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<!-- Field: Rule-Page --><DIV STYLE="margin-top: 12pt; margin-bottom: 3pt; width: 100%"><DIV STYLE="font-size: 1pt; border-top: Black 1pt solid; border-bottom: Black 2pt solid">&nbsp;</DIV></DIV><!-- Field: /Rule-Page -->

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

<P STYLE="font: 10pt Times New Roman, Times, Serif; margin: 0; text-align: center"><B>As filed with the Securities and Exchange Commission
on May 1, 2024</B></P>

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

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

<P STYLE="font: 1pt Times New Roman, Times, Serif; margin: 0">&nbsp;</P>

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

<P STYLE="font: 14pt Times New Roman, Times, Serif; margin: 0; text-align: center"><B>UNITED STATES</B></P>

<P STYLE="font: 14pt Times New Roman, Times, Serif; margin: 0; text-align: center"><B>SECURITIES AND EXCHANGE COMMISSION</B></P>

<P STYLE="font: 10pt Times New Roman, Times, Serif; margin: 0; text-align: center"><B>Washington, D.C. 20549</B></P>

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

<P STYLE="font: 14pt Times New Roman, Times, Serif; margin: 0; text-align: center"><B>FORM S-8</B></P>

<P STYLE="font: 14pt Times New Roman, Times, Serif; margin: 0; text-align: center"><B>REGISTRATION STATEMENT</B></P>

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

<P STYLE="font: 10pt Times New Roman, Times, Serif; margin: 0; text-align: center"><B><I>THE SECURITIES ACT OF 1933</I></B></P>

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

<P STYLE="font: 14pt Times New Roman, Times, Serif; margin: 0; text-align: center"><B>SUMMIT THERAPEUTICS INC.</B></P>

<P STYLE="font: 10pt Times New Roman, Times, Serif; margin: 0; text-align: center"><B>(Exact Name of Registrant as Specified in Its Charter)</B></P>

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

<table cellspacing="0" cellpadding="0" style="width: 100%; border-collapse: collapse; font-size: 12pt">
  <TR>
    <td style="vertical-align: top; width: 49%; text-align: center"><FONT STYLE="font-size: 10pt"><B>Delaware</B></FONT></TD>
    <td style="vertical-align: bottom; width: 2%">&nbsp;</TD>
    <td style="vertical-align: top; width: 49%; text-align: center"><FONT STYLE="font-size: 10pt"><B>37-1979717</B></FONT></TD></TR>
  <TR>
    <td style="vertical-align: top">
    <P STYLE="font: 10pt Times New Roman, Times, Serif; margin: 0; text-align: center"><B>(State or Other Jurisdiction of</B></P>
    <P STYLE="font: 10pt Times New Roman, Times, Serif; margin: 0; text-align: center"><B>Incorporation or Organization)</B></P></TD>
    <td style="vertical-align: bottom">&nbsp;</TD>
    <td style="vertical-align: top; text-align: center"><FONT STYLE="font-size: 10pt"><B>(I.R.S. Employer<BR>
Identification No.)</B></FONT></TD></TR>
  <TR>
    <td>&nbsp;</TD>
    <TD COLSPAN="2">&nbsp;</TD></TR>
  <TR>
    <td style="vertical-align: top">
    <P STYLE="font: 10pt Times New Roman, Times, Serif; margin: 0; text-align: center"><B>601 Brickell Key Drive, Suite 1000</B></P>
    <P STYLE="font: 10pt Times New Roman, Times, Serif; margin: 0; text-align: center"><B>Miami, FL</B></P></TD>
    <td style="vertical-align: bottom">&nbsp;</TD>
    <td style="vertical-align: bottom; text-align: center"><FONT STYLE="font-size: 10pt"><B>33131</B></FONT></TD></TR>
  <TR>
    <td style="vertical-align: top; text-align: center"><FONT STYLE="font-size: 10pt"><B>(Address of Principal Executive Offices)</B></FONT></TD>
    <td style="vertical-align: bottom">&nbsp;</TD>
    <td style="vertical-align: top; text-align: center"><FONT STYLE="font-size: 10pt"><B>(Zip Code)</B></FONT></TD></TR>
  </TABLE>
<P STYLE="font: 10pt Times New Roman, Times, Serif; margin: 0; text-align: center"><B>&nbsp;</B></P>

<P STYLE="font: 10pt Times New Roman, Times, Serif; margin: 0; text-align: center"><B>2020 Stock Incentive Plan</B></P>

<P STYLE="font: 10pt Times New Roman, Times, Serif; margin: 0; text-align: center"><B>2020 Employee Stock Purchase Plan</B></P>

<P STYLE="font: 10pt Times New Roman, Times, Serif; margin: 0; text-align: center"><B>(Full Title of the Plan)</B></P>

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

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

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

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

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

<P STYLE="font: 10pt Times New Roman, Times, Serif; margin: 0; text-align: center"><B>601 Brickell Key Drive, Suite 1000</B></P>

<P STYLE="font: 10pt Times New Roman, Times, Serif; margin: 0; text-align: center"><B>Miami, FL 33131</B></P>

<P STYLE="font: 10pt Times New Roman, Times, Serif; margin: 0; text-align: center"><B>(650) 460-8308</B></P>

<P STYLE="font: 12pt Times New Roman, Times, Serif; margin: 0; text-align: center; text-indent: 0.5in">&nbsp;</P>

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

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

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

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

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

<P STYLE="font: 10pt Times New Roman, Times, Serif; margin: 0; text-align: center"><B>601 Brickell Key Drive, Suite 1000</B></P>

<P STYLE="font: 10pt Times New Roman, Times, Serif; margin: 0; text-align: center"><B>Miami, FL 33131</B></P>

<P STYLE="font: 10pt Times New Roman, Times, Serif; margin: 0; text-align: center"><B>(650) 460-8308</B></P>

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

<P STYLE="font: 10pt Times New Roman, Times, Serif; margin: 0; text-align: center"><B>(Name, Address and Telephone Number, Including Area
Code, of Agent For Service)</B></P>

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

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

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

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

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

<P STYLE="font: 10pt Times New Roman, Times, Serif; margin: 0; text-align: center"><B>45 Rockefeller Plaza </B></P>

<P STYLE="font: 10pt Times New Roman, Times, Serif; margin: 0; text-align: center"><B>New York, NY 10111 </B></P>

<P STYLE="font: 10pt Times New Roman, Times, Serif; margin: 0; text-align: center"><B>Tel: (212) 589-4233</B></P>

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

<p style="font: 10pt Times New Roman, Times, Serif; margin: 0pt 0pt 9pt"><font style="font-family: Times New Roman, Times, Serif; font-size: 10pt">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 &ldquo;large accelerated filer,&rdquo; &ldquo;accelerated filer,&rdquo;
&ldquo;smaller reporting company&rdquo; and &ldquo;emerging growth company&rdquo; in Rule 12b-2 of the Exchange Act.</font></P>

