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 <P STYLE="margin-top:0pt; margin-bottom:0pt; font-size:10pt; font-family:Times New Roman" ALIGN="center"><B>As filed with the U.S. Securities and Exchange Commission on May&nbsp;11, 2015 </B></P>
<P STYLE="margin-top:0pt; margin-bottom:0pt; font-size:10pt; font-family:Times New Roman" ALIGN="right"><B>Registration No.&nbsp;333-&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; </B></P>
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<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 S-8
</B></P> <P STYLE="margin-top:0pt; margin-bottom:0pt; font-size:18pt; font-family:Times New Roman" ALIGN="center"><B>REGISTRATION STATEMENT </B></P>
<P STYLE="margin-top:0pt; margin-bottom:0pt; font-size:12pt; font-family:Times New Roman" ALIGN="center"><B><I>UNDER </I></B></P> <P STYLE="margin-top:0pt; margin-bottom:0pt; font-size:12pt; font-family:Times New Roman" ALIGN="center"><B><I>THE
SECURITIES ACT OF 1933 </I></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>Calithera Biosciences, 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 its 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"></TD>
<TD VALIGN="top" ALIGN="center"><B>27-2366329</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 of</B></P>
<P STYLE="margin-top:0pt; margin-bottom:1pt; font-size:8pt; font-family:Times New Roman" ALIGN="center"><B>Incorporation or organization)</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>343 Oyster Point Blvd., Suite 200 </B></P>
<P STYLE="margin-top:0pt; margin-bottom:0pt; font-size:10pt; font-family:Times New Roman" ALIGN="center"><B>South San Francisco, California 94080 </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>Calithera Biosciences, Inc. 2014 Equity Incentive Plan </B></P>
<P STYLE="margin-top:0pt; margin-bottom:0pt; font-size:10pt; font-family:Times New Roman" ALIGN="center"><B>Calithera Biosciences, Inc. 2014 Employee Stock Purchase Plan </B></P>
<P STYLE="margin-top:0pt; margin-bottom:0pt; font-size:8pt; font-family:Times New Roman" ALIGN="center"><B>(Full title of the plans) </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" ALIGN="center"><B>Susan M.
Molineaux, Ph.D. </B></P> <P STYLE="margin-top:0pt; margin-bottom:0pt; font-size:10pt; font-family:Times New Roman" ALIGN="center"><B>President and Chief Executive Officer </B></P>
<P STYLE="margin-top:0pt; margin-bottom:0pt; font-size:10pt; font-family:Times New Roman" ALIGN="center"><B>343 Oyster Point Blvd., Suite 200 </B></P>
<P STYLE="margin-top:0pt; margin-bottom:0pt; font-size:10pt; font-family:Times New Roman" ALIGN="center"><B>South San Francisco, California 94080 </B></P>
<P STYLE="margin-top:0pt; margin-bottom:0pt; font-size:10pt; font-family:Times New Roman" ALIGN="center"><B>(650) 870-1000 </B></P> <P STYLE="margin-top:0pt; margin-bottom:0pt; font-size:8pt; font-family:Times New Roman" ALIGN="center"><B>(Name and
address of agent for service) (Telephone number, including area code, of agent for service) </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" ALIGN="center"><B><I>Copies to:
</I></B></P> <P STYLE="margin-top:6pt; margin-bottom:0pt; font-size:10pt; font-family:Times New Roman" ALIGN="center"><B>Barbara A. Kosacz </B></P>
<P STYLE="margin-top:0pt; margin-bottom:0pt; font-size:10pt; font-family:Times New Roman" ALIGN="center"><B>John T. McKenna </B></P> <P STYLE="margin-top:0pt; margin-bottom:0pt; font-size:10pt; font-family:Times New Roman" ALIGN="center"><B>Danielle
E. Naftulin </B></P> <P STYLE="margin-top:0pt; margin-bottom:0pt; font-size:10pt; font-family:Times New Roman" ALIGN="center"><B>Cooley LLP </B></P>
<P STYLE="margin-top:0pt; margin-bottom:0pt; font-size:10pt; font-family:Times New Roman" ALIGN="center"><B>3175 Hanover Street </B></P> <P STYLE="margin-top:0pt; margin-bottom:0pt; font-size:10pt; font-family:Times New Roman" ALIGN="center"><B>Palo
Alto, California 94304 </B></P> <P STYLE="margin-top:0pt; margin-bottom:0pt; font-size:10pt; font-family:Times New Roman" ALIGN="center"><B>(650) 843-5000 </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">Indicate by check mark whether
the registrant is a large accelerated filer, an accelerated filer, a non-accelerated filer, or a smaller reporting company. See the definitions of &#147;large accelerated filer,&#148; &#147;accelerated filer&#148; and &#147;smaller reporting
company&#148; in Rule 12b-2 of the Exchange Act. </P> <P STYLE="font-size:12pt;margin-top:0pt;margin-bottom:0pt">&nbsp;</P>
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<TD VALIGN="bottom">Large&nbsp;accelerated&nbsp;filer</TD>
<TD VALIGN="bottom">&nbsp;</TD>
<TD VALIGN="bottom"><FONT STYLE="FONT-FAMILY:WINGDINGS">&#168;</FONT></TD>
<TD VALIGN="bottom">&nbsp;&nbsp;</TD>
<TD VALIGN="bottom">Accelerated&nbsp;filer</TD>
<TD VALIGN="bottom">&nbsp;</TD>
<TD VALIGN="bottom"><FONT STYLE="FONT-FAMILY:WINGDINGS">&#168;</FONT></TD></TR>
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<TD HEIGHT="8"></TD>
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<TD HEIGHT="8" COLSPAN="2"></TD>
<TD HEIGHT="8" COLSPAN="2"></TD></TR>
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<TD VALIGN="bottom">Non-accelerated filer</TD>
<TD VALIGN="bottom">&nbsp;</TD>
<TD VALIGN="bottom"><FONT STYLE="FONT-FAMILY:WINGDINGS">&#120;</FONT>&nbsp;&nbsp;(Do not check if a smaller reporting company)</TD>
<TD VALIGN="bottom">&nbsp;&nbsp;</TD>
<TD VALIGN="bottom">Smaller&nbsp;reporting&nbsp;company</TD>
<TD VALIGN="bottom">&nbsp;</TD>
<TD VALIGN="bottom"><FONT STYLE="FONT-FAMILY:WINGDINGS">&#168;</FONT></TD></TR>
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<P STYLE="margin-top:12pt; margin-bottom:0pt; font-size:10pt; font-family:Times New Roman" ALIGN="center"><B>CALCULATION OF REGISTRATION FEE </B></P> <P STYLE="font-size:4pt;margin-top:0pt;margin-bottom:0pt">&nbsp;</P>
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<TD COLSPAN="9" VALIGN="bottom"> <P STYLE="border-top:1.00px solid #000000">&nbsp;</P></TD></TR>
<TR STYLE="font-family:Times New Roman; font-size:8pt">
<TD VALIGN="bottom" ALIGN="center" STYLE="BORDER-TOP:1px solid #000000"> <P STYLE="margin-top:0pt; margin-bottom:0pt; font-size:8pt; font-family:Times New Roman" ALIGN="center"><B>Title of Securities</B></P>
<P STYLE="margin-top:0pt; margin-bottom:1pt; font-size:8pt; font-family:Times New Roman" ALIGN="center"><B>to be Registered</B></P></TD>
<TD VALIGN="bottom" STYLE="BORDER-LEFT:1px solid #000000; BORDER-TOP:1px solid #000000">&nbsp;</TD>
