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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 Securities and Exchange Commission on February&nbsp;27, 2024 </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-&#8195;&#8195;&#8195;&#8195; </B></P> <P STYLE="font-size:4pt;margin-top:0pt;margin-bottom:0pt">&nbsp;</P>
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<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: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 <FONT
STYLE="white-space:nowrap">S-8</FONT> </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: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:24pt; font-family:Times New Roman" ALIGN="center"><B>Syndax Pharmaceuticals, 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: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:6pt;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><FONT STYLE="white-space:nowrap">32-0162505</FONT></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>(IRS employer</B></P>
<P STYLE="margin-top:0pt; margin-bottom:1pt; font-size:8pt; font-family:Times New Roman" ALIGN="center"><B>identification number)</B></P></TD></TR>
</TABLE> <P STYLE="margin-top:6pt; margin-bottom:0pt; font-size:10pt; font-family:Times New Roman" ALIGN="center"><B>35 Gatehouse Drive </B></P>
<P STYLE="margin-top:0pt; margin-bottom:0pt; font-size:10pt; font-family:Times New Roman" ALIGN="center"><B>Building D, Floor 3 </B></P>
<P STYLE="margin-top:0pt; margin-bottom:0pt; font-size:10pt; font-family:Times New Roman" ALIGN="center"><B>Waltham, Massachusetts 02451 </B></P>
<P STYLE="margin-top:0pt; margin-bottom:0pt; font-size:10pt; font-family:Times New Roman" ALIGN="center"><B>(781) <FONT STYLE="white-space:nowrap">419-1400</FONT> </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) </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:10pt; font-family:Times New Roman" ALIGN="center"><B>2015 Omnibus
Incentive Plan </B></P> <P STYLE="margin-top:0pt; margin-bottom:0pt; font-size:10pt; font-family:Times New Roman" ALIGN="center"><B>2015 Employee Stock Purchase Plan </B></P>
<P STYLE="margin-top:0pt; margin-bottom:0pt; font-size:10pt; font-family:Times New Roman" ALIGN="center"><B>2023 Inducement Plan </B></P>
<P STYLE="margin-top:0pt; margin-bottom:0pt; font-size:10pt; font-family:Times New Roman" ALIGN="center"><B>Inducement Stock Options </B></P>
<P STYLE="margin-top:0pt; margin-bottom:0pt; font-size:8pt; font-family:Times New Roman" ALIGN="center"><B>(Full titles of the plans) </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:10pt; font-family:Times New Roman" ALIGN="center"><B>Michael A.
Metzger </B></P> <P STYLE="margin-top:0pt; margin-bottom:0pt; font-size:10pt; font-family:Times New Roman" ALIGN="center"><B>Chief Executive Officer </B></P>
<P STYLE="margin-top:0pt; margin-bottom:0pt; font-size:10pt; font-family:Times New Roman" ALIGN="center"><B>Syndax Pharmaceuticals, Inc. </B></P>
<P STYLE="margin-top:0pt; margin-bottom:0pt; font-size:10pt; font-family:Times New Roman" ALIGN="center"><B>35 Gatehouse Drive </B></P>
<P STYLE="margin-top:0pt; margin-bottom:0pt; font-size:10pt; font-family:Times New Roman" ALIGN="center"><B>Building D, Floor 3 </B></P>
<P STYLE="margin-top:0pt; margin-bottom:0pt; font-size:10pt; font-family:Times New Roman" ALIGN="center"><B>Waltham, Massachusetts 02451 </B></P>
<P STYLE="margin-top:0pt; margin-bottom:0pt; font-size:10pt; font-family:Times New Roman" ALIGN="center"><B>(781) <FONT STYLE="white-space:nowrap">419-1400</FONT> </B></P>
<P STYLE="margin-top:0pt; margin-bottom:0pt; font-size:8pt; font-family:Times New Roman" ALIGN="center"><B>(Name, address and telephone number of agent for service) </B></P> <P STYLE="font-size:6pt;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>Laura A. Berezin</B></P>
<P STYLE="margin-top:0pt; margin-bottom:0pt; font-size:10pt; font-family:Times New Roman" ALIGN="center"><B>Jaime L. Chase</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>1700 Seventh Avenue, Suite 1900</B></P>
<P STYLE="margin-top:0pt; margin-bottom:0pt; font-size:10pt; font-family:Times New Roman" ALIGN="center"><B>Seattle, Washington 98101</B></P>
<P STYLE="margin-top:0pt; margin-bottom:1pt; font-size:10pt; font-family:Times New Roman" ALIGN="center"><B>(206) <FONT STYLE="white-space:nowrap">452-8700</FONT></B></P></TD>
<TD VALIGN="bottom">&nbsp;</TD>
<TD VALIGN="top" ALIGN="center"> <P STYLE="margin-top:0pt; margin-bottom:0pt; font-size:10pt; font-family:Times New Roman" ALIGN="center"><B>Luke J. Albrecht</B></P>
<P STYLE="margin-top:0pt; margin-bottom:0pt; font-size:10pt; font-family:Times New Roman" ALIGN="center"><B>General Counsel&nbsp;&amp; Secretary</B></P>