<table cellspacing="0" cellpadding="0" style="font: 10pt Times New Roman, Times, Serif; width: 100%; border-collapse: collapse">
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    <td style="font: 10pt Times New Roman, Times, Serif; width: 20%"><font style="font-family: Times New Roman, Times, Serif; font-size: 10pt">Large accelerated filer</font></TD>
    <td style="font: 10pt Times New Roman, Times, Serif; width: 50%"><font style="font-family: Times New Roman, Times, Serif; font-size: 10pt">&#9744;</font></TD>
    <td style="font: 10pt Times New Roman, Times, Serif; width: 24%"><font style="font-family: Times New Roman, Times, Serif; font-size: 10pt">Accelerated filer</font></TD>
    <td style="font: 10pt Times New Roman, Times, Serif; width: 6%"><font style="font-family: Times New Roman, Times, Serif; font-size: 10pt">&#9744;</font></TD></TR>
  <tr style="font: 10pt Times New Roman, Times, Serif">
    <td style="font: 10pt Times New Roman, Times, Serif"><font style="font-family: Times New Roman, Times, Serif; font-size: 10pt">&nbsp;</font></TD>
    <td style="font: 10pt Times New Roman, Times, Serif"><font style="font-family: Times New Roman, Times, Serif; font-size: 10pt">&nbsp;</font></TD>
    <td style="font: 10pt Times New Roman, Times, Serif"><font style="font-family: Times New Roman, Times, Serif; font-size: 10pt">&nbsp;</font></TD>
    <td style="font: 10pt Times New Roman, Times, Serif"><font style="font-family: Times New Roman, Times, Serif; font-size: 10pt">&nbsp;</font></TD></TR>
  <tr style="font: 10pt Times New Roman, Times, Serif; vertical-align: bottom">
    <td style="font: 10pt Times New Roman, Times, Serif"><font style="font-family: Times New Roman, Times, Serif; font-size: 10pt">Non-accelerated filer</font></TD>
    <td style="font: 10pt Times New Roman, Times, Serif"><font style="font-family: Times New Roman, Times, Serif; font-size: 10pt">&#9746;</font></TD>
    <td style="font: 10pt Times New Roman, Times, Serif"><font style="font-family: Times New Roman, Times, Serif; font-size: 10pt">Smaller reporting company</font></TD>
    <td style="font: 10pt Times New Roman, Times, Serif"><font style="font-family: Times New Roman, Times, Serif; font-size: 10pt">&#9746;</font></TD></TR>
  <tr style="font: 10pt Times New Roman, Times, Serif; vertical-align: bottom">
    <td style="font: 10pt Times New Roman, Times, Serif"><font style="font-family: Times New Roman, Times, Serif; font-size: 10pt">&nbsp;</font></TD>
    <td style="font: 10pt Times New Roman, Times, Serif"><font style="font-family: Times New Roman, Times, Serif; font-size: 10pt">&nbsp;</font></TD>
    <td style="font: 10pt Times New Roman, Times, Serif"><font style="font-family: Times New Roman, Times, Serif; font-size: 10pt">&nbsp;</font></TD>
    <td style="font: 10pt Times New Roman, Times, Serif"><font style="font-family: Times New Roman, Times, Serif; font-size: 10pt">&nbsp;</font></TD></TR>
  <tr style="font: 10pt Times New Roman, Times, Serif; vertical-align: bottom">
    <td style="font: 10pt Times New Roman, Times, Serif"><font style="font-family: Times New Roman, Times, Serif; font-size: 10pt">&nbsp;</font></TD>
    <td style="font: 10pt Times New Roman, Times, Serif"><font style="font-family: Times New Roman, Times, Serif; font-size: 10pt">&nbsp;</font></TD>
    <td style="font: 10pt Times New Roman, Times, Serif"><font style="font-family: Times New Roman, Times, Serif; font-size: 10pt">Emerging growth company</font></TD>
    <td style="font: 10pt Times New Roman, Times, Serif"><font style="font-family: Times New Roman, Times, Serif; font-size: 10pt">&#9744;</font></TD></TR>
  </TABLE>
<p style="font: 10pt Times New Roman, Times, Serif; margin: 0"><font style="font-family: Times New Roman, Times, Serif; font-size: 10pt">&nbsp;</font></P>

<p style="font: 10pt Times New Roman, Times, Serif; margin: 0"><font style="font-family: Times New Roman, Times, Serif; font-size: 10pt">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.&nbsp;&uml;</font></P>

<p style="font: 10pt Times New Roman, Times, Serif; margin: 0"><font style="font-family: Times New Roman, Times, Serif; font-size: 10pt">&nbsp;</font></P>

<P STYLE="font: 1pt Times New Roman, Times, Serif; margin: 0">&nbsp;</P>

<P STYLE="font: 12pt Times New Roman, Times, Serif; margin: 0">&nbsp;</P>

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

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

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

<P STYLE="font: 10pt Times New Roman, Times, Serif; margin: 0; text-align: justify">This Registration Statement on Form S-8 is filed for
the purposes of registering 90,800,000 and 825,751 additional shares of common stock, par value $0.01 per share (&ldquo;Common Stock&rdquo;)
of Summit Therapeutics Inc. (the &ldquo;Registrant&rdquo;) that may be issued pursuant to the Summit Therapeutics Inc. 2020 Stock Incentive
Plan (the &ldquo;2020 Plan&rdquo;) and the Summit Therapeutics Inc. 2020 Employee Stock Purchase Plan (&ldquo;2020 ESPP&rdquo;), respectively.</P>

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

<P STYLE="font: 10pt Times New Roman, Times, Serif; margin: 0; text-align: justify">The number of shares of Common Stock reserved and
available for issuance under the 2020 Plan is subject to an automatic annual increase on each January 1, beginning with the fiscal year
ending December 31, 2021 and continuing for each fiscal year until, and including, the fiscal year ending December 31, 2030, by an amount
equal to the least of (i) 6,400,000 shares of Common Stock, (ii) <FONT STYLE="background-color: white">4% of the outstanding shares on
such date and (iii) an amount determined by the board of directors of the Registrant (the &ldquo;Board&rdquo;).</FONT></P>

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

<P STYLE="font: 10pt Times New Roman, Times, Serif; margin: 0; text-align: justify">Accordingly, on (i) January 1, 2023, the number of
shares of Common Stock reserved and available for issuance under the 2020 Plan increased by 6,400,000, and (ii) January 1, 2024, the number
of shares of Common Stock reserved and available for issuance under the 2020 Plan increased by 6,400,000. In addition, the 2020 Plan has
been amended twice with the approval of the Registrant&rsquo;s stockholders to increase the number of shares of Common Stock reserved and
available for issuance thereunder: (i) by 8,000,000 shares pursuant to the approval of stockholders at a Special Meeting of stockholders
held on July 27, 2022 and (ii) by 70,000,000 shares pursuant to the approval of stockholders at a Special Meeting of Stockholders held
on October 12, 2023. This Registration Statement registers both (i) the additional 12,800,000 shares of Common Stock reserved and available
for issuance in accordance with the automatic annual increase provided for under the terms of the 2020 Plan and (ii) the additional 78,000,000
shares of Common Stock reserved and available for issuance pursuant to amendments to the 2020 Plan previously approved by stockholders.
The additional shares are of the same class as other securities relating to the 2020 Plan for which the Registrant&rsquo;s registration
statements on Form S-8, Registration No. 333-249313 and Registration No. 333-264163, filed on October 5, 2020 and April 6, 2022 respectively,
are effective.</P>

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

<P STYLE="font: 10pt Times New Roman, Times, Serif; margin: 0; text-align: justify">The number of shares of Common Stock reserved and
available for issuance under the 2020 ESPP is subject to an automatic annual increase <FONT STYLE="background-color: white">on each fiscal
year commencing January 1, 2021 and continuing for each fiscal year until, and including the fiscal year commencing on, January 1, 2030
equal to the least of (i)&nbsp;1,600,000&nbsp;shares of common stock, (ii)&nbsp;1% of the common shares outstanding on such date and (iii)
an amount as determined by the Board. </FONT></P>

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

<P STYLE="font: 10pt Times New Roman, Times, Serif; margin: 0; text-align: justify">Effective (i) January 1, 2021, the Board determined
to increase the number of shares of Common Stock reserved and available for issuance under the 2020 ESPP by 825,751, (ii) January 1, 2022,
the Board determined to increase the number of shares of Common Stock reserved and available for issuance under the 2020 ESPP by 980,000
(which shares have been previously registered), and (iii) January 1, 2023 and 2024, the Board determined that there would be no increase
in the number of shares of Common Stock reserved and available for issuance under the 2020 ESPP. This Registration Statement registers
the additional 825,751 shares of Common Stock reserved and available for issuance in accordance with the automatic annual increase provided
for under the terms of the 2020 ESPP. The shares of Common Stock shall be of the same class as other securities relating to the 2020 ESPP
for which the Registrant&rsquo;s registration statement on Form S-8, Registration No. 333-264163, filed on April 6, 2022 is effective.</P>

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

<P STYLE="font: 12pt Times New Roman, Times, Serif; margin: 0">&nbsp;<FONT STYLE="font-size: 10pt">&nbsp;</FONT></P>

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

<P STYLE="font: 10pt Times New Roman, Times, Serif; margin: 0; text-align: center"><B>INFORMATION REQUIRED IN THE SECTION 10(a) PROSPECTUS</B></P>

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

<P STYLE="font: 10pt Times New Roman, Times, Serif; margin: 0; text-align: justify"><B>Item 1. Plan Information.</B></P>

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

<P STYLE="font: 10pt Times New Roman, Times, Serif; margin: 0; text-align: justify">The information required by Item 1 is included in
documents sent or given to participants in the plans covered by this registration statement pursuant to Rule 428(b)(1) of the Securities
Act.</P>

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

<P STYLE="font: 10pt Times New Roman, Times, Serif; margin: 0; text-align: justify"><B>Item 2. Registrant Information and Employee Plan
Annual Information.</B></P>

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

<P STYLE="font: 10pt Times New Roman, Times, Serif; margin: 0; text-align: justify">The written statement required by Item 2 is included
in documents sent or given to participants in the plans covered by this registration statement pursuant to Rule 428(b)(1) of the Securities
Act.</P>

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


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

<p style="font: 10pt Times New Roman, Times, Serif; margin: 0; text-align: center"><b>PART II</B></P>

<P STYLE="font: 10pt Times New Roman, Times, Serif; margin: 0; text-align: center"><B>INFORMATION REQUIRED IN THE REGISTRATION STATEMENT</B></P>

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

<P STYLE="font: 10pt Times New Roman, Times, Serif; margin: 0; text-align: justify"><B>Item 3. Incorporation of Documents by Reference.</B></P>

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

<P STYLE="font: 10pt Times New Roman, Times, Serif; margin: 0; text-align: justify">The registrant is subject to the informational and
reporting requirements of Sections 13(a), 14, and 15(d) of the Exchange Act, and in accordance therewith files reports, proxy statements
and other information with the Securities and Exchange Commission (the &ldquo;Commission&rdquo;). The following documents, which have
been filed with the Commission, are incorporated in this registration statement by reference:</P>