<TD VALIGN="bottom" NOWRAP ALIGN="center" STYLE="BORDER-TOP:1px solid #000000"> <P STYLE="margin-top:0pt; margin-bottom:0pt; font-size:8pt; font-family:Times New Roman" ALIGN="center"><B>Amount<BR></B></P>
<P STYLE="margin-top:0pt; margin-bottom:1pt; font-size:8pt; font-family:Times New Roman" ALIGN="center"><B>to be<BR>Registered(1)</B></P></TD>
<TD VALIGN="bottom" STYLE="BORDER-LEFT:1px solid #000000; BORDER-TOP:1px solid #000000">&nbsp;</TD>
<TD VALIGN="bottom" NOWRAP ALIGN="center" STYLE="BORDER-TOP:1px solid #000000"><B>Proposed<BR>Maximum<BR>Offering Price<BR>per Share(2)</B></TD>
<TD VALIGN="bottom" STYLE="BORDER-LEFT:1px solid #000000; BORDER-TOP:1px solid #000000">&nbsp;</TD>
<TD VALIGN="bottom" NOWRAP ALIGN="center" STYLE="BORDER-TOP:1px solid #000000"> <P STYLE="margin-top:0pt; margin-bottom:0pt; font-size:8pt; font-family:Times New Roman" ALIGN="center"><B>Proposed<BR>Maximum<BR>Aggregate</B></P>
<P STYLE="margin-top:0pt; margin-bottom:1pt; font-size:8pt; font-family:Times New Roman" ALIGN="center"><B>&nbsp;&nbsp;Offering&nbsp;Price(2)&nbsp;&nbsp;</B></P></TD>
<TD VALIGN="bottom" STYLE="BORDER-LEFT:1px solid #000000; BORDER-TOP:1px solid #000000">&nbsp;</TD>
<TD VALIGN="bottom" NOWRAP ALIGN="center" STYLE="BORDER-TOP:1px solid #000000"> <P STYLE="margin-top:0pt; margin-bottom:0pt; font-size:8pt; font-family:Times New Roman" ALIGN="center"><B>Amount&nbsp;of</B></P>
<P STYLE="margin-top:0pt; margin-bottom:1pt; font-size:8pt; font-family:Times New Roman" ALIGN="center"><B>Registration&nbsp;Fee</B></P></TD></TR>
<TR STYLE="font-family:Times New Roman; font-size:10pt">
<TD VALIGN="top" STYLE="BORDER-TOP:1px solid #000000"> <P STYLE="margin-left:1.00em; text-indent:-1.00em; font-size:10pt; font-family:Times New Roman">Common Stock, par value $0.0001 per share</P></TD>
<TD VALIGN="bottom" STYLE="BORDER-LEFT:1px solid #000000; BORDER-TOP:1px solid #000000">&nbsp;</TD>
<TD VALIGN="bottom" STYLE="BORDER-TOP:1px solid #000000"><FONT SIZE="1">&nbsp;</FONT></TD>
<TD VALIGN="bottom" STYLE="BORDER-LEFT:1px solid #000000; BORDER-TOP:1px solid #000000">&nbsp;</TD>
<TD VALIGN="bottom" STYLE="BORDER-TOP:1px solid #000000"><FONT SIZE="1">&nbsp;</FONT></TD>
<TD VALIGN="bottom" STYLE="BORDER-LEFT:1px solid #000000; BORDER-TOP:1px solid #000000">&nbsp;</TD>
<TD VALIGN="bottom" STYLE="BORDER-TOP:1px solid #000000"><FONT SIZE="1">&nbsp;</FONT></TD>
<TD VALIGN="bottom" STYLE="BORDER-LEFT:1px solid #000000; BORDER-TOP:1px solid #000000">&nbsp;</TD>
<TD VALIGN="bottom" STYLE="BORDER-TOP:1px solid #000000"><FONT SIZE="1">&nbsp;</FONT></TD></TR>
<TR STYLE="font-family:Times New Roman; font-size:10pt">
<TD VALIGN="top" STYLE="BORDER-TOP:1px solid #000000"> <P STYLE="margin-left:3.00em; text-indent:-1.00em; font-size:10pt; font-family:Times New Roman">&#150; 2014 Equity Incentive Plan</P></TD>
<TD VALIGN="bottom" STYLE="BORDER-LEFT:1px solid #000000; BORDER-TOP:1px solid #000000">&nbsp;</TD>
<TD VALIGN="bottom" NOWRAP ALIGN="center" STYLE="BORDER-TOP:1px solid #000000">717,735</TD>
<TD VALIGN="bottom" STYLE="BORDER-LEFT:1px solid #000000; BORDER-TOP:1px solid #000000">&nbsp;</TD>
<TD VALIGN="bottom" NOWRAP ALIGN="center" STYLE="BORDER-TOP:1px solid #000000">$9.275</TD>
<TD VALIGN="bottom" STYLE="BORDER-LEFT:1px solid #000000; BORDER-TOP:1px solid #000000">&nbsp;</TD>
<TD VALIGN="bottom" NOWRAP ALIGN="center" STYLE="BORDER-TOP:1px solid #000000">$6,656,992.13</TD>
<TD VALIGN="bottom" STYLE="BORDER-LEFT:1px solid #000000; BORDER-TOP:1px solid #000000">&nbsp;</TD>
<TD VALIGN="bottom" NOWRAP ALIGN="center" STYLE="BORDER-TOP:1px solid #000000">$773.55</TD></TR>
<TR STYLE="font-family:Times New Roman; font-size:10pt">
<TD VALIGN="top" STYLE="BORDER-TOP:1px solid #000000"> <P STYLE="margin-left:3.00em; text-indent:-1.00em; font-size:10pt; font-family:Times New Roman">&#150; 2014 Employee Stock Purchase Plan</P></TD>
<TD VALIGN="bottom" STYLE="BORDER-LEFT:1px solid #000000; BORDER-TOP:1px solid #000000">&nbsp;</TD>
<TD VALIGN="bottom" NOWRAP ALIGN="center" STYLE="BORDER-TOP:1px solid #000000">179,433</TD>
<TD VALIGN="bottom" STYLE="BORDER-LEFT:1px solid #000000; BORDER-TOP:1px solid #000000">&nbsp;</TD>
<TD VALIGN="bottom" NOWRAP ALIGN="center" STYLE="BORDER-TOP:1px solid #000000">$9.275</TD>
<TD VALIGN="bottom" STYLE="BORDER-LEFT:1px solid #000000; BORDER-TOP:1px solid #000000">&nbsp;</TD>
<TD VALIGN="bottom" NOWRAP ALIGN="center" STYLE="BORDER-TOP:1px solid #000000">$1,664,241.08</TD>
<TD VALIGN="bottom" STYLE="BORDER-LEFT:1px solid #000000; BORDER-TOP:1px solid #000000">&nbsp;</TD>
<TD VALIGN="bottom" NOWRAP ALIGN="center" STYLE="BORDER-TOP:1px solid #000000">$193.39</TD></TR>
<TR STYLE="font-family:Times New Roman; font-size:10pt">
<TD VALIGN="top" STYLE="BORDER-TOP:1px solid #000000"> <P STYLE="margin-left:1.00em; text-indent:-1.00em; font-size:10pt; font-family:Times New Roman">Total</P></TD>
<TD VALIGN="bottom" STYLE="BORDER-LEFT:1px solid #000000; BORDER-TOP:1px solid #000000">&nbsp;</TD>
<TD VALIGN="bottom" NOWRAP ALIGN="center" STYLE="BORDER-TOP:1px solid #000000">897,168</TD>
<TD VALIGN="bottom" STYLE="BORDER-LEFT:1px solid #000000; BORDER-TOP:1px solid #000000">&nbsp;</TD>
<TD VALIGN="bottom" STYLE="BORDER-TOP:1px solid #000000"><FONT SIZE="1">&nbsp;</FONT></TD>
<TD VALIGN="bottom" STYLE="BORDER-LEFT:1px solid #000000; BORDER-TOP:1px solid #000000">&nbsp;</TD>
<TD VALIGN="bottom" NOWRAP ALIGN="center" STYLE="BORDER-TOP:1px solid #000000">$8,321,233.21</TD>
<TD VALIGN="bottom" STYLE="BORDER-LEFT:1px solid #000000; BORDER-TOP:1px solid #000000">&nbsp;</TD>
<TD VALIGN="bottom" NOWRAP ALIGN="center" STYLE="BORDER-TOP:1px solid #000000">$966.94</TD></TR>
<TR STYLE="font-size:1px; ">
<TD COLSPAN="9" VALIGN="bottom"> <P STYLE="border-top:1.00px solid #000000">&nbsp;</P></TD></TR>
<TR STYLE="font-size:1px; ">
<TD COLSPAN="9" VALIGN="bottom"> <P STYLE="border-top:1.00px solid #000000">&nbsp;</P></TD></TR>
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<TD WIDTH="5%" VALIGN="top" ALIGN="left">(1)</TD>
<TD ALIGN="left" VALIGN="top">Pursuant to Rule 416(a) under the Securities Act of 1933, as amended, this Registration Statement shall also cover any additional shares of common stock of Calithera Biosciences, Inc. that become issuable under the 2014
Equity Incentive Plan, and the 2014 Employee Stock Purchase Plan set forth herein by reason of any stock dividend, stock split, recapitalization, or other similar transaction effected that results in an increase to the number of outstanding shares
of the Registrant&#146;s common stock. </TD></TR></TABLE>
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<TD WIDTH="5%" VALIGN="top" ALIGN="left">(2)</TD>