<P STYLE="margin-top:0pt; margin-bottom:0pt; font-size:10pt; font-family:Times New Roman" ALIGN="center"><B>Syndax Pharmaceuticals, Inc.</B></P>
<P STYLE="margin-top:0pt; margin-bottom:0pt; font-size:10pt; font-family:Times New Roman" ALIGN="center"><B>Building D, Floor 3</B></P> <P STYLE="margin-top:0pt; margin-bottom:0pt; font-size:10pt; font-family:Times New Roman" ALIGN="center"><B>35
Gatehouse Drive</B></P> <P STYLE="margin-top:0pt; margin-bottom:0pt; font-size:10pt; font-family:Times New Roman" ALIGN="center"><B>Waltham, Massachusetts 02451</B></P>
<P STYLE="margin-top:0pt; margin-bottom:1pt; font-size:10pt; font-family:Times New Roman" ALIGN="center"><B>(781) <FONT STYLE="white-space:nowrap">419-1400</FONT></B></P></TD></TR>
</TABLE> <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; text-indent:4%; font-size:10pt; font-family:Times New Roman">Indicate by check mark whether the registrant is a large accelerated filer, an accelerated filer, a
<FONT STYLE="white-space:nowrap">non-accelerated</FONT> filer, a smaller reporting company, or an emerging growth company. See the definitions of &#147;large accelerated filer,&#148; &#147;accelerated filer,&#148; &#147;smaller reporting
company,&#148; and &#147;emerging growth company&#148; in Rule <FONT STYLE="white-space:nowrap">12b-2</FONT> of the Exchange Act. </P> <P STYLE="font-size:8pt;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">&#9746;</TD>
<TD VALIGN="bottom">&nbsp;&nbsp;</TD>
<TD VALIGN="bottom">Accelerated filer</TD>
<TD VALIGN="bottom">&nbsp;</TD>
<TD VALIGN="bottom">&#9744;</TD></TR>
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<TD HEIGHT="8" COLSPAN="2"></TD>
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<TD VALIGN="bottom"><FONT STYLE="white-space:nowrap">Non-accelerated</FONT> filer</TD>
<TD VALIGN="bottom">&nbsp;</TD>
<TD VALIGN="bottom">&#9744;</TD>
<TD VALIGN="bottom">&nbsp;&nbsp;</TD>
<TD VALIGN="bottom">Smaller&nbsp;reporting&nbsp;company</TD>
<TD VALIGN="bottom">&nbsp;</TD>
<TD VALIGN="bottom">&#9744;</TD></TR>
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<TD HEIGHT="8"></TD>
<TD HEIGHT="8" COLSPAN="2"></TD>
<TD HEIGHT="8" COLSPAN="2"></TD>
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<TD VALIGN="bottom"></TD>
<TD VALIGN="bottom">&nbsp;</TD>
<TD VALIGN="bottom"></TD>
<TD VALIGN="bottom">&nbsp;&nbsp;</TD>
<TD VALIGN="bottom">Emerging growth company</TD>
<TD VALIGN="bottom">&nbsp;</TD>
<TD VALIGN="bottom">&#9744;</TD></TR>
</TABLE> <P STYLE="margin-top:6pt; margin-bottom:0pt; text-indent:4%; font-size:10pt; font-family:Times New Roman">If an emerging growth company, indicate by check mark if the registrant has elected not to use the extended
transition period for complying with any new or revised financial accounting standards provided pursuant to Section&nbsp;7(a)(2)(B) of the Securities Act.&#8194;&#9744; </P> <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; font-size:10pt; font-family:Times New Roman">This Registration Statement on Form <FONT STYLE="white-space:nowrap">S-8</FONT> (&#147;Registration Statement&#148;) is being filed for the purpose of
registering (i) 3,393,065 shares of the Registrant&#146;s common stock, par value $0.0001 per share (&#147;Common Stock&#148;), reserved and available for issuance under the Registrant&#146;s 2015 Omnibus Incentive Plan, (ii) 250,000 shares of the
Registrant&#146;s Common Stock, reserved and available for issuance under the Registrant&#146;s 2015 Employee Stock Purchase Plan, (iii) 1,075,750 shares of the Registrant&#146;s Common Stock, reserved and available for issuance under the
Registrant&#146;s 2023 Inducement Plan (the &#147;Inducement Plan&#148;), and (iv) 24,250 shares of common stock issuable upon the exercise of outstanding options granted to new employees as inducement awards in connection with the commencement of
employment pursuant to Nasdaq Listing Rule 5635(c)(4) pursuant to the Inducement Plan. </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="margin-top:6pt; margin-bottom:0pt; font-size:10pt; font-family:Times New Roman" ALIGN="center"><B>INFORMATION REQUIRED IN THE REGISTRATION STATEMENT </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&#8201;3.</B></TD>
<TD ALIGN="left" VALIGN="top"> <P STYLE=" margin-top:0pt ; margin-bottom:0pt; font-size:10pt; font-family:Times New Roman; " ALIGN="left"><B>Incorporation of Documents by References </B></P></TD></TR></TABLE>
<P STYLE="margin-top:6pt; margin-bottom:0pt; font-size:10pt; font-family:Times New Roman">The Registrant previously registered shares of its Common Stock for issuance under the 2015 Plan and the ESPP under Registration Statements on Form <FONT