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

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  <TR STYLE="vertical-align: top">
    <TD STYLE="width: 4%">&nbsp;</TD>
    <TD STYLE="width: 4%; text-align: justify"><FONT STYLE="font-size: 10pt">(a)</FONT></TD>
    <TD STYLE="width: 92%; text-align: justify"><FONT STYLE="font-size: 10pt">The registrant&rsquo;s Annual Report on Form 10-K for the fiscal year ended December 31, 2023, filed on&nbsp;February 20, 2024.</FONT></TD></TR>
  </TABLE>
<P STYLE="font: 10pt Times New Roman, Times, Serif; margin: 0; text-align: justify">&nbsp;</P>

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  <TR STYLE="vertical-align: top">
    <TD STYLE="width: 4%">&nbsp;</TD>
    <TD STYLE="width: 4%; text-align: justify"><FONT STYLE="font-size: 10pt">(b)</FONT></TD>
    <TD STYLE="width: 92%">
    <P STYLE="font: 10pt Times New Roman, Times, Serif; margin: 0; text-align: justify">The registrant&rsquo;s Quarterly Report on Form 10-Q
    for the fiscal quarter ended March 31, 2024, filed on May 1, 2024.</P>
    <P STYLE="font: 10pt Times New Roman, Times, Serif; margin: 0; text-align: justify">&nbsp;</P></TD></TR>
  <TR STYLE="vertical-align: top">
    <TD STYLE="text-align: justify">&nbsp;</TD>
    <TD STYLE="text-align: justify"><FONT STYLE="font-size: 10pt">(c)</FONT></TD>
    <TD STYLE="text-align: justify"><FONT STYLE="font-size: 10pt">The registrant&rsquo;s Current Reports on Form 8-K filed on&nbsp;January 3, 2024, February 8, 2024, March 5, 2024, March 22, 2024, April 3, 2024, and April 11, 2024.</FONT></TD></TR>
  </TABLE>
<P STYLE="font: 10pt Times New Roman, Times, Serif; margin: 0 0 0 0.5in; text-align: justify">&nbsp;</P>

<TABLE CELLSPACING="0" CELLPADDING="0" STYLE="width: 100%; font-size: 12pt">
  <TR STYLE="vertical-align: top">
    <TD STYLE="width: 4%">&nbsp;</TD>
    <TD STYLE="width: 4%; text-align: justify"><FONT STYLE="font-size: 10pt">(d)</FONT></TD>
    <TD STYLE="width: 92%; text-align: justify"><FONT STYLE="font-size: 10pt">The description of the securities contained in the registrant&rsquo;s Current Report on Form 8-K dated&nbsp;September 18, 2020, including any amendment or report filed for the purposes of updating such description.</FONT></TD></TR>
  </TABLE>
<P STYLE="font: 10pt Times New Roman, Times, Serif; margin: 0; text-align: justify">&nbsp;</P>

<P STYLE="font: 10pt Times New Roman, Times, Serif; margin: 0; text-align: justify">All documents subsequently filed by the registrant
pursuant to Sections 13(a), 13(c), 14 and 15(d) of the Exchange Act, prior to the filing of a post-effective amendment to this registration
statement which indicates that all securities offered hereby have been sold or which deregisters all securities then remaining unsold,
shall be deemed to be incorporated by reference in this registration statement and to be part hereof from the date of the filing of such
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 the purposes of this registration statement to the extent that a statement contained herein or in any other subsequently
filed document which also is or is deemed to be incorporated by reference herein modifies or supersedes such statement. Any 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: 10pt Times New Roman, Times, Serif; margin: 0">&nbsp;</P>

<P STYLE="font: 10pt Times New Roman, Times, Serif; margin: 0"><B>Item 4. Description of Securities.</B></P>

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

<P STYLE="font: 10pt Times New Roman, Times, Serif; margin: 0">Not applicable.</P>

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

<P STYLE="font: 10pt Times New Roman, Times, Serif; margin: 0; text-align: justify"><B>Item 5. Interests of Named Experts and Counsel.</B></P>

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

<P STYLE="font: 10pt Times New Roman, Times, Serif; margin: 0; text-align: justify">Not applicable.</P>

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

<P STYLE="font: 10pt Times New Roman, Times, Serif; margin: 0; text-align: justify"><B>Item 6. Indemnification of Directors and Officers.</B></P>

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

<P STYLE="font: 10pt Times New Roman, Times, Serif; margin: 0; text-align: justify">Section 102 of the Delaware General Corporation Law
permits a corporation to eliminate the personal liability of directors of a corporation to the corporation or its stockholders for monetary
damages for a breach of fiduciary duty as a director, except where the director breached his or her duty of loyalty, failed to act in
good faith, engaged in intentional misconduct or knowingly violated a law, authorized the payment of a dividend or approved a stock repurchase
in violation of Delaware corporate law or obtained an improper personal benefit. The registrant&rsquo;s certificate of incorporation provides
that none of its directors shall be personally liable to the registrant or its stockholders for monetary damages for any breach of fiduciary
duty as director, notwithstanding any provision of law imposing such liability, except to the extent that the Delaware General Corporation
Law prohibits the elimination or limitation of liability of directors for breaches of fiduciary duty.</P>

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

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


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

<p style="font: 10pt Times New Roman, Times, Serif; margin: 0; text-align: justify">Section 145 of the Delaware General Corporation Law
provides that a corporation has the power to indemnify a director, officer, employee or agent of the corporation and certain other persons
serving at the request of the corporation in related capacities against expenses (including attorneys&rsquo; fees), judgments, fines and
amounts paid in settlements actually and reasonably incurred by the
person in connection with an action, suit or proceeding to which he or she is or is threatened to be made a party by reason of such position,
if such person acted in good faith and in a manner he or she reasonably believed to be in or not opposed to the best interests of the
corporation and, in any criminal action or proceeding, had no reasonable cause to believe his or her conduct was unlawful, except that,
in the case of actions brought by or in the right of the corporation, no indemnification shall be made with respect to any claim, issue
or matter as to which such person shall have been adjudged to be liable to the corporation unless and only to the extent that the Court
of Chancery or other adjudicating court determines that, despite the adjudication of liability but in view of all of the circumstances
of the case, such person is fairly and reasonably entitled to indemnity for such expenses which the Court of Chancery or such other court
shall deem proper.</P>

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

<P STYLE="font: 10pt Times New Roman, Times, Serif; margin: 0; text-align: justify">The registrant&rsquo;s certificate of incorporation
provides that the registrant will indemnify each person who was or is a party or threatened to be made a party to or is involved in any
threatened, pending or completed action, suit or proceeding<B>,&nbsp;</B>whether civil, criminal, administrative or investigative (other
than an action by or in the right of the registrant) by reason of the fact that he or she is or was a director or officer of the registrant,
or is or was serving at the registrant&rsquo;s request as a director or officer of another corporation, partnership, joint venture, trust
or other enterprise to the fullest extent permitted by the Delaware General Corporation Law. The registrant&rsquo;s certificate of incorporation
provides that any reasonable, documented, out-pocket expenses must be advanced to these indemnitees under certain circumstances.</P>

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

<P STYLE="font: 10pt Times New Roman, Times, Serif; margin: 0; text-align: justify">The indemnification provisions contained in the registrant&rsquo;s
certificate of incorporation are not exclusive. In addition, the registrant has entered into indemnification agreements with each of its
directors and executive officers. Each indemnification agreement provides that the registrant will indemnify the director or executive
officer to the fullest extent permitted by law for claims arising in his or her capacity as a director or executive officer, provided
that he or she acted in good faith and in a manner that he or she reasonably believed to be in, or not opposed to, the registrant&rsquo;s
best interests and, with respect to any criminal proceeding, had no reasonable cause to believe that his or her conduct was unlawful.
In the event that the registrant does not assume the defense of a claim against a director or executive officer, the registrant is required
to advance his or her expenses in connection with his or her defense, provided that he or she undertakes to repay all amounts advanced
if it is ultimately determined that he or she is not entitled to be indemnified by the registrant.</P>

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

<P STYLE="font: 10pt Times New Roman, Times, Serif; margin: 0; text-align: justify">In addition, the registrant maintains standard policies
of insurance under which coverage is provided to the registrant&rsquo;s directors and officers against losses arising from claims made
by reason of breach of duty or other wrongful act, and to the registrant with respect to payments which may be made by the registrant
to such directors and officers pursuant to the above indemnification provisions or otherwise as a matter of law.</P>

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

<P STYLE="font: 10pt Times New Roman, Times, Serif; margin: 0; text-align: justify"><B>Item 7. Exemption from Registration Claimed.</B></P>

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

<P STYLE="font: 10pt Times New Roman, Times, Serif; margin: 0; text-align: justify">Not applicable.</P>