<TD ALIGN="left" VALIGN="top">Estimated in accordance with Rule 457(c) and (h)&nbsp;under the Securities Act solely for the purpose of calculating the registration fee on the basis of $9.275, the average of the high and low prices of the
Registrant&#146;s common stock as reported on The NASDAQ Global Market on May&nbsp;6, 2015. </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" ALIGN="center"><B>EXPLANATORY NOTE </B></P>
<P STYLE="margin-top:12pt; margin-bottom:0pt; text-indent:4%; font-size:10pt; font-family:Times New Roman">Calithera Biosciences, Inc. (the &#147;<B><I>Registrant</I></B>&#148;) is filing this Registration Statement on Form&nbsp;S-8 for the purpose
of registering an additional (a)&nbsp;717,735 shares of its common stock, par value $0.0001 per share (the &#147;<B><I>Common Stock</I></B>&#148;), issuable to eligible persons under the 2014 Equity Incentive Plan, which Common Stock is in addition
to the shares of Common Stock registered on the Registrant&#146;s Form&nbsp;S-8 filed on October&nbsp;2, 2014 (File No.&nbsp;333-199126) and (the &#147;<B><I>Prior Form S-8</I></B>&#148;) and (b)&nbsp;179,433 shares of Common Stock issuable to
eligible persons under the 2014 Employee Stock Purchase Plan, which Common Stock is in addition to the shares of Common Stock registered on the Prior Form S-8. </P>
<P STYLE="margin-top:24pt; margin-bottom:0pt; font-size:10pt; font-family:Times New Roman" ALIGN="center"><B>PART II </B></P> <P STYLE="font-size:12pt;margin-top:0pt;margin-bottom:0pt">&nbsp;</P>
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<TD WIDTH="10%" VALIGN="top" ALIGN="left"><B>ITEM&nbsp;3.</B></TD>
<TD ALIGN="left" VALIGN="top"><B>INCORPORATION OF CERTAIN DOCUMENTS BY REFERENCE </B></TD></TR></TABLE> <P STYLE="margin-top:6pt; margin-bottom:0pt; text-indent:4%; font-size:10pt; font-family:Times New Roman">Pursuant to General Instruction E to
Form S-8, the contents of the Prior Form S-8 are incorporated by reference herein. </P> <P STYLE="margin-top:12pt; margin-bottom:0pt; text-indent:4%; font-size:10pt; font-family:Times New Roman">All other reports and documents subsequently filed by
the Registrant pursuant to Sections 13(a), 13(c), 14 and 15(d) of the Exchange Act (other than Current Reports furnished under Item&nbsp;2.02 or Item&nbsp;7.01 of Form 8-K and exhibits furnished on such form that relate to such items) on or after
the date of this Registration Statement and prior to the filing of a post-effective amendment to this Registration Statement which indicates that all securities offered have been sold or which deregisters all securities then remaining unsold, shall
be deemed to be incorporated by reference herein and to be a part of this Registration Statement from the date of the filing of such reports and documents. Any statement contained in a document incorporated or deemed to be incorporated by reference
herein shall be deemed to be modified or superseded for purposes of this Registration Statement to the extent that a statement contained herein or in any subsequently filed document that also is deemed to be incorporated by reference herein modifies
or supersedes such statement. Any such statement so modified or superseded shall not be deemed, except as so modified or superseded, to constitute a part of this Registration Statement. </P>
<P STYLE="font-size:18pt;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="10%" VALIGN="top" ALIGN="left"><B>ITEM&nbsp;8.</B></TD>
<TD ALIGN="left" VALIGN="top"><B>EXHIBITS </B></TD></TR></TABLE> <P STYLE="font-size:12pt;margin-top:0pt;margin-bottom:0pt">&nbsp;</P>
<TABLE CELLSPACING="0" CELLPADDING="0" WIDTH="100%" BORDER="0" STYLE="BORDER-COLLAPSE:COLLAPSE; font-family:Times New Roman; font-size:10pt" ALIGN="center">


<TR>
<TD></TD>
<TD VALIGN="bottom" WIDTH="3%"></TD>
<TD WIDTH="54%"></TD>
<TD VALIGN="bottom" WIDTH="3%"></TD>
<TD></TD>
<TD VALIGN="bottom" WIDTH="3%"></TD>
<TD></TD>
<TD VALIGN="bottom" WIDTH="3%"></TD>
<TD></TD>
<TD VALIGN="bottom" WIDTH="3%"></TD>
<TD></TD></TR>
<TR STYLE="font-family:Times New Roman; font-size:8pt">
<TD VALIGN="bottom">&nbsp;</TD>
<TD VALIGN="bottom">&nbsp;&nbsp;</TD>
<TD VALIGN="bottom">&nbsp;</TD>
<TD VALIGN="bottom">&nbsp;&nbsp;</TD>
<TD VALIGN="bottom" COLSPAN="5" ALIGN="center" STYLE="border-bottom:1.00pt solid #000000"><B>Incorporated&nbsp;by&nbsp;Reference</B></TD>
<TD VALIGN="bottom">&nbsp;&nbsp;</TD>
<TD VALIGN="bottom">&nbsp;</TD></TR>
<TR STYLE="font-family:Times New Roman; font-size:8pt">
<TD VALIGN="bottom" 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" ALIGN="center" STYLE="border-bottom:1.00pt solid #000000"> <P STYLE="margin-top:0pt; margin-bottom:1pt; font-size:8pt; font-family:Times New Roman" ALIGN="center"><B>Description</B></P></TD>
<TD VALIGN="bottom">&nbsp;&nbsp;</TD>
<TD VALIGN="bottom" ALIGN="center" STYLE="border-bottom:1.00pt solid #000000"><B>Schedule</B><br><B>Form</B></TD>
<TD VALIGN="bottom">&nbsp;&nbsp;</TD>
<TD VALIGN="bottom" ALIGN="center" STYLE="border-bottom:1.00pt solid #000000"><B>File</B><br><B>Number</B></TD>
<TD VALIGN="bottom">&nbsp;&nbsp;</TD>
<TD VALIGN="bottom" ALIGN="center" STYLE="border-bottom:1.00pt solid #000000"><B>&nbsp;&nbsp;Exhibit&nbsp;&nbsp;</B></TD>
<TD VALIGN="bottom">&nbsp;&nbsp;</TD>
<TD VALIGN="bottom" ALIGN="center" STYLE="border-bottom:1.00pt solid #000000"><B>&nbsp;&nbsp;Filing&nbsp;Date&nbsp;&nbsp;</B></TD></TR>


<TR STYLE="font-size:1pt">
<TD HEIGHT="8"></TD>
<TD HEIGHT="8" COLSPAN="2"></TD>
<TD HEIGHT="8" COLSPAN="2"></TD>
<TD HEIGHT="8" COLSPAN="2"></TD>
<TD HEIGHT="8" COLSPAN="2"></TD>
<TD HEIGHT="8" COLSPAN="2"></TD></TR>
<TR STYLE="font-family:Times New Roman; font-size:10pt">
<TD VALIGN="top" NOWRAP>&nbsp;&nbsp;4.1</TD>
<TD VALIGN="bottom">&nbsp;&nbsp;</TD>
<TD VALIGN="top">Amended and Restated Certificate of Incorporation of Calithera Biosciences, Inc.</TD>
<TD VALIGN="bottom">&nbsp;&nbsp;</TD>
<TD VALIGN="top" NOWRAP ALIGN="center">8-K</TD>
<TD VALIGN="bottom">&nbsp;&nbsp;</TD>
<TD VALIGN="top" NOWRAP ALIGN="center">001-36644</TD>
<TD VALIGN="bottom">&nbsp;&nbsp;</TD>
<TD VALIGN="top" NOWRAP ALIGN="center">3.1</TD>
<TD VALIGN="bottom">&nbsp;&nbsp;</TD>
<TD VALIGN="top" NOWRAP ALIGN="center">October&nbsp;10,&nbsp;2014</TD></TR>
<TR STYLE="font-size:1pt">
<TD HEIGHT="8"></TD>
<TD HEIGHT="8" COLSPAN="2"></TD>
<TD HEIGHT="8" COLSPAN="2"></TD>
<TD HEIGHT="8" COLSPAN="2"></TD>
<TD HEIGHT="8" COLSPAN="2"></TD>
<TD HEIGHT="8" COLSPAN="2"></TD></TR>
<TR STYLE="font-family:Times New Roman; font-size:10pt">
<TD VALIGN="top" NOWRAP>&nbsp;&nbsp;4.2</TD>
<TD VALIGN="bottom">&nbsp;&nbsp;</TD>