STYLE="white-space:nowrap">S-8</FONT> filed with the Securities and Exchange Commission on <A HREF="http://www.sec.gov/Archives/edgar/data/1395937/000119312516518181/d166957ds8.htm">March&nbsp;25, 2016</A> (File
<FONT STYLE="white-space:nowrap">No.&nbsp;333-210412),</FONT> <A HREF="http://www.sec.gov/Archives/edgar/data/1395937/000119312517268644/d430439ds8.htm">August&nbsp;25, 2017</A> (File <FONT STYLE="white-space:nowrap">No.&nbsp;
333-220172),</FONT> <A HREF="http://www.sec.gov/Archives/edgar/data/1395937/000156459018020504/sndx-s8.htm">August&nbsp;8, 2018</A> (File <FONT STYLE="white-space:nowrap">No.&nbsp;
333-226678),</FONT> <A HREF="http://www.sec.gov/Archives/edgar/data/1395937/000156459019030084/sndx-s8.htm">August&nbsp;7, 2019</A> (File <FONT STYLE="white-space:nowrap">No.&nbsp;
333-233083),</FONT> <A HREF="http://www.sec.gov/Archives/edgar/data/1395937/000156459020037767/sndx-s8.htm">August&nbsp;6, 2020</A> (File <FONT STYLE="white-space:nowrap">No.&nbsp;
333-241654),</FONT> <A HREF="http://www.sec.gov/Archives/edgar/data/1395937/000156459021042630/sndx-s8.htm">August&nbsp;9, 2021</A> (File <FONT STYLE="white-space:nowrap">No.&nbsp;
333-258628),</FONT> <A HREF="http://www.sec.gov/Archives/edgar/data/1395937/000156459022008120/sndx-s8.htm">March&nbsp;1, 2022</A> (File <FONT STYLE="white-space:nowrap">No.&nbsp;
333-263185)</FONT> and <A HREF="http://www.sec.gov/Archives/edgar/data/1395937/000095017023005102/sndx-20223-02-s8.htm">February<U></U>&nbsp;28, 2023</A> (File <FONT STYLE="white-space:nowrap">No.&nbsp;333-270093).</FONT> Pursuant to General
Instruction E to Form <FONT STYLE="white-space:nowrap">S-8,</FONT> this Registration Statement hereby incorporates by reference the contents of the Registration Statements referenced above. </P>
<P STYLE="font-size:18pt;margin-top:0pt;margin-bottom:0pt">&nbsp;</P>
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<TD WIDTH="10%" VALIGN="top" ALIGN="left"><B>Item&#8201;8.</B></TD>
<TD ALIGN="left" VALIGN="top"> <P STYLE=" margin-top:0pt ; margin-bottom:0pt; font-size:10pt; font-family:Times New Roman; " ALIGN="left"><B>Exhibits </B></P></TD></TR></TABLE>
<P STYLE="margin-top:6pt; margin-bottom:0pt; font-size:10pt; font-family:Times New Roman">The exhibits to this Registration Statement are listed below and incorporated by reference herein. </P>
<P STYLE="font-size:12pt;margin-top:0pt;margin-bottom:0pt">&nbsp;</P>
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<TD VALIGN="bottom" NOWRAP ALIGN="center" STYLE="border-bottom:1.00pt solid #000000"><B>Exhibit<BR>Number</B></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>Exhibit Description</B></P></TD></TR>


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<TD VALIGN="top" NOWRAP>&#8199;&#8199;4.1</TD>
<TD VALIGN="bottom">&nbsp;&nbsp;</TD>
<TD VALIGN="top"><A HREF="http://www.sec.gov/Archives/edgar/data/0001395937/000119312516496764/d119516dex31.htm">Amended and Restated Certificate of Incorporation (incorporated herein by reference to Exhibit 3.1 to the Registrant&#146;s Current Report
 on Form <FONT STYLE="white-space:nowrap">8-K,</FONT> SEC File <FONT STYLE="white-space:nowrap">No.&nbsp;001-37708,</FONT> filed with the SEC on March&nbsp;8, 2016).</A></TD></TR>
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<TD VALIGN="top" NOWRAP>&#8199;&#8199;4.2</TD>
<TD VALIGN="bottom">&nbsp;&nbsp;</TD>
<TD VALIGN="top"><A HREF="http://www.sec.gov/Archives/edgar/data/1395937/000095017023022802/sndx-ex3_1.htm">Certificate of Amendment to the Amended and Restated Certificate of Incorporation of the Company (incorporated herein by reference to Exhibit 3.1
to the Company&#146;s Current Report on Form <FONT STYLE="white-space:nowrap">8-K</FONT> (File No.<U></U><FONT STYLE="white-space:nowrap">&nbsp;001-37708),</FONT> as filed with the SEC on May<U></U>&nbsp;18, 2023).</A></TD></TR>
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<TD VALIGN="top" NOWRAP>&#8199;&#8199;4.3</TD>
<TD VALIGN="bottom">&nbsp;&nbsp;</TD>
<TD VALIGN="top"><A HREF="http://www.sec.gov/Archives/edgar/data/0001395937/000119312516496764/d119516dex32.htm">Amended and Restated Bylaws (incorporated herein by reference to Exhibit 3.2 to the Registrant&#146;s Current Report on Form <FONT
STYLE="white-space:nowrap">8-K,</FONT> SEC File <FONT STYLE="white-space:nowrap">No.&nbsp;001-37708,</FONT> filed with the SEC on March&nbsp;8, 2016).</A></TD></TR>
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<TD VALIGN="top" NOWRAP>&#8199;&#8199;5.1</TD>
<TD VALIGN="bottom">&nbsp;&nbsp;</TD>
<TD VALIGN="top"><A HREF="d769709dex51.htm">Opinion of Cooley LLP. </A></TD></TR>