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

<P STYLE="font: 10pt Times New Roman, Times, Serif; margin: 0; text-align: justify"><B>Item 8. Exhibits.</B></P>

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

<P STYLE="font: 10pt Times New Roman, Times, Serif; margin: 0; text-align: justify">The following exhibits are incorporated herein by
reference:</P>

<TABLE CELLSPACING="0" CELLPADDING="0" STYLE="width: 100%; border-collapse: collapse; font-size: 12pt">
  <TR>
    <TD STYLE="width: 7%">&nbsp;</TD>
    <TD STYLE="vertical-align: bottom; width: 2%">&nbsp;</TD>
    <TD STYLE="width: 91%">&nbsp;</TD></TR>
  <TR STYLE="vertical-align: bottom">
    <TD STYLE="white-space: nowrap; text-align: center"><font style="font-size: 10pt"><b>Number</b></font></TD>
    <TD><b>&nbsp;</b></TD>
    <TD STYLE="white-space: nowrap; text-align: center"><font style="font-size: 10pt"><b>Description</b></font></TD></TR>
  <TR>
    <TD>&nbsp;</TD>
    <TD COLSPAN="2">&nbsp;</TD></TR>
  <TR>
    <TD STYLE="white-space: nowrap; vertical-align: top"><FONT STYLE="font-size: 10pt"><A HREF="https://www.sec.gov/Archives/edgar/data/1599298/000119312520248702/d76627dex31.htm">4.1</A></FONT></TD>
    <TD STYLE="vertical-align: bottom">&nbsp;</TD>
    <TD STYLE="vertical-align: top"><FONT STYLE="font-size: 10pt"><A HREF="https://www.sec.gov/Archives/edgar/data/1599298/000119312520248702/d76627dex31.htm">Restated Certificate of Incorporation of the registrant (incorporated by reference to Exhibit 3.1 to the registrant&rsquo;s Current Report on Form 8-K (File No. 001-36866), filed with the Securities and Exchange Commission on September 18, 2020).</A></FONT></TD></TR>
  <TR>
    <TD STYLE="white-space: nowrap; vertical-align: top">&nbsp;</TD>
    <TD STYLE="vertical-align: bottom">&nbsp;</TD>
    <TD STYLE="vertical-align: top">&nbsp;</TD></TR>
  <TR>
    <TD STYLE="white-space: nowrap; vertical-align: top"><FONT STYLE="font-size: 10pt"><A HREF="https://www.sec.gov/Archives/edgar/data/1599298/000159929822000086/summittherapeuticsinc-de.htm">4.2</A></FONT></TD>
    <TD STYLE="vertical-align: bottom">&nbsp;</TD>
    <TD STYLE="vertical-align: top"><FONT STYLE="font-size: 10pt"><A HREF="https://www.sec.gov/Archives/edgar/data/1599298/000159929822000086/summittherapeuticsinc-de.htm">Amendment to Restated Certificate of Incorporation of Summit Therapeutics Inc., as filed with the Delaware Secretary of State on July 27, 2022 (incorporated by reference to Exhibit 3.1 of Form 8-K filed by the Registrant on July 29, 2022, File No. 001-36866).</A></FONT></TD></TR>
  <TR>
    <TD STYLE="white-space: nowrap; vertical-align: top">&nbsp;</TD>
    <TD STYLE="vertical-align: bottom">&nbsp;</TD>
    <TD STYLE="vertical-align: top">&nbsp;</TD></TR>
  <TR>
    <TD STYLE="white-space: nowrap; vertical-align: top"><FONT STYLE="font-size: 10pt"><A HREF="https://www.sec.gov/Archives/edgar/data/1599298/000159929823000012/exhibit51summittherapeut.htm">4.3</A></FONT></TD>
    <TD STYLE="vertical-align: bottom">&nbsp;</TD>
    <TD STYLE="vertical-align: top"><FONT STYLE="font-size: 10pt"><A HREF="https://www.sec.gov/Archives/edgar/data/1599298/000159929823000012/exhibit51summittherapeut.htm">Amendment No. 2 to Restated Certificate of Incorporation, dated January 19, 2023 (incorporated by reference to Exhibit 5.1 of Form 8-K filed by the Registrant on January 20, 2023, File No. 001-36866).</A></FONT></TD></TR>
  <TR>
    <TD>&nbsp;</TD>
    <TD COLSPAN="2">&nbsp;</TD></TR>
  </TABLE>

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<P STYLE="font: 12pt Times New Roman, Times, Serif; margin: 0"></P>

<TABLE CELLSPACING="0" CELLPADDING="0" STYLE="width: 100%; border-collapse: collapse; font-size: 12pt">
  <tr>
    <td style="white-space: nowrap; vertical-align: top">&nbsp;</td>
    <td style="vertical-align: bottom">&nbsp;</td>
    <td style="vertical-align: top">&nbsp;</td></tr>
  <TR>
    <TD STYLE="white-space: nowrap; vertical-align: top; width: 7%"><FONT STYLE="font-size: 10pt"><A HREF="https://www.sec.gov/Archives/edgar/data/1599298/000119312520248702/d76627dex32.htm">4.4</A></FONT></TD>
    <TD STYLE="vertical-align: bottom; width: 2%">&nbsp;</TD>
    <TD STYLE="vertical-align: top; width: 91%"><FONT STYLE="font-size: 10pt"><A HREF="https://www.sec.gov/Archives/edgar/data/1599298/000119312520248702/d76627dex32.htm">Amended and Restated Bylaws of the registrant (incorporated by reference to Exhibit 3.2 to the registrant&rsquo;s Current Report on Form 8-K (File No. 001-36866), filed with the Securities and Exchange Commission on September 18, 2020).</A></FONT></TD></TR>
  <TR>
    <TD>&nbsp;</TD>
    <TD COLSPAN="2">&nbsp;</TD></TR>
  <TR>
    <TD STYLE="white-space: nowrap; vertical-align: top"><FONT STYLE="font-size: 10pt"><A HREF="ex5-1.htm">5.1</A></FONT></TD>
    <TD STYLE="vertical-align: bottom">&nbsp;</TD>
    <TD STYLE="vertical-align: top"><FONT STYLE="font-size: 10pt"><A HREF="ex5-1.htm">Opinion of BakerHostetler LLP, counsel to the registrant.</A></FONT></TD></TR>
  <TR>
    <TD>&nbsp;</TD>
    <TD COLSPAN="2">&nbsp;</TD></TR>
  <TR>
    <TD STYLE="white-space: nowrap; vertical-align: top"><FONT STYLE="font-size: 10pt"><a href="ex5-1.htm">23.1</a></FONT></TD>
    <TD STYLE="vertical-align: bottom">&nbsp;</TD>
    <TD STYLE="vertical-align: top"><FONT STYLE="font-size: 10pt"><a href="ex5-1.htm">Consent of BakerHostetler LLP (included in Exhibit 5.1).</a></FONT></TD></TR>
  <TR>
    <TD STYLE="white-space: nowrap; vertical-align: top">&nbsp;</TD>
    <TD STYLE="vertical-align: bottom">&nbsp;</TD>
    <TD STYLE="vertical-align: top">&nbsp;</TD></TR>
  <TR>
    <TD STYLE="white-space: nowrap; vertical-align: top"><FONT STYLE="font-size: 10pt"><A HREF="ex23-2.htm">23.2</A></FONT></TD>
    <TD STYLE="vertical-align: bottom">&nbsp;</TD>
    <TD STYLE="vertical-align: top"><FONT STYLE="font-size: 10pt"><A HREF="ex23-2.htm">Consent of PricewaterhouseCoopers LLP, independent registered public accounting firm for the registrant.</A></FONT></TD></TR>
  <TR>
    <TD STYLE="white-space: nowrap; vertical-align: top">&nbsp;</TD>
    <TD STYLE="vertical-align: bottom">&nbsp;</TD>
    <TD STYLE="vertical-align: top">&nbsp;</TD></TR>
  <TR>
    <TD STYLE="white-space: nowrap; vertical-align: top"><FONT STYLE="font-size: 10pt"><a href="#POA">24</a></FONT></TD>
    <TD STYLE="vertical-align: bottom">&nbsp;</TD>
    <TD STYLE="vertical-align: top"><FONT STYLE="font-size: 10pt"><a href="#POA">Powers of attorney (included on the signature pages of this registration statement).</a></FONT></TD></TR>
  <TR>
    <TD STYLE="white-space: nowrap; vertical-align: top">&nbsp;</TD>
    <TD STYLE="vertical-align: bottom">&nbsp;</TD>
    <TD STYLE="vertical-align: top">&nbsp;</TD></TR>
  <TR>
    <TD STYLE="white-space: nowrap; vertical-align: top"><FONT STYLE="font-size: 10pt"><A HREF="ex99-1.htm">99.1</A></FONT></TD>
    <TD STYLE="vertical-align: bottom">&nbsp;</TD>
    <TD STYLE="vertical-align: top"><FONT STYLE="font-size: 10pt"><A HREF="ex99-1.htm">2020 Stock Incentive Plan (as amended and restated as of October 12, 2023).</A></FONT></TD></TR>
  <TR>
    <TD>&nbsp;</TD>
    <TD COLSPAN="2">&nbsp;</TD></TR>
  <TR>
    <TD STYLE="white-space: nowrap; vertical-align: top"><FONT STYLE="font-size: 10pt"><A HREF="https://www.sec.gov/Archives/edgar/data/1599298/000119312520248702/d76627dex103.htm">99.2</A></FONT></TD>
    <TD STYLE="vertical-align: bottom">&nbsp;</TD>
    <TD STYLE="vertical-align: top">
    <P STYLE="font: 10pt Times New Roman, Times, Serif; margin: 0"><A HREF="https://www.sec.gov/Archives/edgar/data/1599298/000119312520248702/d76627dex103.htm">2020 Employee Stock Purchase Plan (incorporated by reference to Exhibit 10.3 to the Registrant&rsquo;s Current Report on Form 8-K (File No. 001-36866), filed with the Securities and Exchange Commission on September 18, 2020).</A></P>
    <P STYLE="font: 10pt Times New Roman, Times, Serif; margin: 0">&nbsp;</P></TD></TR>
  <TR>
    <TD STYLE="white-space: nowrap; vertical-align: top"><FONT STYLE="font-size: 10pt"><A HREF="ex107.htm">107</A></FONT></TD>
    <TD STYLE="vertical-align: bottom">&nbsp;</TD>
    <TD STYLE="vertical-align: top"><FONT STYLE="font-size: 10pt"><A HREF="ex107.htm">Filing Fee Table.</A></FONT></TD></TR>
  </TABLE>
<P STYLE="font: 10pt Times New Roman, Times, Serif; margin: 0"><B>&nbsp;</B></P>