<TD VALIGN="top">Amended and Restated Bylaws of Calithera Biosciences, Inc.</TD>
<TD VALIGN="bottom">&nbsp;&nbsp;</TD>
<TD VALIGN="top" NOWRAP ALIGN="center">S-1</TD>
<TD VALIGN="bottom">&nbsp;&nbsp;</TD>
<TD VALIGN="top" NOWRAP ALIGN="center">333-198-355</TD>
<TD VALIGN="bottom">&nbsp;&nbsp;</TD>
<TD VALIGN="top" NOWRAP ALIGN="center">3.4</TD>
<TD VALIGN="bottom">&nbsp;&nbsp;</TD>
<TD VALIGN="top" NOWRAP ALIGN="center">September&nbsp;19,&nbsp;2014</TD></TR>
<TR STYLE="font-size:1pt">
<TD HEIGHT="8"></TD>
<TD HEIGHT="8" COLSPAN="2"></TD>
<TD HEIGHT="8" COLSPAN="2"></TD>
<TD HEIGHT="8" COLSPAN="2"></TD>
<TD HEIGHT="8" COLSPAN="2"></TD>
<TD HEIGHT="8" COLSPAN="2"></TD></TR>
<TR STYLE="font-family:Times New Roman; font-size:10pt">
<TD VALIGN="top" NOWRAP>&nbsp;&nbsp;4.3</TD>
<TD VALIGN="bottom">&nbsp;&nbsp;</TD>
<TD VALIGN="top">Form of Common Stock Certificate.</TD>
<TD VALIGN="bottom">&nbsp;&nbsp;</TD>
<TD VALIGN="top" NOWRAP ALIGN="center">S-1</TD>
<TD VALIGN="bottom">&nbsp;&nbsp;</TD>
<TD VALIGN="top" NOWRAP ALIGN="center">333-198-355</TD>
<TD VALIGN="bottom">&nbsp;&nbsp;</TD>
<TD VALIGN="top" NOWRAP ALIGN="center">4.1</TD>
<TD VALIGN="bottom">&nbsp;&nbsp;</TD>
<TD VALIGN="top" NOWRAP ALIGN="center">September&nbsp;25,&nbsp;2014</TD></TR>
<TR STYLE="font-size:1pt">
<TD HEIGHT="8"></TD>
<TD HEIGHT="8" COLSPAN="2"></TD>
<TD HEIGHT="8" COLSPAN="2"></TD>
<TD HEIGHT="8" COLSPAN="2"></TD>
<TD HEIGHT="8" COLSPAN="2"></TD>
<TD HEIGHT="8" COLSPAN="2"></TD></TR>
<TR STYLE="font-family:Times New Roman; font-size:10pt">
<TD VALIGN="top" NOWRAP>&nbsp;&nbsp;5.1*</TD>
<TD VALIGN="bottom">&nbsp;&nbsp;</TD>
<TD VALIGN="top">Opinion of Cooley LLP.</TD>
<TD VALIGN="bottom">&nbsp;&nbsp;</TD>
<TD VALIGN="top"></TD>
<TD VALIGN="bottom">&nbsp;&nbsp;</TD>
<TD VALIGN="top"></TD>
<TD VALIGN="bottom">&nbsp;&nbsp;</TD>
<TD VALIGN="top"></TD>
<TD VALIGN="bottom">&nbsp;&nbsp;</TD>
<TD VALIGN="top"></TD></TR>
<TR STYLE="font-size:1pt">
<TD HEIGHT="8"></TD>
<TD HEIGHT="8" COLSPAN="2"></TD>
<TD HEIGHT="8" COLSPAN="2"></TD>
<TD HEIGHT="8" COLSPAN="2"></TD>
<TD HEIGHT="8" COLSPAN="2"></TD>
<TD HEIGHT="8" COLSPAN="2"></TD></TR>
<TR STYLE="font-family:Times New Roman; font-size:10pt">
<TD VALIGN="top" NOWRAP>23.1*</TD>
<TD VALIGN="bottom">&nbsp;&nbsp;</TD>
<TD VALIGN="top">Consent of Independent Registered Public Accounting Firm.</TD>
<TD VALIGN="bottom">&nbsp;&nbsp;</TD>
<TD VALIGN="top"></TD>
<TD VALIGN="bottom">&nbsp;&nbsp;</TD>
<TD VALIGN="top"></TD>
<TD VALIGN="bottom">&nbsp;&nbsp;</TD>
<TD VALIGN="top"></TD>
<TD VALIGN="bottom">&nbsp;&nbsp;</TD>
<TD VALIGN="top"></TD></TR>
<TR STYLE="font-size:1pt">
<TD HEIGHT="8"></TD>
<TD HEIGHT="8" COLSPAN="2"></TD>
<TD HEIGHT="8" COLSPAN="2"></TD>
<TD HEIGHT="8" COLSPAN="2"></TD>
<TD HEIGHT="8" COLSPAN="2"></TD>
<TD HEIGHT="8" COLSPAN="2"></TD></TR>
<TR STYLE="font-family:Times New Roman; font-size:10pt">
<TD VALIGN="top" NOWRAP>23.2*</TD>
<TD VALIGN="bottom">&nbsp;&nbsp;</TD>
<TD VALIGN="top">Consent of Cooley LLP (included in Exhibit&nbsp;5.1).</TD>
<TD VALIGN="bottom">&nbsp;&nbsp;</TD>
<TD VALIGN="top"></TD>
<TD VALIGN="bottom">&nbsp;&nbsp;</TD>
<TD VALIGN="top"></TD>
<TD VALIGN="bottom">&nbsp;&nbsp;</TD>
<TD VALIGN="top"></TD>
<TD VALIGN="bottom">&nbsp;&nbsp;</TD>
<TD VALIGN="top"></TD></TR>
<TR STYLE="font-size:1pt">
<TD HEIGHT="8"></TD>
<TD HEIGHT="8" COLSPAN="2"></TD>
<TD HEIGHT="8" COLSPAN="2"></TD>
<TD HEIGHT="8" COLSPAN="2"></TD>
<TD HEIGHT="8" COLSPAN="2"></TD>
<TD HEIGHT="8" COLSPAN="2"></TD></TR>
<TR STYLE="font-family:Times New Roman; font-size:10pt">
<TD VALIGN="top" NOWRAP>24.1*</TD>
<TD VALIGN="bottom">&nbsp;&nbsp;</TD>
<TD VALIGN="top">Power of Attorney (see signature page hereto).</TD>
<TD VALIGN="bottom">&nbsp;&nbsp;</TD>
<TD VALIGN="top"></TD>
<TD VALIGN="bottom">&nbsp;&nbsp;</TD>
<TD VALIGN="top"></TD>
<TD VALIGN="bottom">&nbsp;&nbsp;</TD>
<TD VALIGN="top"></TD>
<TD VALIGN="bottom">&nbsp;&nbsp;</TD>
<TD VALIGN="top"></TD></TR>
<TR STYLE="font-size:1pt">
<TD HEIGHT="8"></TD>
<TD HEIGHT="8" COLSPAN="2"></TD>
<TD HEIGHT="8" COLSPAN="2"></TD>
<TD HEIGHT="8" COLSPAN="2"></TD>
<TD HEIGHT="8" COLSPAN="2"></TD>
<TD HEIGHT="8" COLSPAN="2"></TD></TR>
<TR STYLE="font-family:Times New Roman; font-size:10pt">
<TD VALIGN="top" NOWRAP>99.3</TD>
<TD VALIGN="bottom">&nbsp;&nbsp;</TD>
<TD VALIGN="top">2014 Equity Incentive Plan.</TD>
<TD VALIGN="bottom">&nbsp;&nbsp;</TD>
<TD VALIGN="top" NOWRAP ALIGN="center">S-1</TD>
<TD VALIGN="bottom">&nbsp;&nbsp;</TD>
<TD VALIGN="top" NOWRAP ALIGN="center">333-198355</TD>
<TD VALIGN="bottom">&nbsp;&nbsp;</TD>
<TD VALIGN="top" NOWRAP ALIGN="center">10.4</TD>
<TD VALIGN="bottom">&nbsp;&nbsp;</TD>
<TD VALIGN="top" NOWRAP ALIGN="center">September&nbsp;25,&nbsp;2014</TD></TR>
<TR STYLE="font-size:1pt">
<TD HEIGHT="8"></TD>
<TD HEIGHT="8" COLSPAN="2"></TD>
<TD HEIGHT="8" COLSPAN="2"></TD>
<TD HEIGHT="8" COLSPAN="2"></TD>
<TD HEIGHT="8" COLSPAN="2"></TD>
<TD HEIGHT="8" COLSPAN="2"></TD></TR>
<TR STYLE="font-family:Times New Roman; font-size:10pt">
<TD VALIGN="top" NOWRAP>99.4</TD>
<TD VALIGN="bottom">&nbsp;&nbsp;</TD>
<TD VALIGN="top">Forms of option agreement and option grant notice for 2014 Equity Incentive Plan.</TD>
<TD VALIGN="bottom">&nbsp;&nbsp;</TD>
<TD VALIGN="top" NOWRAP ALIGN="center">S-1</TD>
<TD VALIGN="bottom">&nbsp;&nbsp;</TD>
<TD VALIGN="top" NOWRAP ALIGN="center">333-198355</TD>
<TD VALIGN="bottom">&nbsp;&nbsp;</TD>
<TD VALIGN="top" NOWRAP ALIGN="center">10.5</TD>
<TD VALIGN="bottom">&nbsp;&nbsp;</TD>
<TD VALIGN="top" NOWRAP ALIGN="center">September 25, 2014</TD></TR>
<TR STYLE="font-size:1pt">
<TD HEIGHT="8"></TD>
<TD HEIGHT="8" COLSPAN="2"></TD>
<TD HEIGHT="8" COLSPAN="2"></TD>
<TD HEIGHT="8" COLSPAN="2"></TD>
<TD HEIGHT="8" COLSPAN="2"></TD>
<TD HEIGHT="8" COLSPAN="2"></TD></TR>
<TR STYLE="font-family:Times New Roman; font-size:10pt">
<TD VALIGN="top" NOWRAP>99.5</TD>
<TD VALIGN="bottom">&nbsp;&nbsp;</TD>
<TD VALIGN="top">2014 Employee Stock Purchase Plan.</TD>
<TD VALIGN="bottom">&nbsp;&nbsp;</TD>
<TD VALIGN="top" NOWRAP ALIGN="center">S-1</TD>
<TD VALIGN="bottom">&nbsp;&nbsp;</TD>
<TD VALIGN="top" NOWRAP ALIGN="center">333-198355</TD>
<TD VALIGN="bottom">&nbsp;&nbsp;</TD>
<TD VALIGN="top" NOWRAP ALIGN="center">10.6</TD>
<TD VALIGN="bottom">&nbsp;&nbsp;</TD>
<TD VALIGN="top" NOWRAP ALIGN="center">September 25, 2014</TD></TR>
</TABLE> <P STYLE="line-height:8.0pt;margin-top:0pt;margin-bottom:2pt;border-bottom:1px solid #000000;width:10%">&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="2%" VALIGN="top" ALIGN="left">*</TD>
<TD ALIGN="left" VALIGN="top">Filed herewith </TD></TR></TABLE>

<p Style='page-break-before:always'>