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<TR STYLE="page-break-inside:avoid ; font-family:Times New Roman; font-size:10pt">
<TD VALIGN="top" NOWRAP>&#8199;23.1</TD>
<TD VALIGN="bottom">&nbsp;&nbsp;</TD>
<TD VALIGN="top"><A HREF="d769709dex231.htm">Consent of Independent Registered Accounting Firm. </A></TD></TR>
<TR STYLE="font-size:1pt">
<TD HEIGHT="8"></TD>
<TD HEIGHT="8" COLSPAN="2"></TD></TR>
<TR STYLE="page-break-inside:avoid ; font-family:Times New Roman; font-size:10pt">
<TD VALIGN="top" NOWRAP>&#8199;23.2</TD>
<TD VALIGN="bottom">&nbsp;&nbsp;</TD>
<TD VALIGN="top"><A HREF="d769709dex51.htm">Consent of Cooley LLP (included in Exhibit 5.1). </A></TD></TR>
<TR STYLE="font-size:1pt">
<TD HEIGHT="8"></TD>
<TD HEIGHT="8" COLSPAN="2"></TD></TR>
<TR STYLE="page-break-inside:avoid ; font-family:Times New Roman; font-size:10pt">
<TD VALIGN="top" NOWRAP>&#8199;24.1</TD>
<TD VALIGN="bottom">&nbsp;&nbsp;</TD>
<TD VALIGN="top"><A HREF="d769709ds8.htm#sig">Power of Attorney (included on the signature page to this Registration Statement). </A></TD></TR>
<TR STYLE="font-size:1pt">
<TD HEIGHT="8"></TD>
<TD HEIGHT="8" COLSPAN="2"></TD></TR>
<TR STYLE="page-break-inside:avoid ; font-family:Times New Roman; font-size:10pt">
<TD VALIGN="top" NOWRAP>&#8199;99.1</TD>
<TD VALIGN="bottom">&nbsp;&nbsp;</TD>
<TD VALIGN="top"><A HREF="http://www.sec.gov/Archives/edgar/data/0001395937/000119312516518181/d166957dex413.htm">2015 Omnibus Incentive Plan (incorporated herein by reference to Exhibit 4.13 to the Company&#146;s Registration Statement on Form <FONT
STYLE="white-space:nowrap">S-8,</FONT> SEC File <FONT STYLE="white-space:nowrap">No.&nbsp;333-210412,</FONT> as filed with the SEC on March&nbsp;25, 2016).</A></TD></TR>
<TR STYLE="font-size:1pt">
<TD HEIGHT="8"></TD>
<TD HEIGHT="8" COLSPAN="2"></TD></TR>
<TR STYLE="page-break-inside:avoid ; font-family:Times New Roman; font-size:10pt">
<TD VALIGN="top" NOWRAP>&#8199;99.2</TD>
<TD VALIGN="bottom">&nbsp;&nbsp;</TD>
<TD VALIGN="top"><A HREF="http://www.sec.gov/Archives/edgar/data/1395937/000119312516420122/d39288dex1013.htm">Form of Incentive Stock Option Agreement under 2015 Omnibus Incentive Plan (incorporated herein by reference to Exhibit 10.13 to the Registrant&#146;s
 Registration Statement on Form <FONT STYLE="white-space:nowrap">S-1,</FONT> SEC File <FONT STYLE="white-space:nowrap">No.&nbsp;333-208861,</FONT> filed with the SEC on January&nbsp;4, 2016).</A></TD></TR>
</TABLE>
</DIV></Center>


<p style="margin-top:1em; margin-bottom:0em; page-break-before:always"> </p>
<HR SIZE="3" style="COLOR:#999999" WIDTH="100%" ALIGN="CENTER">


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<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 WIDTH="6%"></TD>

<TD VALIGN="bottom" WIDTH="4%"></TD>
<TD WIDTH="92%"></TD></TR>


<TR STYLE="page-break-inside:avoid ; font-family:Times New Roman; font-size:10pt">
<TD VALIGN="top" NOWRAP> <P STYLE=" margin-top:0pt ; margin-bottom:0pt; margin-left:1.00em; text-indent:-1.00em; font-size:10pt; font-family:Times New Roman">&#8199;99.3</P></TD>
<TD VALIGN="bottom">&nbsp;&nbsp;</TD>
<TD VALIGN="top"><A HREF="http://www.sec.gov/Archives/edgar/data/0001395937/000119312516420122/d39288dex1014.htm">Form of <FONT STYLE="white-space:nowrap">Non-Qualified</FONT> Option Agreement under 2015 Omnibus Incentive Plan (incorporated herein by reference
 to Exhibit 10.14 to the Registrant&#146;s Registration Statement on Form <FONT STYLE="white-space:nowrap">S-1,</FONT> SEC File <FONT STYLE="white-space:nowrap">No.&nbsp;333-208861,</FONT> filed with the SEC on January&nbsp;4, 2016).</A></TD></TR>
<TR STYLE="font-size:1pt">
<TD HEIGHT="8"></TD>
<TD HEIGHT="8" COLSPAN="2"></TD></TR>
<TR STYLE="page-break-inside:avoid ; font-family:Times New Roman; font-size:10pt">
<TD VALIGN="top" NOWRAP> <P STYLE=" margin-top:0pt ; margin-bottom:0pt; margin-left:1.00em; text-indent:-1.00em; font-size:10pt; font-family:Times New Roman">&#8199;99.4</P></TD>
<TD VALIGN="bottom">&nbsp;&nbsp;</TD>
<TD VALIGN="top"><A HREF="http://www.sec.gov/Archives/edgar/data/1395937/000156459020037777/sndx-ex101_313.htm">Form of Stock Unit Agreement under 2015 Omnibus Incentive Plan (incorporated herein by reference to Exhibit 10.1 to the Company&#146;s Quarterly
 Report on Form <FONT STYLE="white-space:nowrap">10-Q,</FONT> SEC File <FONT STYLE="white-space:nowrap">No.&nbsp;001-37708,</FONT> as filed with the SEC on August&nbsp;6, 2020).</A></TD></TR>
<TR STYLE="font-size:1pt">
<TD HEIGHT="8"></TD>
<TD HEIGHT="8" COLSPAN="2"></TD></TR>
<TR STYLE="page-break-inside:avoid ; font-family:Times New Roman; font-size:10pt">