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

<P STYLE="font: 10pt Times New Roman, Times, Serif; margin: 0"><B>Item 9. Undertakings.</B></P>

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

<P STYLE="font: 10pt Times New Roman, Times, Serif; margin: 0; text-align: justify">1.&nbsp;<I>Item 512(a) of Regulation S-K</I>. The
undersigned registrant hereby undertakes:</P>

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

<P STYLE="font: 10pt Times New Roman, Times, Serif; margin: 0; text-align: justify">(1) To file, during any period in which offers
or sales are being made, a post-effective amendment to this registration statement:</P>

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

<P STYLE="font: 10pt Times New Roman, Times, Serif; margin: 0; text-align: justify">(i) To include any prospectus required by Section
10(a)(3) of the Securities Act;</P>

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

<P STYLE="font: 10pt Times New Roman, Times, Serif; margin: 0; text-align: justify">(ii) To reflect in the prospectus any facts or events
arising after the effective date of the registration statement (or the most recent post-effective amendment thereof) which, individually
or in the aggregate, represent a fundamental change in the information set forth in the registration statement; and</P>

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

<P STYLE="font: 10pt Times New Roman, Times, Serif; margin: 0; text-align: justify">(iii) To include any material information with respect
to the plan of distribution not previously disclosed in the registration statement or any material change to such information in the registration
statement;</P>

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

<P STYLE="font: 10pt Times New Roman, Times, Serif; margin: 0; text-align: justify"><I>provided, however,</I>&nbsp;that paragraphs (1)(i)
and (1)(ii) do not apply if the information required to be included in a post-effective amendment by those paragraphs is contained in
reports filed with or furnished to the Commission by the registrant pursuant to Section 13 or Section 15(d) of the Exchange Act that are
incorporated by reference in the registration statement.</P>

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

<P STYLE="font: 10pt Times New Roman, Times, Serif; margin: 0; text-align: justify">(2) That, for the purpose of determining any liability
under the Securities Act, each such post-effective amendment shall be deemed to be a new registration statement relating to the securities
offered therein, and the offering of such securities at that time shall be deemed to be the initial&nbsp;<I>bona fide</I>&nbsp;offering
thereof.</P>

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

<P STYLE="font: 10pt Times New Roman, Times, Serif; margin: 0; text-align: justify">(3) To remove from registration by means of a post-effective
amendment any of the securities being registered which remain unsold at the termination of the offering.</P>

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

<P STYLE="font: 10pt Times New Roman, Times, Serif; margin: 0; text-align: justify">2.&nbsp;<I>Item 512(b) of Regulation S-K</I>. The
undersigned registrant hereby undertakes that, for purposes of determining any liability under the Securities Act, each filing of the
registrant&rsquo;s annual report pursuant to Section 13(a) or Section 15(d) of the Exchange Act that is incorporated by reference in the
registration statement shall be deemed to be a new registration statement relating to the securities offered therein, and the offering
of such securities at that time shall be deemed to be the initial bona fide offering thereof.</p>

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


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

<P STYLE="font: 10pt Times New Roman, Times, Serif; margin: 0; text-align: justify">3.&nbsp;<I>Item 512(h) of Regulation S-K</I>. Insofar
as indemnification for liabilities arising under the Securities Act may be permitted to directors, officers and controlling persons of
the registrant pursuant to the foregoing provisions, or otherwise, the registrant has been advised that in the opinion of the Commission
such indemnification is against public policy as expressed in the Securities Act and is, therefore, unenforceable. In the event that a
claim for indemnification against such liabilities (other than the payment by the registrant of expenses incurred or paid by a director,
officer or controlling person of the registrant in the successful defense of any action, suit or proceeding) is asserted by such director,
officer or controlling person in connection with the securities being registered, the registrant will, unless in the opinion of its counsel
the matter has been settled by controlling precedent, submit to a court of appropriate jurisdiction the question whether such indemnification
by it is against public policy as expressed in the Securities Act and will be governed by the final adjudication of such issue.</P>

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

<P STYLE="font: 12pt Times New Roman, Times, Serif; margin: 0">&nbsp;</P>


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

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

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

<P STYLE="font: 10pt Times New Roman, Times, Serif; margin: 0; text-align: justify; text-indent: 0.25in">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&nbsp;Form&nbsp;S-8&nbsp;and has duly caused this Registration Statement to be signed on its behalf by the undersigned,
thereunto duly authorized, in the City of Miami, State of Florida, on this 1st day of May, 2024.</P>

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

<TABLE CELLSPACING="0" CELLPADDING="0" STYLE="width: 100%; border-collapse: collapse; font-size: 12pt">
  <TR>
    <TD STYLE="vertical-align: top; width: 59%"><b>&nbsp;</b></TD>
    <TD STYLE="vertical-align: bottom; width: 5%"><b>&nbsp;</b></TD>
    <TD STYLE="vertical-align: top; width: 36%"><font style="font-size: 10pt"><b>SUMMIT THERAPEUTICS INC.</b></font></TD></TR>
  <TR>
    <TD>&nbsp;</TD>
    <TD COLSPAN="2">&nbsp;</TD></TR>
  <TR>
    <TD STYLE="vertical-align: top">&nbsp;</TD>
    <TD STYLE="vertical-align: bottom"><FONT STYLE="font-size: 10pt">By:</FONT></TD>
    <TD STYLE="vertical-align: top">
    <P STYLE="font: 10pt Times New Roman, Times, Serif; margin: 0; border-bottom: black 0.75pt solid">/s/ Robert W. Duggan</P></TD></TR>
  <TR>
    <TD STYLE="vertical-align: top">&nbsp;</TD>
    <TD STYLE="vertical-align: bottom">&nbsp;</TD>
    <TD STYLE="vertical-align: top"><FONT STYLE="font-size: 10pt">Robert W. Duggan</FONT></TD></TR>
  <TR>
    <TD STYLE="vertical-align: top">&nbsp;</TD>
    <TD STYLE="vertical-align: bottom">&nbsp;</TD>
    <TD STYLE="vertical-align: top"><FONT STYLE="font-size: 10pt">Chief Executive Officer; Executive Chairman</FONT></TD></TR>
  </TABLE>
<P STYLE="font: 10pt Times New Roman, Times, Serif; margin: 0; text-align: center"><B>&nbsp;</B></P>

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


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    <DIV STYLE="break-before: page; margin-top: 6pt; margin-bottom: 6pt"><P STYLE="margin: 0pt">&nbsp;</P></DIV>
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<P STYLE="font: 10pt Times New Roman, Times, Serif; margin: 0"><B>&nbsp;</B></P>

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

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

<P STYLE="font: 10pt Times New Roman, Times, Serif; margin: 0; text-align: justify"><a name="POA"></a>We, the undersigned officers and directors of Summit
Therapeutics Inc., hereby severally constitute and appoint Robert W. Duggan, Mahkam Zanganeh and Manmeet Soni, and each of them singly,
our true and lawful attorneys with full power to them, and each of them singly, to sign for us and in our names in the capacities indicated
below, the registration statement on Form S-8 filed herewith and any and all subsequent amendments to said registration statement, and
generally to do all such things in our names and on our behalf in our capacities as officers and directors to enable Summit Therapeutics
Inc. to comply with the provisions of the Securities Act of 1933, as amended, and all requirements of the Securities and Exchange Commission,
hereby ratifying and confirming our signatures as they may be signed by our said attorneys, or any of them, to said registration statement
and any and all amendments thereto.</P>