<HR  SIZE="3" style="COLOR:#999999" WIDTH="100%" ALIGN="CENTER">

 <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 Act of 1933, as amended, the Registrant certifies that it has reasonable grounds to believe
that it meets all of the requirements for filing on Form S-8 and has duly caused this Registration Statement to be signed on its behalf by the undersigned, thereunto duly authorized, in the city of South San Francisco, State of California, on
May&nbsp;11, 2015. </P> <P STYLE="font-size:12pt;margin-top:0pt;margin-bottom:0pt">&nbsp;</P><DIV ALIGN="right">
<TABLE CELLSPACING="0" CELLPADDING="0" WIDTH="40%" BORDER="0" STYLE="BORDER-COLLAPSE:COLLAPSE; font-family:Times New Roman; font-size:10pt">


<TR>
<TD WIDTH="6%"></TD>
<TD VALIGN="bottom" WIDTH="2%"></TD>
<TD WIDTH="92%"></TD></TR>


<TR STYLE="font-family:Times New Roman; font-size:10pt">
<TD VALIGN="top" COLSPAN="3"><B>C<SMALL>ALITHERA</SMALL> B<SMALL>IO</SMALL>S<SMALL>CIENCES</SMALL>, I<SMALL>NC</SMALL>.</B></TD></TR>
<TR STYLE="font-size:1pt">
<TD HEIGHT="16"></TD>
<TD HEIGHT="16" COLSPAN="2"></TD></TR>
<TR STYLE="font-family:Times New Roman; font-size:10pt">
<TD VALIGN="top">By:</TD>
<TD VALIGN="bottom">&nbsp;</TD>
<TD VALIGN="top"> <P STYLE="margin-top:0pt; margin-bottom:1pt; border-bottom:1px solid #000000; font-size:10pt; font-family:Times New Roman">&nbsp;/s/ Susan M. Molineaux</P></TD></TR>
<TR STYLE="font-family:Times New Roman; font-size:10pt">
<TD VALIGN="top"></TD>
<TD VALIGN="bottom">&nbsp;</TD>
<TD VALIGN="top">Susan M. Molineaux, Ph.D.</TD></TR>
<TR STYLE="font-family:Times New Roman; font-size:10pt">
<TD VALIGN="top"></TD>
<TD VALIGN="bottom">&nbsp;</TD>
<TD VALIGN="top">President and Chief Executive Officer</TD></TR>
</TABLE></DIV> <P STYLE="margin-top:24pt; margin-bottom:0pt; font-size:10pt; font-family:Times New Roman" ALIGN="center"><B>POWER OF ATTORNEY </B></P>
<P STYLE="margin-top:12pt; margin-bottom:0pt; text-indent:4%; font-size:10pt; font-family:Times New Roman"><B>K<SMALL>NOW</SMALL> A<SMALL>LL</SMALL> P<SMALL>ERSONS</SMALL> B<SMALL>Y</SMALL> T<SMALL>HESE</SMALL>
P<SMALL>RESENTS</SMALL></B><SMALL></SMALL>, that each person whose signature appears below constitutes and appoints Susan M. Molineaux, Ph.D. and William D. Waddill, and each or any one of them, his or her true and lawful attorney-in-fact and agent,
with full power of substitution and resubstitution, for him and in his name, place and stead, in any and all capacities, to sign any and all amendments (including post-effective amendments) to this Registration Statement, and to file the same, with
all exhibits thereto, and other documents in connection therewith, with the Securities and Exchange Commission, granting unto said attorneys-in-fact and agents, and each of them, full power and authority to do and perform each and every act and
thing requisite and necessary to be done in connection therewith, as fully to all intents and purposes as he or she might or could do in person, hereby ratifying and confirming all that said attorneys-in-fact and agents, or any of them, or their or
his or her substitutes or substitute, may lawfully do or cause to be done by virtue hereof. </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 Act of 1933, this Registration Statement has been signed by the following persons in the capacities and on the dates indicated. </P> <P STYLE="font-size:12pt;margin-top:0pt;margin-bottom:0pt">&nbsp;</P>
<TABLE CELLSPACING="0" CELLPADDING="0" WIDTH="100%" BORDER="0" STYLE="BORDER-COLLAPSE:COLLAPSE; font-family:Times New Roman; font-size:10pt">


<TR>
<TD WIDTH="37%"></TD>
<TD VALIGN="bottom" WIDTH="1%"></TD>
<TD WIDTH="44%"></TD>
<TD VALIGN="bottom" WIDTH="2%"></TD>
<TD WIDTH="15%"></TD></TR>
<TR STYLE="font-family:Times New Roman; font-size:8pt">
<TD VALIGN="bottom" NOWRAP ALIGN="center" STYLE="border-bottom:1.00pt solid #000000"> <P STYLE="margin-top:0pt; margin-bottom:1pt; font-size:8pt; font-family:Times New Roman" ALIGN="center"><B>Signature</B></P></TD>
<TD VALIGN="bottom">&nbsp;&nbsp;</TD>
<TD VALIGN="bottom" ALIGN="center" STYLE="border-bottom:1.00pt solid #000000"> <P STYLE="margin-top:0pt; margin-bottom:1pt; font-size:8pt; font-family:Times New Roman" ALIGN="center"><B>Title</B></P></TD>
<TD VALIGN="bottom">&nbsp;</TD>
<TD VALIGN="bottom" ALIGN="center" STYLE="border-bottom:1.00pt solid #000000"> <P STYLE="margin-top:0pt; margin-bottom:1pt; font-size:8pt; font-family:Times New Roman" ALIGN="center"><B>Date</B></P></TD></TR>


<TR STYLE="font-size:1pt">
<TD HEIGHT="16"></TD>
<TD HEIGHT="16" COLSPAN="2"></TD>
<TD HEIGHT="16" COLSPAN="2"></TD></TR>
<TR STYLE="font-family:Times New Roman; font-size:10pt">
<TD VALIGN="top"> <P STYLE="margin-top:0pt; margin-bottom:0pt; border-bottom:1px solid #000000; font-size:10pt; font-family:Times New Roman" ALIGN="center">/s/ Susan M. Molineaux</P>
<P STYLE="margin-top:0pt; margin-bottom:1pt; font-size:10pt; font-family:Times New Roman" ALIGN="center">Susan M. Molineaux, Ph.D.</P></TD>
<TD VALIGN="bottom">&nbsp;&nbsp;</TD>
<TD VALIGN="top"> <P STYLE="margin-top:0pt; margin-bottom:0pt; font-size:10pt; font-family:Times New Roman">President, Chief Executive Officer and Director</P>
<P STYLE="margin-top:0pt; margin-bottom:1pt; font-size:10pt; font-family:Times New Roman"><I>(Principal Executive Officer)</I></P></TD>
<TD VALIGN="bottom">&nbsp;</TD>
<TD VALIGN="top" ALIGN="center">May&nbsp;11,&nbsp;2015</TD></TR>
<TR STYLE="font-size:1pt">
<TD HEIGHT="16"></TD>
<TD HEIGHT="16" COLSPAN="2"></TD>
<TD HEIGHT="16" COLSPAN="2"></TD></TR>
<TR STYLE="font-family:Times New Roman; font-size:10pt">
<TD VALIGN="top"> <P STYLE="margin-top:0pt; margin-bottom:0pt; border-bottom:1px solid #000000; font-size:10pt; font-family:Times New Roman" ALIGN="center">/s/ William D. Waddill</P>
<P STYLE="margin-top:0pt; margin-bottom:1pt; font-size:10pt; font-family:Times New Roman" ALIGN="center">William D. Waddill</P></TD>
<TD VALIGN="bottom">&nbsp;&nbsp;</TD>
<TD VALIGN="top"> <P STYLE="margin-top:0pt; margin-bottom:0pt; font-size:10pt; font-family:Times New Roman">Senior Vice President, Chief Financial Officer, Treasurer and Secretary <I></I></P>
<P STYLE="margin-top:0pt; margin-bottom:1pt; font-size:10pt; font-family:Times New Roman"><I>(Principal Financial Accounting Officer)</I></P></TD>
<TD VALIGN="bottom">&nbsp;</TD>
<TD VALIGN="top" ALIGN="center">May 11, 2015</TD></TR>
<TR STYLE="font-size:1pt">
<TD HEIGHT="16"></TD>
<TD HEIGHT="16" COLSPAN="2"></TD>
<TD HEIGHT="16" COLSPAN="2"></TD></TR>
<TR STYLE="font-family:Times New Roman; font-size:10pt">