<TD VALIGN="top" NOWRAP> <P STYLE=" margin-top:0pt ; margin-bottom:0pt; margin-left:1.00em; text-indent:-1.00em; font-size:10pt; font-family:Times New Roman">&#8199;99.5</P></TD>
<TD VALIGN="bottom">&nbsp;&nbsp;</TD>
<TD VALIGN="top"><A HREF="http://www.sec.gov/Archives/edgar/data/1395937/000156459021012607/sndx-ex1014_191.htm">Form of Deferred Settlement Stock Unit Agreement under 2015 Omnibus Incentive Plan (incorporated herein by reference to Exhibit 10.14 to the
Company&#146;s Annual Report on Form <FONT STYLE="white-space:nowrap">10-K,</FONT> SEC File <FONT STYLE="white-space:nowrap">No.&nbsp;001-37708,</FONT> filed with the SEC on March&nbsp;12, 2021).</A></TD></TR>
<TR STYLE="font-size:1pt">
<TD HEIGHT="8"></TD>
<TD HEIGHT="8" COLSPAN="2"></TD></TR>
<TR STYLE="page-break-inside:avoid ; font-family:Times New Roman; font-size:10pt">
<TD VALIGN="top" NOWRAP> <P STYLE=" margin-top:0pt ; margin-bottom:0pt; margin-left:1.00em; text-indent:-1.00em; font-size:10pt; font-family:Times New Roman">&#8199;99.6</P></TD>
<TD VALIGN="bottom">&nbsp;&nbsp;</TD>
<TD VALIGN="top"><A HREF="http://www.sec.gov/Archives/edgar/data/0001395937/000119312516518181/d166957dex416.htm">2015 Employee Stock Purchase Plan (incorporated herein by reference to Exhibit 4.16 to the Company&#146;s Registration Statement on Form
<FONT STYLE="white-space:nowrap">S-8,</FONT> SEC File <FONT STYLE="white-space:nowrap">No.&nbsp;333-210412,</FONT> as filed with the SEC on March&nbsp;25, 2016). </A></TD></TR>
<TR STYLE="font-size:1pt">
<TD HEIGHT="8"></TD>
<TD HEIGHT="8" COLSPAN="2"></TD></TR>
<TR STYLE="page-break-inside:avoid ; font-family:Times New Roman; font-size:10pt">
<TD VALIGN="top" NOWRAP> <P STYLE=" margin-top:0pt ; margin-bottom:0pt; margin-left:1.00em; text-indent:-1.00em; font-size:10pt; font-family:Times New Roman">&#8199;99.7</P></TD>
<TD VALIGN="bottom">&nbsp;&nbsp;</TD>
<TD VALIGN="top"><A HREF="http://www.sec.gov/Archives/edgar/data/1395937/000095017024021253/sndx-ex10_16.htm">Syndax Pharmaceuticals, Inc. 2023 Inducement Plan (incorporated herein by reference to Exhibit 10.16 to the Company&#146;s Annual Report on Form
<FONT STYLE="white-space:nowrap">10-K,</FONT> SEC File <FONT STYLE="white-space:nowrap">No.&nbsp;001-37708,</FONT> as filed with the SEC on February&nbsp;27, 2024). </A></TD></TR>
<TR STYLE="font-size:1pt">
<TD HEIGHT="8"></TD>
<TD HEIGHT="8" COLSPAN="2"></TD></TR>
<TR STYLE="page-break-inside:avoid ; font-family:Times New Roman; font-size:10pt">
<TD VALIGN="top" NOWRAP> <P STYLE=" margin-top:0pt ; margin-bottom:0pt; margin-left:1.00em; text-indent:-1.00em; font-size:10pt; font-family:Times New Roman">&#8199;99.8</P></TD>
<TD VALIGN="bottom">&nbsp;&nbsp;</TD>
<TD VALIGN="top"><A HREF="http://www.sec.gov/Archives/edgar/data/1395937/000095017023002172/sndx-ex10_2.htm">Form of Option Agreement pursuant to the Syndax Pharmaceuticals, Inc. 2023 Inducement Plan (incorporated herein by reference to Exhibit 10.2 to
the Company&#146;s Current Report on Form <FONT STYLE="white-space:nowrap">8-K,</FONT> SEC File <FONT STYLE="white-space:nowrap">No.&nbsp;001-37708,</FONT> as filed with the SEC on February&nbsp;8, 2023).</A></TD></TR>
<TR STYLE="font-size:1pt">
<TD HEIGHT="8"></TD>
<TD HEIGHT="8" COLSPAN="2"></TD></TR>
<TR STYLE="page-break-inside:avoid ; font-family:Times New Roman; font-size:10pt">
<TD VALIGN="top" NOWRAP> <P STYLE=" margin-top:0pt ; margin-bottom:0pt; margin-left:1.00em; text-indent:-1.00em; font-size:10pt; font-family:Times New Roman">107</P></TD>
<TD VALIGN="bottom">&nbsp;&nbsp;</TD>
<TD VALIGN="top"><A HREF="d769709dexfilingfees.htm">Calculation of Filing Fee Table. </A></TD></TR>
</TABLE>
</DIV></Center>


<p style="margin-top:1em; margin-bottom:0em; page-break-before:always"> </p>
<HR SIZE="3" style="COLOR:#999999" WIDTH="100%" ALIGN="CENTER">


<Center><DIV STYLE="width:8.5in" align="left">
 <P STYLE="margin-top:0pt; margin-bottom:0pt; font-size:10pt; font-family:Times New Roman" ALIGN="center"><B><A NAME="sig"></A>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 <FONT STYLE="white-space:nowrap">S-8</FONT> and has duly caused this Registration Statement to be signed on its behalf by the undersigned, thereunto duly authorized, in the city of Waltham,
Commonwealth of Massachusetts, on February&nbsp;27, 2024. </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="7%"></TD>

<TD VALIGN="bottom" WIDTH="1%"></TD>
<TD WIDTH="92%"></TD></TR>


<TR STYLE="page-break-inside:avoid ; font-family:Times New Roman; font-size:10pt">
<TD VALIGN="top" COLSPAN="3"><B>S<SMALL>YNDAX</SMALL> P<SMALL>HARMACEUTICALS</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="page-break-inside:avoid ; font-family:Times New Roman; font-size:10pt">