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

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

<table cellspacing="0" cellpadding="0" style="width: 100%; border-collapse: collapse; font-size: 12pt">
  <TR>
    <td style="vertical-align: bottom; text-align: center; width: 18%"><font style="font-size: 10pt"><b>Name</b></font></TD>
    <td style="width: 2%"><b>&nbsp;</b></TD>
    <td style="vertical-align: bottom; text-align: center; width: 59%"><font style="font-size: 10pt"><b>Title</b></font></TD>
    <td style="width: 2%"><b>&nbsp;</b></TD>
    <td style="border-bottom: Black 1pt solid; vertical-align: bottom; text-align: center; width: 18%"><font style="font-size: 10pt"><b>Date</b></font></TD>
    <td style="width: 1%"><b>&nbsp;</b></TD></TR>
  <TR>
    <td style="border-top: black 1pt solid; vertical-align: bottom; text-align: center"><FONT STYLE="font-size: 10pt">/s/ Robert W. Duggan</FONT></TD>
    <td>&nbsp;</TD>
    <td style="border-top: black 1pt solid; vertical-align: bottom"><FONT STYLE="font-size: 10pt">Chief Executive Officer and Executive Chairman (<I>Principal Executive Officer</I>)</FONT></TD>
    <td>&nbsp;</TD>
    <td style="vertical-align: bottom; text-align: right"><FONT STYLE="font-size: 10pt">April 30, 2024</FONT></TD>
    <td>&nbsp;</TD></TR>
  <TR>
    <td style="border-top: black 1pt solid; vertical-align: bottom; text-align: center"><FONT STYLE="font-size: 10pt">Robert W. Duggan</FONT></TD>
    <td>&nbsp;</TD>
    <td>&nbsp;</TD>
    <td>&nbsp;</TD>
    <td>&nbsp;</TD>
    <td>&nbsp;</TD></TR>
  <TR>
    <td style="vertical-align: bottom; text-align: center">&nbsp;</TD>
    <td>&nbsp;</TD>
    <td>&nbsp;</TD>
    <td>&nbsp;</TD>
    <td>&nbsp;</TD>
    <td>&nbsp;</TD></TR>
  <TR>
    <td style="vertical-align: bottom; text-align: center"><FONT STYLE="font-size: 10pt">/s/ Mahkam Zanganeh</FONT></TD>
    <td>&nbsp;</TD>
    <td style="vertical-align: bottom">
    <P STYLE="font: 10pt Times New Roman, Times, Serif; margin: 0">Chief Executive Officer, President and Director</P>
    <P STYLE="font: 10pt Times New Roman, Times, Serif; margin: 0">(<I>Principal Executive Officer</I>)</P></TD>
    <td>&nbsp;</TD>
    <td style="vertical-align: bottom; text-align: right"><FONT STYLE="font-size: 10pt">April 30, 2024</FONT></TD>
    <td>&nbsp;</TD></TR>
  <TR>
    <td style="border-top: black 1pt solid; vertical-align: bottom; text-align: center"><FONT STYLE="font-size: 10pt">Dr. Mahkam Zanganeh</FONT></TD>
    <td>&nbsp;</TD>
    <td>&nbsp;</TD>
    <td>&nbsp;</TD>
    <td>&nbsp;</TD>
    <td>&nbsp;</TD></TR>
  <TR>
    <td>&nbsp;</TD>
    <td>&nbsp;</TD>
    <td>&nbsp;</TD>
    <td>&nbsp;</TD>
    <td>&nbsp;</TD>
    <td>&nbsp;</TD></TR>
  <TR>
    <td style="vertical-align: bottom; text-align: center"><FONT STYLE="font-size: 10pt">/s/ Manmeet Soni</FONT></TD>
    <td>&nbsp;</TD>
    <td style="vertical-align: bottom"><FONT STYLE="font-size: 10pt">Chief Operating Officer, Chief Financial Officer and Director <I>(Principal Financial Officer)</I></FONT></TD>
    <td>&nbsp;</TD>
    <td style="vertical-align: bottom; text-align: right"><FONT STYLE="font-size: 10pt">April 30, 2024</FONT></TD>
    <td>&nbsp;</TD></TR>
  <TR>
    <td style="border-top: black 1pt solid; vertical-align: bottom; text-align: center"><FONT STYLE="font-size: 10pt">Manmeet Soni</FONT></TD>
    <td>&nbsp;</TD>
    <td>&nbsp;</TD>
    <td>&nbsp;</TD>
    <td>&nbsp;</TD>
    <td>&nbsp;</TD></TR>
  <TR>
    <td>&nbsp;</TD>
    <td>&nbsp;</TD>
    <td>&nbsp;</TD>
    <td>&nbsp;</TD>
    <td>&nbsp;</TD>
    <td>&nbsp;</TD></TR>
  <TR>
    <td style="vertical-align: bottom; text-align: center"><FONT STYLE="font-size: 10pt">/s/ Bhaskar Anand</FONT></TD>
    <td style="text-align: center">&nbsp;</TD>
    <td style="vertical-align: bottom"><FONT STYLE="font-size: 10pt">Chief Accounting Officer, Head of Finance <I>(Principal Accounting Officer)</I></FONT></TD>
    <td>&nbsp;</TD>
    <td style="vertical-align: bottom; text-align: right"><FONT STYLE="font-size: 10pt">April 30, 2024</FONT></TD>
    <td>&nbsp;</TD></TR>
  <TR>
    <td style="border-top: black 1pt solid; vertical-align: bottom; text-align: center"><FONT STYLE="font-size: 10pt">Bhaskar Anand</FONT></TD>
    <td style="text-align: center">&nbsp;</TD>
    <td>&nbsp;</TD>
    <td>&nbsp;</TD>
    <td>&nbsp;</TD>
    <td>&nbsp;</TD></TR>
  <TR>
    <td>&nbsp;</TD>
    <td>&nbsp;</TD>
    <td>&nbsp;</TD>
    <td>&nbsp;</TD>
    <td>&nbsp;</TD>
    <td>&nbsp;</TD></TR>
  <TR>
    <td style="vertical-align: bottom; text-align: center"><FONT STYLE="font-size: 10pt">/s/ Robert F. Booth</FONT></TD>
    <td>&nbsp;</TD>
    <td style="vertical-align: bottom"><FONT STYLE="font-size: 10pt">Director</FONT></TD>
    <td>&nbsp;</TD>
    <td style="vertical-align: bottom; text-align: right"><FONT STYLE="font-size: 10pt">April 29, 2024</FONT></TD>
    <td>&nbsp;</TD></TR>
  <TR>
    <td style="border-top: black 1pt solid; vertical-align: bottom; text-align: center"><FONT STYLE="font-size: 10pt">Dr. Robert F. Booth</FONT></TD>
    <td>&nbsp;</TD>
    <td>&nbsp;</TD>
    <td>&nbsp;</TD>
    <td>&nbsp;</TD>
    <td>&nbsp;</TD></TR>
  <TR>
    <td>&nbsp;</TD>
    <td>&nbsp;</TD>
    <td>&nbsp;</TD>
    <td>&nbsp;</TD>
    <td>&nbsp;</TD>
    <td>&nbsp;</TD></TR>
  <TR>
    <td style="vertical-align: bottom; text-align: center"><FONT STYLE="font-size: 10pt">/s/ Alessandra Cesano</FONT></TD>
    <td>&nbsp;</TD>
    <td style="vertical-align: bottom"><FONT STYLE="font-size: 10pt">Director</FONT></TD>
    <td>&nbsp;</TD>
    <td style="vertical-align: bottom; text-align: right"><FONT STYLE="font-size: 10pt">April 29, 2024</FONT></TD>
    <td>&nbsp;</TD></TR>
  <TR>
    <td style="border-top: black 1pt solid; vertical-align: bottom; text-align: center"><FONT STYLE="font-size: 10pt">Dr. Alessandra Cesano</FONT></TD>
    <td>&nbsp;</TD>
    <td>&nbsp;</TD>
    <td>&nbsp;</TD>
    <td>&nbsp;</TD>
    <td>&nbsp;</TD></TR>
  <TR>
    <td>&nbsp;</TD>
    <td>&nbsp;</TD>
    <td>&nbsp;</TD>
    <td>&nbsp;</TD>
    <td>&nbsp;</TD>
    <td>&nbsp;</TD></TR>
  <TR>
    <td style="vertical-align: bottom; text-align: center"><FONT STYLE="font-size: 10pt">/s/ Kenneth Clark</FONT></TD>
    <td>&nbsp;</TD>
    <td style="vertical-align: bottom"><FONT STYLE="font-size: 10pt">Director</FONT></TD>
    <td>&nbsp;</TD>
    <td style="vertical-align: bottom; text-align: right"><FONT STYLE="font-size: 10pt">April 29, 2024</FONT></TD>
    <td>&nbsp;</TD></TR>
  <TR>
    <td style="border-top: black 1pt solid; vertical-align: bottom; text-align: center"><FONT STYLE="font-size: 10pt">Kenneth Clark</FONT></TD>
    <td>&nbsp;</TD>
    <td>&nbsp;</TD>
    <td>&nbsp;</TD>
    <td>&nbsp;</TD>
    <td>&nbsp;</TD></TR>
  <TR>
    <td>&nbsp;</TD>
    <td>&nbsp;</TD>
    <td>&nbsp;</TD>
    <td>&nbsp;</TD>
    <td>&nbsp;</TD>
    <td>&nbsp;</TD></TR>
  <TR>
    <td style="vertical-align: bottom; text-align: center"><FONT STYLE="font-size: 10pt">/s/ Ujwala Mahatme</FONT></TD>
    <td>&nbsp;</TD>
    <td style="vertical-align: bottom"><FONT STYLE="font-size: 10pt">Director</FONT></TD>
    <td>&nbsp;</TD>
    <td style="vertical-align: bottom; text-align: right"><FONT STYLE="font-size: 10pt">April 30, 2024</FONT></TD>
    <td>&nbsp;</TD></TR>
  <TR>
    <td style="border-top: black 1pt solid; vertical-align: bottom; text-align: center"><FONT STYLE="font-size: 10pt">Ujwala Mahatme</FONT></TD>
    <td>&nbsp;</TD>
    <td>&nbsp;</TD>
    <td>&nbsp;</TD>
    <td>&nbsp;</TD>
    <td>&nbsp;</TD></TR>
  <TR>
    <td>&nbsp;</TD>
    <td>&nbsp;</TD>
    <td>&nbsp;</TD>
    <td>&nbsp;</TD>
    <td>&nbsp;</TD>
    <td>&nbsp;</TD></TR>
  <TR>
    <td style="border-bottom: Black 1pt solid; vertical-align: bottom; text-align: center"><FONT STYLE="font-size: 10pt">/s/ Yu Xia</FONT></TD>
    <td>&nbsp;</TD>
    <td style="vertical-align: bottom"><FONT STYLE="font-size: 10pt">Director</FONT></TD>
    <td>&nbsp;</TD>
    <td style="vertical-align: bottom; text-align: right"><FONT STYLE="font-size: 10pt">May 1, 2024</FONT></TD>
    <td>&nbsp;</TD></TR>
  <TR>
    <td style="vertical-align: bottom; text-align: center"><FONT STYLE="font-size: 10pt">Dr. Yu Xia</FONT></TD>
    <td>&nbsp;</TD>
    <td>&nbsp;</TD>
    <td>&nbsp;</TD>
    <td>&nbsp;</TD>
    <td>&nbsp;</TD></TR>
  <TR>
    <td style="vertical-align: bottom; text-align: center">&nbsp;</TD>
    <td>&nbsp;</TD>
    <td>&nbsp;</TD>
    <td>&nbsp;</TD>
    <td>&nbsp;</TD>