<TD VALIGN="top"> <P STYLE="margin-top:0pt; margin-bottom:0pt; border-bottom:1px solid #000000; font-size:10pt; font-family:Times New Roman" ALIGN="center">/s/ Ralph E. Christoffersen</P>
<P STYLE="margin-top:0pt; margin-bottom:1pt; font-size:10pt; font-family:Times New Roman" ALIGN="center">Ralph E. Christoffersen, Ph.D.</P></TD>
<TD VALIGN="bottom">&nbsp;&nbsp;</TD>
<TD VALIGN="top">Director</TD>
<TD VALIGN="bottom">&nbsp;</TD>
<TD VALIGN="top" ALIGN="center">May 11, 2015</TD></TR>
<TR STYLE="font-size:1pt">
<TD HEIGHT="16"></TD>
<TD HEIGHT="16" COLSPAN="2"></TD>
<TD HEIGHT="16" COLSPAN="2"></TD></TR>
<TR STYLE="font-family:Times New Roman; font-size:10pt">
<TD VALIGN="top"> <P STYLE="margin-top:0pt; margin-bottom:0pt; border-bottom:1px solid #000000; font-size:10pt; font-family:Times New Roman" ALIGN="center">/s/ Jonathan Drachman</P>
<P STYLE="margin-top:0pt; margin-bottom:1pt; font-size:10pt; font-family:Times New Roman" ALIGN="center">Jonathan Drachman, M.D.</P></TD>
<TD VALIGN="bottom">&nbsp;&nbsp;</TD>
<TD VALIGN="top">Director</TD>
<TD VALIGN="bottom">&nbsp;</TD>
<TD VALIGN="top" ALIGN="center">May 11, 2015</TD></TR>
<TR STYLE="font-size:1pt">
<TD HEIGHT="16"></TD>
<TD HEIGHT="16" COLSPAN="2"></TD>
<TD HEIGHT="16" COLSPAN="2"></TD></TR>
<TR STYLE="font-family:Times New Roman; font-size:10pt">
<TD VALIGN="top"> <P STYLE="margin-top:0pt; margin-bottom:0pt; border-bottom:1px solid #000000; font-size:10pt; font-family:Times New Roman" ALIGN="center">/s/ Jean M. George</P>
<P STYLE="margin-top:0pt; margin-bottom:1pt; font-size:10pt; font-family:Times New Roman" ALIGN="center">Jean M. George</P></TD>
<TD VALIGN="bottom">&nbsp;&nbsp;</TD>
<TD VALIGN="top">Director</TD>
<TD VALIGN="bottom">&nbsp;</TD>
<TD VALIGN="top" ALIGN="center">May 11, 2015</TD></TR>
<TR STYLE="font-size:1pt">
<TD HEIGHT="16"></TD>
<TD HEIGHT="16" COLSPAN="2"></TD>
<TD HEIGHT="16" COLSPAN="2"></TD></TR>
<TR STYLE="font-family:Times New Roman; font-size:10pt">
<TD VALIGN="top"> <P STYLE="margin-top:0pt; margin-bottom:0pt; border-bottom:1px solid #000000; font-size:10pt; font-family:Times New Roman" ALIGN="center">/s/ Deepa R. Pakianathan</P>
<P STYLE="margin-top:0pt; margin-bottom:1pt; font-size:10pt; font-family:Times New Roman" ALIGN="center">Deepa R. Pakianathan, Ph.D.</P></TD>
<TD VALIGN="bottom">&nbsp;&nbsp;</TD>
<TD VALIGN="top">Director</TD>
<TD VALIGN="bottom">&nbsp;</TD>
<TD VALIGN="top" ALIGN="center">May 11, 2015</TD></TR>
<TR STYLE="font-size:1pt">
<TD HEIGHT="16"></TD>
<TD HEIGHT="16" COLSPAN="2"></TD>
<TD HEIGHT="16" COLSPAN="2"></TD></TR>
<TR STYLE="font-family:Times New Roman; font-size:10pt">
<TD VALIGN="top"> <P STYLE="margin-top:0pt; margin-bottom:0pt; border-bottom:1px solid #000000; font-size:10pt; font-family:Times New Roman" ALIGN="center">/s/ H. Ward Wolff</P>
<P STYLE="margin-top:0pt; margin-bottom:1pt; font-size:10pt; font-family:Times New Roman" ALIGN="center">H. Ward Wolff</P></TD>
<TD VALIGN="bottom">&nbsp;&nbsp;</TD>
<TD VALIGN="top">Director</TD>
<TD VALIGN="bottom">&nbsp;</TD>
<TD VALIGN="top" ALIGN="center">May 11, 2015</TD></TR>
</TABLE>

<p Style='page-break-before:always'>
<HR  SIZE="3" style="COLOR:#999999" WIDTH="100%" ALIGN="CENTER">

 <P STYLE="margin-top:0pt; margin-bottom:0pt; font-size:10pt; font-family:Times New Roman" ALIGN="center"><B>EXHIBIT INDEX </B></P> <P STYLE="font-size:12pt;margin-top:0pt;margin-bottom:0pt">&nbsp;</P>
<TABLE CELLSPACING="0" CELLPADDING="0" WIDTH="100%" BORDER="0" STYLE="BORDER-COLLAPSE:COLLAPSE; font-family:Times New Roman; font-size:10pt" ALIGN="center">


<TR>
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<TD></TD>
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<TD></TD>
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<TD></TD></TR>
<TR STYLE="font-family:Times New Roman; font-size:8pt">
<TD VALIGN="bottom">&nbsp;</TD>
<TD VALIGN="bottom">&nbsp;&nbsp;</TD>
<TD VALIGN="bottom">&nbsp;</TD>
<TD VALIGN="bottom">&nbsp;&nbsp;</TD>
<TD VALIGN="bottom" COLSPAN="5" ALIGN="center" STYLE="border-bottom:1.00pt solid #000000"><B>Incorporated by Reference</B></TD>
<TD VALIGN="bottom">&nbsp;&nbsp;</TD>
<TD VALIGN="bottom">&nbsp;</TD></TR>
<TR STYLE="font-family:Times New Roman; font-size:8pt">
<TD VALIGN="bottom" 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" ALIGN="center" STYLE="border-bottom:1.00pt solid #000000"> <P STYLE="margin-top:0pt; margin-bottom:1pt; font-size:8pt; font-family:Times New Roman" ALIGN="center"><B>Description</B></P></TD>
<TD VALIGN="bottom">&nbsp;&nbsp;</TD>
<TD VALIGN="bottom" ALIGN="center" STYLE="border-bottom:1.00pt solid #000000"><B>Schedule</B><br><B>Form</B></TD>
<TD VALIGN="bottom">&nbsp;&nbsp;</TD>
<TD VALIGN="bottom" ALIGN="center" STYLE="border-bottom:1.00pt solid #000000"><B>File</B><br><B>Number</B></TD>
<TD VALIGN="bottom">&nbsp;&nbsp;</TD>
<TD VALIGN="bottom" ALIGN="center" STYLE="border-bottom:1.00pt solid #000000"><B>&nbsp;&nbsp;Exhibit&nbsp;&nbsp;</B></TD>
<TD VALIGN="bottom">&nbsp;&nbsp;</TD>
<TD VALIGN="bottom" ALIGN="center" STYLE="border-bottom:1.00pt solid #000000"><B>&nbsp;&nbsp;Filing&nbsp;Date&nbsp;&nbsp;</B></TD></TR>


<TR STYLE="font-size:1pt">
<TD HEIGHT="8"></TD>
<TD HEIGHT="8" COLSPAN="2"></TD>
<TD HEIGHT="8" COLSPAN="2"></TD>
<TD HEIGHT="8" COLSPAN="2"></TD>
<TD HEIGHT="8" COLSPAN="2"></TD>
<TD HEIGHT="8" COLSPAN="2"></TD></TR>
<TR STYLE="font-family:Times New Roman; font-size:10pt">
<TD VALIGN="top" NOWRAP>&nbsp;&nbsp;4.1</TD>
<TD VALIGN="bottom">&nbsp;&nbsp;</TD>
<TD VALIGN="top">Amended and Restated Certificate of Incorporation of Calithera Biosciences, Inc.</TD>
<TD VALIGN="bottom">&nbsp;&nbsp;</TD>
<TD VALIGN="top" NOWRAP ALIGN="center">8-K</TD>
<TD VALIGN="bottom">&nbsp;&nbsp;</TD>
<TD VALIGN="top" NOWRAP ALIGN="center">001-36644</TD>
<TD VALIGN="bottom">&nbsp;&nbsp;</TD>
<TD VALIGN="top" NOWRAP ALIGN="center">3.1</TD>
<TD VALIGN="bottom">&nbsp;&nbsp;</TD>
<TD VALIGN="top" NOWRAP ALIGN="center">October&nbsp;10,&nbsp;2014</TD></TR>
<TR STYLE="font-size:1pt">
<TD HEIGHT="8"></TD>
<TD HEIGHT="8" COLSPAN="2"></TD>
<TD HEIGHT="8" COLSPAN="2"></TD>
<TD HEIGHT="8" COLSPAN="2"></TD>
<TD HEIGHT="8" COLSPAN="2"></TD>
<TD HEIGHT="8" COLSPAN="2"></TD></TR>
<TR STYLE="font-family:Times New Roman; font-size:10pt">
<TD VALIGN="top" NOWRAP>&nbsp;&nbsp;4.2</TD>
<TD VALIGN="bottom">&nbsp;&nbsp;</TD>
<TD VALIGN="top">Amended and Restated Bylaws of Calithera Biosciences, Inc.</TD>
<TD VALIGN="bottom">&nbsp;&nbsp;</TD>
<TD VALIGN="top" NOWRAP ALIGN="center">S-1</TD>
<TD VALIGN="bottom">&nbsp;&nbsp;</TD>
<TD VALIGN="top" NOWRAP ALIGN="center">333-198-355</TD>
<TD VALIGN="bottom">&nbsp;&nbsp;</TD>