<TD VALIGN="bottom">By:</TD>
<TD VALIGN="bottom" STYLE=" BORDER-BOTTOM:1px solid #000000">&nbsp;</TD>
<TD VALIGN="bottom" STYLE="BORDER-BOTTOM:1px solid #000000">/s/ Michael A. Metzger</TD></TR>
<TR STYLE="page-break-inside:avoid ; font-family:Times New Roman; font-size:10pt">
<TD VALIGN="bottom"></TD>
<TD VALIGN="bottom">&nbsp;</TD>
<TD VALIGN="bottom">Michael A. Metzger</TD></TR>
<TR STYLE="page-break-inside:avoid ; font-family:Times New Roman; font-size:10pt">
<TD VALIGN="bottom"></TD>
<TD VALIGN="bottom">&nbsp;</TD>
<TD VALIGN="bottom">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>KNOW ALL PERSONS BY THESE PRESENTS</B>, that each person whose signature appears below constitutes and appoints Michael A. Metzger and Luke
J. Albrecht, and each of them, his true and lawful <FONT STYLE="white-space:nowrap"><FONT STYLE="white-space:nowrap">attorney-in-fact</FONT></FONT> and agents, each with full power of substitution and resubstitution, for him or her and in his or her
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 <FONT STYLE="white-space:nowrap"><FONT STYLE="white-space:nowrap">attorneys-in-fact</FONT></FONT> 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 <FONT STYLE="white-space:nowrap"><FONT
STYLE="white-space:nowrap">attorneys-in-fact</FONT></FONT> 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, as amended, 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="38%"></TD>

<TD VALIGN="bottom"></TD>
<TD WIDTH="44%"></TD>

<TD VALIGN="bottom" WIDTH="1%"></TD>
<TD WIDTH="16%"></TD></TR>
<TR STYLE="page-break-inside:avoid ; 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="page-break-inside:avoid ; 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/ Michael A. Metzger</P>
<P STYLE="margin-top:0pt; margin-bottom:1pt; font-size:10pt; font-family:Times New Roman" ALIGN="center">Michael A. Metzger</P></TD>
<TD VALIGN="bottom">&nbsp;&nbsp;</TD>
<TD VALIGN="top" ALIGN="center"> <P STYLE="margin-top:0pt; margin-bottom:0pt; font-size:10pt; font-family:Times New Roman" ALIGN="center">Chief Executive Officer and Director</P>
<P STYLE="margin-top:0pt; margin-bottom:1pt; font-size:10pt; font-family:Times New Roman" ALIGN="center">(Principal Executive Officer)</P></TD>
<TD VALIGN="bottom">&nbsp;</TD>
<TD VALIGN="top" NOWRAP ALIGN="center">February&nbsp;27, 2024</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="page-break-inside:avoid ; 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/ Keith A. Goldan</P>
<P STYLE="margin-top:0pt; margin-bottom:1pt; font-size:10pt; font-family:Times New Roman" ALIGN="center">Keith A. Goldan</P></TD>
<TD VALIGN="bottom">&nbsp;&nbsp;</TD>
<TD VALIGN="top" ALIGN="center"> <P STYLE="margin-top:0pt; margin-bottom:0pt; font-size:10pt; font-family:Times New Roman" ALIGN="center">Chief Financial Officer</P>
<P STYLE="margin-top:0pt; margin-bottom:1pt; font-size:10pt; font-family:Times New Roman" ALIGN="center">(Principal Financial and Accounting Officer)</P></TD>
<TD VALIGN="bottom">&nbsp;</TD>
<TD VALIGN="top" NOWRAP ALIGN="center">February&nbsp;27, 2024</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="page-break-inside:avoid ; 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/ Dennis G. Podlesak</P>
<P STYLE="margin-top:0pt; margin-bottom:1pt; font-size:10pt; font-family:Times New Roman" ALIGN="center">Dennis G. Podlesak</P></TD>
<TD VALIGN="bottom">&nbsp;&nbsp;</TD>
<TD VALIGN="top" ALIGN="center">Chairman of the Board of Directors</TD>
<TD VALIGN="bottom">&nbsp;</TD>
<TD VALIGN="top" NOWRAP ALIGN="center">February&nbsp;27, 2024</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="page-break-inside:avoid ; 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/ Martin H. Huber, M.D.</P>
<P STYLE="margin-top:0pt; margin-bottom:1pt; font-size:10pt; font-family:Times New Roman" ALIGN="center">Martin H. Huber, M.D.</P></TD>
<TD VALIGN="bottom">&nbsp;&nbsp;</TD>
<TD VALIGN="top" ALIGN="center">Director</TD>
<TD VALIGN="bottom">&nbsp;</TD>
<TD VALIGN="top" NOWRAP ALIGN="center">February&nbsp;27, 2024</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="page-break-inside:avoid ; 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/ Jennifer Jarrett</P>
<P STYLE="margin-top:0pt; margin-bottom:1pt; font-size:10pt; font-family:Times New Roman" ALIGN="center">Jennifer Jarrett</P></TD>
<TD VALIGN="bottom">&nbsp;&nbsp;</TD>
<TD VALIGN="top" ALIGN="center">Director</TD>
<TD VALIGN="bottom">&nbsp;</TD>
<TD VALIGN="top" NOWRAP ALIGN="center">February&nbsp;27, 2024</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="page-break-inside:avoid ; 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/ Keith A. Katkin</P>