    <td>&nbsp;</TD></TR>
  <TR>
    <td style="vertical-align: bottom; text-align: center"><FONT STYLE="font-size: 10pt">/s/ Mostafa Ronaghi</FONT></TD>
    <td>&nbsp;</TD>
    <td style="vertical-align: bottom"><FONT STYLE="font-size: 10pt">Director</FONT></TD>
    <td>&nbsp;</TD>
    <td style="vertical-align: bottom; text-align: right"><FONT STYLE="font-size: 10pt">April 30, 2024</FONT></TD>
    <td>&nbsp;</TD></TR>
  <TR>
    <td style="border-top: black 1pt solid; vertical-align: bottom; text-align: center"><FONT STYLE="font-size: 10pt">Dr. Mostafa Ronaghi</FONT></TD>
    <td>&nbsp;</TD>
    <td>&nbsp;</TD>
    <td>&nbsp;</TD>
    <td>&nbsp;</TD>
    <td>&nbsp;</TD></TR>
  </TABLE>
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{"company-data": {"conformed-name": "Summit Therapeutics Inc.", "cik": "0001599298", "assigned-sic": "2834", "organization-name": "03 Life Sciences", "irs-number": "000000000", "state-of-incorporation": "DE", "fiscal-year-end": "1231"}, "filing-values": {"form-type": "S-8", "act": "33", "file-number": "333-279024", "film-number": "24900233"}, "business-address": {"street1": "2882 SAND HILL ROAD", "street2": "SUITE 106", "city": "MENLO PARK", "state": "CA", "zip": "94025", "phone": "650-460-8308"}, "mail-address": {"street1": "2882 SAND HILL ROAD", "street2": "SUITE 106", "city": "MENLO PARK", "state": "CA", "zip": "94025"}, "former-company": [{"former-conformed-name": "Summit Therapeutics plc", "date-changed": "20150219"}, {"former-conformed-name": "Summit Corp plc", "date-changed": "20140205"}]}
As filed with the Securities and Exchange Commission
on May 1, 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
SUMMIT THERAPEUTICS INC.
(Exact Name of Registrant as Specified in Its Charter)
Delaware
37-1979717
(State or Other Jurisdiction of
Incorporation or Organization)
(I.R.S. Employer
Identification No.)
601 Brickell Key Drive, Suite 1000
Miami, FL
33131
(Address of Principal Executive Offices)
(Zip Code)
2020 Stock Incentive Plan
2020 Employee Stock Purchase Plan
(Full Title of the Plan)
Robert Duggan
Chief Executive Officer
Summit Therapeutics Inc.
601 Brickell Key Drive, Suite 1000
Miami, FL 33131
(650) 460-8308
Mahkam Zanganeh
Chief Executive Officer
Summit Therapeutics Inc.
601 Brickell Key Drive, Suite 1000
Miami, FL 33131
(650) 460-8308
(Name, Address and Telephone Number, Including Area
Code, of Agent For Service)
Copies to:
Adam Finerman, Esq.
Baker & Hostetler LLP
45 Rockefeller Plaza
New York, NY 10111
Tel: (212) 589-4233
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 is filed for
the purposes of registering 90,800,000 and 825,751 additional shares of common stock, par value $0.01 per share ("Common Stock")
of Summit Therapeutics Inc. (the "Registrant") that may be issued pursuant to the Summit Therapeutics Inc. 2020 Stock Incentive
Plan (the "2020 Plan") and the Summit Therapeutics Inc. 2020 Employee Stock Purchase Plan ("2020 ESPP"), respectively.
The number of shares of Common Stock reserved and
available for issuance under the 2020 Plan is subject to an automatic annual increase on each January 1, beginning with the fiscal year
ending December 31, 2021 and continuing for each fiscal year until, and including, the fiscal year ending December 31, 2030, by an amount
equal to the least of (i) 6,400,000 shares of Common Stock, (ii)
4% of the outstanding shares on
such date and (iii) an amount determined by the board of directors of the Registrant (the "Board").
Accordingly, on (i) January 1, 2023, the number of
shares of Common Stock reserved and available for issuance under the 2020 Plan increased by 6,400,000, and (ii) January 1, 2024, the number
of shares of Common Stock reserved and available for issuance under the 2020 Plan increased by 6,400,000. In addition, the 2020 Plan has
been amended twice with the approval of the Registrant's stockholders to increase the number of shares of Common Stock reserved and
available for issuance thereunder: (i) by 8,000,000 shares pursuant to the approval of stockholders at a Special Meeting of stockholders
held on July 27, 2022 and (ii) by 70,000,000 shares pursuant to the approval of stockholders at a Special Meeting of Stockholders held
on October 12, 2023. This Registration Statement registers both (i) the additional 12,800,000 shares of Common Stock reserved and available
for issuance in accordance with the automatic annual increase provided for under the terms of the 2020 Plan and (ii) the additional 78,000,000
shares of Common Stock reserved and available for issuance pursuant to amendments to the 2020 Plan previously approved by stockholders.
The additional shares are of the same class as other securities relating to the 2020 Plan for which the Registrant's registration
statements on Form S-8, Registration No. 333-249313 and Registration No. 333-264163, filed on October 5, 2020 and April 6, 2022 respectively,
are effective.
The number of shares of Common Stock reserved and
available for issuance under the 2020 ESPP is subject to an automatic annual increase
on each fiscal
year commencing January 1, 2021 and continuing for each fiscal year until, and including the fiscal year commencing on, January 1, 2030
equal to the least of (i) 1,600,000 shares of common stock, (ii) 1% of the common shares outstanding on such date and (iii)
an amount as determined by the Board.
Effective (i) January 1, 2021, the Board determined
to increase the number of shares of Common Stock reserved and available for issuance under the 2020 ESPP by 825,751, (ii) January 1, 2022,
the Board determined to increase the number of shares of Common Stock reserved and available for issuance under the 2020 ESPP by 980,000
(which shares have been previously registered), and (iii) January 1, 2023 and 2024, the Board determined that there would be no increase
in the number of shares of Common Stock reserved and available for issuance under the 2020 ESPP. This Registration Statement registers
the additional 825,751 shares of Common Stock reserved and available for issuance in accordance with the automatic annual increase provided
for under the terms of the 2020 ESPP. The shares of Common Stock shall be of the same class as other securities relating to the 2020 ESPP
for which the Registrant's registration statement on Form S-8, Registration No. 333-264163, filed on April 6, 2022 is effective.
PART I
INFORMATION REQUIRED IN THE SECTION 10(a) PROSPECTUS
Item 1. Plan Information.
The information required by Item 1 is included in
documents sent or given to participants in the plans covered by this registration statement pursuant to Rule 428(b)(1) of the Securities
Act.
Item 2. Registrant Information and Employee Plan
Annual Information.
The written statement required by Item 2 is included
in documents sent or given to participants in the plans covered by this registration statement pursuant to Rule 428(b)(1) of the Securities
Act.
PART II
INFORMATION REQUIRED IN THE REGISTRATION STATEMENT
Item 3. Incorporation of Documents by Reference.
The registrant is subject to the informational and
reporting requirements of Sections 13(a), 14, and 15(d) of the Exchange Act, and in accordance therewith files reports, proxy statements
and other information with the Securities and Exchange Commission (the "Commission"). The following documents, which have
been filed with the Commission, are incorporated in this registration statement by reference:
(a)
The registrant's Annual Report on Form 10-K for the fiscal year ended December 31, 2023, filed on February 20, 2024.
(b)
The registrant's Quarterly Report on Form 10-Q
    for the fiscal quarter ended March 31, 2024, filed on May 1, 2024.
(c)
The registrant's Current Reports on Form 8-K filed on January 3, 2024, February 8, 2024, March 5, 2024, March 22, 2024, April 3, 2024, and April 11, 2024.
(d)
The description of the securities contained in the registrant's Current Report on Form 8-K dated September 18, 2020, including any amendment or report filed for the purposes of updating such description.
All documents subsequently filed by the registrant
pursuant to Sections 13(a), 13(c), 14 and 15(d) of the Exchange Act, prior to the filing of a post-effective amendment to this registration
statement which indicates that all securities offered hereby have been sold or which deregisters all securities then remaining unsold,
shall be deemed to be incorporated by reference in this registration statement and to be part hereof from the date of the filing of such