<TD VALIGN="top" NOWRAP ALIGN="center">3.4</TD>
<TD VALIGN="bottom">&nbsp;&nbsp;</TD>
<TD VALIGN="top" NOWRAP ALIGN="center">September&nbsp;19,&nbsp;2014</TD></TR>
<TR STYLE="font-size:1pt">
<TD HEIGHT="8"></TD>
<TD HEIGHT="8" COLSPAN="2"></TD>
<TD HEIGHT="8" COLSPAN="2"></TD>
<TD HEIGHT="8" COLSPAN="2"></TD>
<TD HEIGHT="8" COLSPAN="2"></TD>
<TD HEIGHT="8" COLSPAN="2"></TD></TR>
<TR STYLE="font-family:Times New Roman; font-size:10pt">
<TD VALIGN="top" NOWRAP>&nbsp;&nbsp;4.3</TD>
<TD VALIGN="bottom">&nbsp;&nbsp;</TD>
<TD VALIGN="top">Form of Common Stock Certificate.</TD>
<TD VALIGN="bottom">&nbsp;&nbsp;</TD>
<TD VALIGN="top" NOWRAP ALIGN="center">S-1</TD>
<TD VALIGN="bottom">&nbsp;&nbsp;</TD>
<TD VALIGN="top" NOWRAP ALIGN="center">333-198-355</TD>
<TD VALIGN="bottom">&nbsp;&nbsp;</TD>
<TD VALIGN="top" NOWRAP ALIGN="center">4.1</TD>
<TD VALIGN="bottom">&nbsp;&nbsp;</TD>
<TD VALIGN="top" NOWRAP ALIGN="center">September 25, 2014</TD></TR>
<TR STYLE="font-size:1pt">
<TD HEIGHT="8"></TD>
<TD HEIGHT="8" COLSPAN="2"></TD>
<TD HEIGHT="8" COLSPAN="2"></TD>
<TD HEIGHT="8" COLSPAN="2"></TD>
<TD HEIGHT="8" COLSPAN="2"></TD>
<TD HEIGHT="8" COLSPAN="2"></TD></TR>
<TR STYLE="font-family:Times New Roman; font-size:10pt">
<TD VALIGN="top" NOWRAP>&nbsp;&nbsp;5.1*</TD>
<TD VALIGN="bottom">&nbsp;&nbsp;</TD>
<TD VALIGN="top">Opinion of Cooley LLP.</TD>
<TD VALIGN="bottom">&nbsp;&nbsp;</TD>
<TD VALIGN="top"></TD>
<TD VALIGN="bottom">&nbsp;&nbsp;</TD>
<TD VALIGN="top"></TD>
<TD VALIGN="bottom">&nbsp;&nbsp;</TD>
<TD VALIGN="top"></TD>
<TD VALIGN="bottom">&nbsp;&nbsp;</TD>
<TD VALIGN="top"></TD></TR>
<TR STYLE="font-size:1pt">
<TD HEIGHT="8"></TD>
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<TD HEIGHT="8" COLSPAN="2"></TD>
<TD HEIGHT="8" COLSPAN="2"></TD>
<TD HEIGHT="8" COLSPAN="2"></TD>
<TD HEIGHT="8" COLSPAN="2"></TD></TR>
<TR STYLE="font-family:Times New Roman; font-size:10pt">
<TD VALIGN="top" NOWRAP>23.1*</TD>
<TD VALIGN="bottom">&nbsp;&nbsp;</TD>
<TD VALIGN="top">Consent of Independent Registered Public Accounting Firm.</TD>
<TD VALIGN="bottom">&nbsp;&nbsp;</TD>
<TD VALIGN="top"></TD>
<TD VALIGN="bottom">&nbsp;&nbsp;</TD>
<TD VALIGN="top"></TD>
<TD VALIGN="bottom">&nbsp;&nbsp;</TD>
<TD VALIGN="top"></TD>
<TD VALIGN="bottom">&nbsp;&nbsp;</TD>
<TD VALIGN="top"></TD></TR>
<TR STYLE="font-size:1pt">
<TD HEIGHT="8"></TD>
<TD HEIGHT="8" COLSPAN="2"></TD>
<TD HEIGHT="8" COLSPAN="2"></TD>
<TD HEIGHT="8" COLSPAN="2"></TD>
<TD HEIGHT="8" COLSPAN="2"></TD>
<TD HEIGHT="8" COLSPAN="2"></TD></TR>
<TR STYLE="font-family:Times New Roman; font-size:10pt">
<TD VALIGN="top" NOWRAP>23.2*</TD>
<TD VALIGN="bottom">&nbsp;&nbsp;</TD>
<TD VALIGN="top">Consent of Cooley LLP (included in Exhibit&nbsp;5.1).</TD>
<TD VALIGN="bottom">&nbsp;&nbsp;</TD>
<TD VALIGN="top"></TD>
<TD VALIGN="bottom">&nbsp;&nbsp;</TD>
<TD VALIGN="top"></TD>
<TD VALIGN="bottom">&nbsp;&nbsp;</TD>
<TD VALIGN="top"></TD>
<TD VALIGN="bottom">&nbsp;&nbsp;</TD>
<TD VALIGN="top"></TD></TR>
<TR STYLE="font-size:1pt">
<TD HEIGHT="8"></TD>
<TD HEIGHT="8" COLSPAN="2"></TD>
<TD HEIGHT="8" COLSPAN="2"></TD>
<TD HEIGHT="8" COLSPAN="2"></TD>
<TD HEIGHT="8" COLSPAN="2"></TD>
<TD HEIGHT="8" COLSPAN="2"></TD></TR>
<TR STYLE="font-family:Times New Roman; font-size:10pt">
<TD VALIGN="top" NOWRAP>24.1*</TD>
<TD VALIGN="bottom">&nbsp;&nbsp;</TD>
<TD VALIGN="top">Power of Attorney (see signature page hereto).</TD>
<TD VALIGN="bottom">&nbsp;&nbsp;</TD>
<TD VALIGN="top"></TD>
<TD VALIGN="bottom">&nbsp;&nbsp;</TD>
<TD VALIGN="top"></TD>
<TD VALIGN="bottom">&nbsp;&nbsp;</TD>
<TD VALIGN="top"></TD>
<TD VALIGN="bottom">&nbsp;&nbsp;</TD>
<TD VALIGN="top"></TD></TR>
<TR STYLE="font-size:1pt">
<TD HEIGHT="8"></TD>
<TD HEIGHT="8" COLSPAN="2"></TD>
<TD HEIGHT="8" COLSPAN="2"></TD>
<TD HEIGHT="8" COLSPAN="2"></TD>
<TD HEIGHT="8" COLSPAN="2"></TD>
<TD HEIGHT="8" COLSPAN="2"></TD></TR>
<TR STYLE="font-family:Times New Roman; font-size:10pt">
<TD VALIGN="top" NOWRAP>99.3</TD>
<TD VALIGN="bottom">&nbsp;&nbsp;</TD>
<TD VALIGN="top">2014 Equity Incentive Plan.</TD>
<TD VALIGN="bottom">&nbsp;&nbsp;</TD>
<TD VALIGN="top" NOWRAP ALIGN="center">S-1</TD>
<TD VALIGN="bottom">&nbsp;&nbsp;</TD>
<TD VALIGN="top" NOWRAP ALIGN="center">333-198355</TD>
<TD VALIGN="bottom">&nbsp;&nbsp;</TD>
<TD VALIGN="top" NOWRAP ALIGN="center">10.4</TD>
<TD VALIGN="bottom">&nbsp;&nbsp;</TD>
<TD VALIGN="top" NOWRAP ALIGN="center">September&nbsp;25,&nbsp;2014</TD></TR>
<TR STYLE="font-size:1pt">
<TD HEIGHT="8"></TD>
<TD HEIGHT="8" COLSPAN="2"></TD>
<TD HEIGHT="8" COLSPAN="2"></TD>
<TD HEIGHT="8" COLSPAN="2"></TD>
<TD HEIGHT="8" COLSPAN="2"></TD>
<TD HEIGHT="8" COLSPAN="2"></TD></TR>
<TR STYLE="font-family:Times New Roman; font-size:10pt">
<TD VALIGN="top" NOWRAP>99.4</TD>
<TD VALIGN="bottom">&nbsp;&nbsp;</TD>
<TD VALIGN="top">Forms of option agreement and option grant notice for 2014 Equity Incentive Plan.</TD>
<TD VALIGN="bottom">&nbsp;&nbsp;</TD>
<TD VALIGN="top" NOWRAP ALIGN="center">S-1</TD>
<TD VALIGN="bottom">&nbsp;&nbsp;</TD>
<TD VALIGN="top" NOWRAP ALIGN="center">333-198355</TD>
<TD VALIGN="bottom">&nbsp;&nbsp;</TD>
<TD VALIGN="top" NOWRAP ALIGN="center">10.5</TD>
<TD VALIGN="bottom">&nbsp;&nbsp;</TD>
<TD VALIGN="top" NOWRAP ALIGN="center">September 25, 2014</TD></TR>
<TR STYLE="font-size:1pt">
<TD HEIGHT="8"></TD>
<TD HEIGHT="8" COLSPAN="2"></TD>
<TD HEIGHT="8" COLSPAN="2"></TD>
<TD HEIGHT="8" COLSPAN="2"></TD>
<TD HEIGHT="8" COLSPAN="2"></TD>
<TD HEIGHT="8" COLSPAN="2"></TD></TR>
<TR STYLE="font-family:Times New Roman; font-size:10pt">
<TD VALIGN="top" NOWRAP>99.5</TD>
<TD VALIGN="bottom">&nbsp;&nbsp;</TD>
<TD VALIGN="top">2014 Employee Stock Purchase Plan.</TD>
<TD VALIGN="bottom">&nbsp;&nbsp;</TD>
<TD VALIGN="top" NOWRAP ALIGN="center">S-1</TD>
<TD VALIGN="bottom">&nbsp;&nbsp;</TD>
<TD VALIGN="top" NOWRAP ALIGN="center">333-198355</TD>
<TD VALIGN="bottom">&nbsp;&nbsp;</TD>
<TD VALIGN="top" NOWRAP ALIGN="center">10.6</TD>
<TD VALIGN="bottom">&nbsp;&nbsp;</TD>
<TD VALIGN="top" NOWRAP ALIGN="center">September 25, 2014</TD></TR>
</TABLE> <P STYLE="line-height:8.0pt;margin-top:0pt;margin-bottom:2pt;border-bottom:1px solid #000000;width:10%">&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="2%" VALIGN="top" ALIGN="left">*</TD>
<TD ALIGN="left" VALIGN="top">Filed herewith. </TD></TR></TABLE>
</BODY></HTML>
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S-8
As filed with the U.S. Securities and Exchange Commission on May 11, 2015
Registration No. 333-
UNITED STATES
SECURITIES AND EXCHANGE COMMISSION
Washington, D.C. 20549
FORM S-8
REGISTRATION STATEMENT
UNDER
THE
SECURITIES ACT OF 1933
Calithera Biosciences, Inc.