<P STYLE="margin-top:0pt; margin-bottom:1pt; font-size:10pt; font-family:Times New Roman" ALIGN="center">Keith A. Katkin</P></TD>
<TD VALIGN="bottom">&nbsp;&nbsp;</TD>
<TD VALIGN="top" ALIGN="center">Director</TD>
<TD VALIGN="bottom">&nbsp;</TD>
<TD VALIGN="top" NOWRAP ALIGN="center">February&nbsp;27, 2024</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="page-break-inside:avoid ; 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/ Pierre Legault</P>
<P STYLE="margin-top:0pt; margin-bottom:1pt; font-size:10pt; font-family:Times New Roman" ALIGN="center">Pierre Legault</P></TD>
<TD VALIGN="bottom">&nbsp;&nbsp;</TD>
<TD VALIGN="top" ALIGN="center">Director</TD>
<TD VALIGN="bottom">&nbsp;</TD>
<TD VALIGN="top" NOWRAP ALIGN="center">February&nbsp;27, 2024</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="page-break-inside:avoid ; 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 Meury</P>
<P STYLE="margin-top:0pt; margin-bottom:1pt; font-size:10pt; font-family:Times New Roman" ALIGN="center">William Meury</P></TD>
<TD VALIGN="bottom">&nbsp;&nbsp;</TD>
<TD VALIGN="top" ALIGN="center">Director</TD>
<TD VALIGN="bottom">&nbsp;</TD>
<TD VALIGN="top" NOWRAP ALIGN="center">February&nbsp;27, 2024</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="page-break-inside:avoid ; 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/ Briggs W. Morrison, M.D.</P>
<P STYLE="margin-top:0pt; margin-bottom:1pt; font-size:10pt; font-family:Times New Roman" ALIGN="center">Briggs W. Morrison, M.D.</P></TD>
<TD VALIGN="bottom">&nbsp;&nbsp;</TD>
<TD VALIGN="top" ALIGN="center">Director</TD>
<TD VALIGN="bottom">&nbsp;</TD>
<TD VALIGN="top" NOWRAP ALIGN="center">February&nbsp;27, 2024</TD></TR>
</TABLE>
</DIV></Center>

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S-8
As filed with the Securities and Exchange Commission on February 27, 2024
Registration No. 333-
UNITED STATES
SECURITIES
AND EXCHANGE COMMISSION
Washington, D.C. 20549
Form
S-8
REGISTRATION STATEMENT
UNDER
THE
SECURITIES ACT OF 1933
Syndax Pharmaceuticals, Inc.
(Exact name of registrant as specified in its charter)
Delaware
32-0162505
(State or other jurisdiction of
incorporation or organization)
(IRS employer
identification number)
35 Gatehouse Drive
Building D, Floor 3
Waltham, Massachusetts 02451
(781)
419-1400
(Address of principal executive offices)
2015 Omnibus
Incentive Plan
2015 Employee Stock Purchase Plan
2023 Inducement Plan
Inducement Stock Options
(Full titles of the plans)
Michael A.
Metzger
Chief Executive Officer
Syndax Pharmaceuticals, Inc.
35 Gatehouse Drive
Building D, Floor 3
Waltham, Massachusetts 02451
(781)
419-1400
(Name, address and telephone number of agent for service)
Laura A. Berezin
Jaime L. Chase
Cooley
LLP
1700 Seventh Avenue, Suite 1900
Seattle, Washington 98101
(206)
452-8700
Luke J. Albrecht
General Counsel & Secretary
Syndax Pharmaceuticals, Inc.
Building D, Floor 3
35
Gatehouse Drive
Waltham, Massachusetts 02451
(781)
419-1400
Indicate by check mark whether the registrant is a large accelerated filer, an accelerated filer, a
non-accelerated
filer, a smaller reporting company, or an emerging growth company. See the definitions of "large accelerated filer," "accelerated filer," "smaller reporting
company," and "emerging growth company" in Rule
12b-2
of the Exchange Act.
Large accelerated filer
☒
Accelerated filer
☐
Non-accelerated
filer
☐
Smaller reporting company
☐
Emerging growth company
☐
If an emerging growth company, indicate by check mark if the registrant has elected not to use the extended
transition period for complying with any new or revised financial accounting standards provided pursuant to Section 7(a)(2)(B) of the Securities Act. ☐
Explanatory Note
This Registration Statement on Form
S-8
("Registration Statement") is being filed for the purpose of
registering (i) 3,393,065 shares of the Registrant's common stock, par value $0.0001 per share ("Common Stock"), reserved and available for issuance under the Registrant's 2015 Omnibus Incentive Plan, (ii) 250,000 shares of the
Registrant's Common Stock, reserved and available for issuance under the Registrant's 2015 Employee Stock Purchase Plan, (iii) 1,075,750 shares of the Registrant's Common Stock, reserved and available for issuance under the
Registrant's 2023 Inducement Plan (the "Inducement Plan"), and (iv) 24,250 shares of common stock issuable upon the exercise of outstanding options granted to new employees as inducement awards in connection with the commencement of
employment pursuant to Nasdaq Listing Rule 5635(c)(4) pursuant to the Inducement Plan.
PART II
INFORMATION REQUIRED IN THE REGISTRATION STATEMENT
Item 3.
