has duly caused this report to be signed on
its behalf by the undersigned hereunto duly authorized.
ACHILLION PHARMACEUTICALS, INC.
Date: September 27, 2013
By:
/s/ Mary Kay Fenton
Mary Kay Fenton
Chief Financial
Officer
Exhibit Index
99.1
Press Release dated September 27, 2013