(Exact name of registrant as specified in its charter)
Delaware
27-2366329
(State or other jurisdiction of
Incorporation or organization)
(I.R.S. Employer
Identification No.)
343 Oyster Point Blvd., Suite 200
South San Francisco, California 94080
(Address of principal executive offices) (Zip code)
Calithera Biosciences, Inc. 2014 Equity Incentive Plan
Calithera Biosciences, Inc. 2014 Employee Stock Purchase Plan
(Full title of the plans)
Susan M.
Molineaux, Ph.D.
President and Chief Executive Officer
343 Oyster Point Blvd., Suite 200
South San Francisco, California 94080
(650) 870-1000
(Name and
address of agent for service) (Telephone number, including area code, of agent for service)
Copies to:
Barbara A. Kosacz
John T. McKenna
Danielle
E. Naftulin
Cooley LLP
3175 Hanover Street
Palo
Alto, California 94304
(650) 843-5000
Indicate by check mark whether
the registrant is a large accelerated filer, an accelerated filer, a non-accelerated filer, or a smaller reporting company. See the definitions of "large accelerated filer," "accelerated filer" and "smaller reporting
company" in Rule 12b-2 of the Exchange Act.
Large accelerated filer
¨
Accelerated filer
¨
Non-accelerated filer
x
(Do not check if a smaller reporting company)
Smaller reporting company
¨
CALCULATION OF REGISTRATION FEE
Title of Securities
to be Registered
Amount
to be
Registered(1)
Proposed
Maximum
Offering Price
per Share(2)
Proposed
Maximum
Aggregate
Offering Price(2)
Amount of
Registration Fee
Common Stock, par value $0.0001 per share
– 2014 Equity Incentive Plan
717,735
$9.275
$6,656,992.13
$773.55
– 2014 Employee Stock Purchase Plan
179,433
$9.275
$1,664,241.08
$193.39
Total
897,168
$8,321,233.21
$966.94
(1)
Pursuant to Rule 416(a) under the Securities Act of 1933, as amended, this Registration Statement shall also cover any additional shares of common stock of Calithera Biosciences, Inc. that become issuable under the 2014
Equity Incentive Plan, and the 2014 Employee Stock Purchase Plan set forth herein by reason of any stock dividend, stock split, recapitalization, or other similar transaction effected that results in an increase to the number of outstanding shares
of the Registrant's common stock.
(2)
Estimated in accordance with Rule 457(c) and (h) under the Securities Act solely for the purpose of calculating the registration fee on the basis of $9.275, the average of the high and low prices of the
Registrant's common stock as reported on The NASDAQ Global Market on May 6, 2015.
EXPLANATORY NOTE
Calithera Biosciences, Inc. (the "
Registrant
") is filing this Registration Statement on Form S-8 for the purpose
of registering an additional (a) 717,735 shares of its common stock, par value $0.0001 per share (the "
Common Stock
"), issuable to eligible persons under the 2014 Equity Incentive Plan, which Common Stock is in addition
to the shares of Common Stock registered on the Registrant's Form S-8 filed on October 2, 2014 (File No. 333-199126) and (the "
Prior Form S-8
") and (b) 179,433 shares of Common Stock issuable to
eligible persons under the 2014 Employee Stock Purchase Plan, which Common Stock is in addition to the shares of Common Stock registered on the Prior Form S-8.
PART II
ITEM 3.
INCORPORATION OF CERTAIN DOCUMENTS BY REFERENCE
Pursuant to General Instruction E to
Form S-8, the contents of the Prior Form S-8 are incorporated by reference herein.
All other reports and documents subsequently filed by
the Registrant pursuant to Sections 13(a), 13(c), 14 and 15(d) of the Exchange Act (other than Current Reports furnished under Item 2.02 or Item 7.01 of Form 8-K and exhibits furnished on such form that relate to such items) on or after
the date of this Registration Statement and prior to the filing of a post-effective amendment to this Registration Statement which indicates that all securities offered have been sold or which deregisters all securities then remaining unsold, shall
be deemed to be incorporated by reference herein and to be a part of this Registration Statement from the date of the filing of such reports and documents. Any statement contained in a document incorporated or deemed to be incorporated by reference
herein shall be deemed to be modified or superseded for purposes of this Registration Statement to the extent that a statement contained herein or in any subsequently filed document that also is deemed to be incorporated by reference herein modifies
or supersedes such statement. Any such statement so modified or superseded shall not be deemed, except as so modified or superseded, to constitute a part of this Registration Statement.
ITEM 8.
EXHIBITS
Incorporated by Reference
Exhibit
Number
Description
Schedule
Form
File
Number
Exhibit
Filing Date
4.1
Amended and Restated Certificate of Incorporation of Calithera Biosciences, Inc.
8-K
001-36644
3.1
October 10, 2014
4.2
Amended and Restated Bylaws of Calithera Biosciences, Inc.
S-1
333-198-355
3.4
September 19, 2014
4.3
Form of Common Stock Certificate.
S-1
333-198-355
4.1
September 25, 2014
5.1*
Opinion of Cooley LLP.
23.1*
Consent of Independent Registered Public Accounting Firm.
23.2*
Consent of Cooley LLP (included in Exhibit 5.1).
24.1*
Power of Attorney (see signature page hereto).
99.3
2014 Equity Incentive Plan.
S-1
333-198355
10.4
September 25, 2014
99.4
Forms of option agreement and option grant notice for 2014 Equity Incentive Plan.
S-1
333-198355
10.5
September 25, 2014
99.5
2014 Employee Stock Purchase Plan.
S-1
333-198355
10.6
September 25, 2014
*
Filed herewith
SIGNATURES
Pursuant to the requirements of the Securities Act of 1933, as amended, the Registrant certifies that it has reasonable grounds to believe
that it meets all of the requirements for filing on Form S-8 and has duly caused this Registration Statement to be signed on its behalf by the undersigned, thereunto duly authorized, in the city of South San Francisco, State of California, on
May 11, 2015.
C
ALITHERA
B
IO
S
CIENCES
, I
NC
.
By:
/s/ Susan M. Molineaux
Susan M. Molineaux, Ph.D.
President and Chief Executive Officer
POWER OF ATTORNEY
K
NOW
A
LL
P
ERSONS
B
Y
T
HESE
P
RESENTS
, that each person whose signature appears below constitutes and appoints Susan M. Molineaux, Ph.D. and William D. Waddill, and each or any one of them, his or her true and lawful attorney-in-fact and agent,
with full power of substitution and resubstitution, for him and in his name, place and stead, in any and all capacities, to sign any and all amendments (including post-effective amendments) to this Registration Statement, and to file the same, with
all exhibits thereto, and other documents in connection therewith, with the Securities and Exchange Commission, granting unto said attorneys-in-fact and agents, and each of them, full power and authority to do and perform each and every act and
thing requisite and necessary to be done in connection therewith, as fully to all intents and purposes as he or she might or could do in person, hereby ratifying and confirming all that said attorneys-in-fact and agents, or any of them, or their or
his or her substitutes or substitute, may lawfully do or cause to be done by virtue hereof.
Pursuant to the requirements of the
Securities Act of 1933, this Registration Statement has been signed by the following persons in the capacities and on the dates indicated.
Signature
Title
Date
/s/ Susan M. Molineaux
Susan M. Molineaux, Ph.D.
President, Chief Executive Officer and Director
(Principal Executive Officer)
May 11, 2015
/s/ William D. Waddill
William D. Waddill
Senior Vice President, Chief Financial Officer, Treasurer and Secretary
(Principal Financial Accounting Officer)
May 11, 2015
/s/ Ralph E. Christoffersen
Ralph E. Christoffersen, Ph.D.
Director
May 11, 2015
/s/ Jonathan Drachman
Jonathan Drachman, M.D.
Director
May 11, 2015
/s/ Jean M. George
Jean M. George
Director
May 11, 2015
/s/ Deepa R. Pakianathan
Deepa R. Pakianathan, Ph.D.
Director
May 11, 2015
/s/ H. Ward Wolff
H. Ward Wolff
Director
May 11, 2015
EXHIBIT INDEX
Incorporated by Reference
Exhibit
Number
Description
Schedule
Form
File
Number
Exhibit
Filing Date
4.1
Amended and Restated Certificate of Incorporation of Calithera Biosciences, Inc.
8-K
001-36644
3.1
October 10, 2014
4.2
Amended and Restated Bylaws of Calithera Biosciences, Inc.
S-1
333-198-355
3.4
September 19, 2014
4.3
Form of Common Stock Certificate.
S-1
333-198-355
4.1
September 25, 2014
5.1*
Opinion of Cooley LLP.
23.1*
Consent of Independent Registered Public Accounting Firm.
23.2*
Consent of Cooley LLP (included in Exhibit 5.1).
24.1*
Power of Attorney (see signature page hereto).
99.3
2014 Equity Incentive Plan.
S-1
333-198355
10.4
September 25, 2014
99.4
Forms of option agreement and option grant notice for 2014 Equity Incentive Plan.
S-1
333-198355
10.5
September 25, 2014
99.5
2014 Employee Stock Purchase Plan.
S-1
333-198355
10.6
September 25, 2014
*
Filed herewith.