Incorporation of Documents by References
The Registrant previously registered shares of its Common Stock for issuance under the 2015 Plan and the ESPP under Registration Statements on Form
S-8
filed with the Securities and Exchange Commission on
March 25, 2016
(File
No. 333-210412),
August 25, 2017
(File
No. 
333-220172),
August 8, 2018
(File
No. 
333-226678),
August 7, 2019
(File
No. 
333-233083),
August 6, 2020
(File
No. 
333-241654),
August 9, 2021
(File
No. 
333-258628),
March 1, 2022
(File
No. 
333-263185)
and
February
28, 2023
(File
No. 333-270093).
Pursuant to General
Instruction E to Form
S-8,
this Registration Statement hereby incorporates by reference the contents of the Registration Statements referenced above.
Item 8.
Exhibits
The exhibits to this Registration Statement are listed below and incorporated by reference herein.
Exhibit
Number
Exhibit Description
4.1
Amended and Restated Certificate of Incorporation (incorporated herein by reference to Exhibit 3.1 to the Registrant's Current Report
 on Form
8-K,
SEC File
No. 001-37708,
filed with the SEC on March 8, 2016).
4.2
Certificate of Amendment to the Amended and Restated Certificate of Incorporation of the Company (incorporated herein by reference to Exhibit 3.1
to the Company's Current Report on Form
8-K
(File No.
001-37708),
as filed with the SEC on May
18, 2023).
4.3
Amended and Restated Bylaws (incorporated herein by reference to Exhibit 3.2 to the Registrant's Current Report on Form
8-K,
SEC File
No. 001-37708,
filed with the SEC on March 8, 2016).
5.1
Opinion of Cooley LLP.
23.1
Consent of Independent Registered Accounting Firm.
23.2
Consent of Cooley LLP (included in Exhibit 5.1).
24.1
Power of Attorney (included on the signature page to this Registration Statement).
99.1
2015 Omnibus Incentive Plan (incorporated herein by reference to Exhibit 4.13 to the Company's Registration Statement on Form
S-8,
SEC File
No. 333-210412,
as filed with the SEC on March 25, 2016).
99.2
Form of Incentive Stock Option Agreement under 2015 Omnibus Incentive Plan (incorporated herein by reference to Exhibit 10.13 to the Registrant's
 Registration Statement on Form
S-1,
SEC File
No. 333-208861,
filed with the SEC on January 4, 2016).
99.3
Form of
Non-Qualified
Option Agreement under 2015 Omnibus Incentive Plan (incorporated herein by reference
 to Exhibit 10.14 to the Registrant's Registration Statement on Form
S-1,
SEC File
No. 333-208861,
filed with the SEC on January 4, 2016).
99.4
Form of Stock Unit Agreement under 2015 Omnibus Incentive Plan (incorporated herein by reference to Exhibit 10.1 to the Company's Quarterly
 Report on Form
10-Q,
SEC File
No. 001-37708,
as filed with the SEC on August 6, 2020).
99.5
Form of Deferred Settlement Stock Unit Agreement under 2015 Omnibus Incentive Plan (incorporated herein by reference to Exhibit 10.14 to the
Company's Annual Report on Form
10-K,
SEC File
No. 001-37708,
filed with the SEC on March 12, 2021).
99.6
2015 Employee Stock Purchase Plan (incorporated herein by reference to Exhibit 4.16 to the Company's Registration Statement on Form
S-8,
SEC File
No. 333-210412,
as filed with the SEC on March 25, 2016).
99.7
Syndax Pharmaceuticals, Inc. 2023 Inducement Plan (incorporated herein by reference to Exhibit 10.16 to the Company's Annual Report on Form
10-K,
SEC File
No. 001-37708,
as filed with the SEC on February 27, 2024).
99.8
Form of Option Agreement pursuant to the Syndax Pharmaceuticals, Inc. 2023 Inducement Plan (incorporated herein by reference to Exhibit 10.2 to
the Company's Current Report on Form
8-K,
SEC File
No. 001-37708,
as filed with the SEC on February 8, 2023).
107
Calculation of Filing Fee Table.
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 Waltham,
Commonwealth of Massachusetts, on February 27, 2024.
S
YNDAX
P
HARMACEUTICALS
, I
NC
.
By:
/s/ Michael A. Metzger
Michael A. Metzger
Chief Executive Officer
POWER OF ATTORNEY
KNOW ALL PERSONS BY THESE PRESENTS
, that each person whose signature appears below constitutes and appoints Michael A. Metzger and Luke
J. Albrecht, and each of them, his true and lawful
attorney-in-fact
and agents, each with full power of substitution and resubstitution, for him or her and in his or her
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, as amended, this Registration Statement has been signed by the following persons
in the capacities and on the dates indicated.
Signature
Title
Date
/s/ Michael A. Metzger
Michael A. Metzger
Chief Executive Officer and Director
(Principal Executive Officer)
February 27, 2024
/s/ Keith A. Goldan
Keith A. Goldan
Chief Financial Officer
(Principal Financial and Accounting Officer)
February 27, 2024
/s/ Dennis G. Podlesak
Dennis G. Podlesak
Chairman of the Board of Directors
February 27, 2024
/s/ Martin H. Huber, M.D.
Martin H. Huber, M.D.
Director
February 27, 2024
/s/ Jennifer Jarrett
Jennifer Jarrett
Director
February 27, 2024
/s/ Keith A. Katkin
Keith A. Katkin
Director
February 27, 2024
/s/ Pierre Legault
Pierre Legault
Director
February 27, 2024
/s/ William Meury
William Meury
Director
February 27, 2024
/s/ Briggs W. Morrison, M.D.
Briggs W. Morrison, M.D.
Director
February 27, 2024