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 the purposes of this registration statement to the extent that a statement contained herein or in any other subsequently
filed document which also is or is deemed to be incorporated by reference herein modifies or supersedes such statement. Any statement
so modified or superseded shall not be deemed, except as so modified or superseded, to constitute a part of this registration statement.
Item 4. Description of Securities.
Not applicable.
Item 5. Interests of Named Experts and Counsel.
Not applicable.
Item 6. Indemnification of Directors and Officers.
Section 102 of the Delaware General Corporation Law
permits a corporation to eliminate the personal liability of directors of a corporation to the corporation or its stockholders for monetary
damages for a breach of fiduciary duty as a director, except where the director breached his or her duty of loyalty, failed to act in
good faith, engaged in intentional misconduct or knowingly violated a law, authorized the payment of a dividend or approved a stock repurchase
in violation of Delaware corporate law or obtained an improper personal benefit. The registrant's certificate of incorporation provides
that none of its directors shall be personally liable to the registrant or its stockholders for monetary damages for any breach of fiduciary
duty as director, notwithstanding any provision of law imposing such liability, except to the extent that the Delaware General Corporation
Law prohibits the elimination or limitation of liability of directors for breaches of fiduciary duty.
Section 145 of the Delaware General Corporation Law
provides that a corporation has the power to indemnify a director, officer, employee or agent of the corporation and certain other persons
serving at the request of the corporation in related capacities against expenses (including attorneys' fees), judgments, fines and
amounts paid in settlements actually and reasonably incurred by the
person in connection with an action, suit or proceeding to which he or she is or is threatened to be made a party by reason of such position,
if such person acted in good faith and in a manner he or she reasonably believed to be in or not opposed to the best interests of the
corporation and, in any criminal action or proceeding, had no reasonable cause to believe his or her conduct was unlawful, except that,
in the case of actions brought by or in the right of the corporation, no indemnification shall be made with respect to any claim, issue
or matter as to which such person shall have been adjudged to be liable to the corporation unless and only to the extent that the Court
of Chancery or other adjudicating court determines that, despite the adjudication of liability but in view of all of the circumstances
of the case, such person is fairly and reasonably entitled to indemnity for such expenses which the Court of Chancery or such other court
shall deem proper.
The registrant's certificate of incorporation
provides that the registrant will indemnify each person who was or is a party or threatened to be made a party to or is involved in any
threatened, pending or completed action, suit or proceeding
,
whether civil, criminal, administrative or investigative (other
than an action by or in the right of the registrant) by reason of the fact that he or she is or was a director or officer of the registrant,
or is or was serving at the registrant's request as a director or officer of another corporation, partnership, joint venture, trust
or other enterprise to the fullest extent permitted by the Delaware General Corporation Law. The registrant's certificate of incorporation
provides that any reasonable, documented, out-pocket expenses must be advanced to these indemnitees under certain circumstances.
The indemnification provisions contained in the registrant's
certificate of incorporation are not exclusive. In addition, the registrant has entered into indemnification agreements with each of its
directors and executive officers. Each indemnification agreement provides that the registrant will indemnify the director or executive
officer to the fullest extent permitted by law for claims arising in his or her capacity as a director or executive officer, provided
that he or she acted in good faith and in a manner that he or she reasonably believed to be in, or not opposed to, the registrant's
best interests and, with respect to any criminal proceeding, had no reasonable cause to believe that his or her conduct was unlawful.
In the event that the registrant does not assume the defense of a claim against a director or executive officer, the registrant is required
to advance his or her expenses in connection with his or her defense, provided that he or she undertakes to repay all amounts advanced
if it is ultimately determined that he or she is not entitled to be indemnified by the registrant.
In addition, the registrant maintains standard policies
of insurance under which coverage is provided to the registrant's directors and officers against losses arising from claims made
by reason of breach of duty or other wrongful act, and to the registrant with respect to payments which may be made by the registrant
to such directors and officers pursuant to the above indemnification provisions or otherwise as a matter of law.
Item 7. Exemption from Registration Claimed.
Not applicable.
Item 8. Exhibits.
The following exhibits are incorporated herein by
reference:
Number
Description
4.1
Restated Certificate of Incorporation of the registrant (incorporated by reference to Exhibit 3.1 to the registrant's Current Report on Form 8-K (File No. 001-36866), filed with the Securities and Exchange Commission on September 18, 2020).
4.2
Amendment to Restated Certificate of Incorporation of Summit Therapeutics Inc., as filed with the Delaware Secretary of State on July 27, 2022 (incorporated by reference to Exhibit 3.1 of Form 8-K filed by the Registrant on July 29, 2022, File No. 001-36866).
4.3
Amendment No. 2 to Restated Certificate of Incorporation, dated January 19, 2023 (incorporated by reference to Exhibit 5.1 of Form 8-K filed by the Registrant on January 20, 2023, File No. 001-36866).
4.4
Amended and Restated Bylaws of the registrant (incorporated by reference to Exhibit 3.2 to the registrant's Current Report on Form 8-K (File No. 001-36866), filed with the Securities and Exchange Commission on September 18, 2020).
5.1
Opinion of BakerHostetler LLP, counsel to the registrant.
23.1
Consent of BakerHostetler LLP (included in Exhibit 5.1).
23.2
Consent of PricewaterhouseCoopers LLP, independent registered public accounting firm for the registrant.
24
Powers of attorney (included on the signature pages of this registration statement).
99.1
2020 Stock Incentive Plan (as amended and restated as of October 12, 2023).
99.2
2020 Employee Stock Purchase Plan (incorporated by reference to Exhibit 10.3 to the Registrant's Current Report on Form 8-K (File No. 001-36866), filed with the Securities and Exchange Commission on September 18, 2020).
107
Filing Fee Table.
Item 9. Undertakings.
1.
Item 512(a) of Regulation S-K
. The
undersigned registrant hereby undertakes:
(1) To file, during any period in which offers
or sales are being made, a post-effective amendment to this registration statement:
(i) To include any prospectus required by Section
10(a)(3) of the Securities Act;
(ii) To reflect in the prospectus any facts or events
arising after the effective date of the registration statement (or the most recent post-effective amendment thereof) which, individually
or in the aggregate, represent a fundamental change in the information set forth in the registration statement; and
(iii) To include any material information with respect
to the plan of distribution not previously disclosed in the registration statement or any material change to such information in the registration
statement;
provided, however,
that paragraphs (1)(i)
and (1)(ii) do not apply if the information required to be included in a post-effective amendment by those paragraphs is contained in
reports filed with or furnished to the Commission by the registrant pursuant to Section 13 or Section 15(d) of the Exchange Act that are
incorporated by reference in the registration statement.
(2) That, for the purpose of determining any liability
under the Securities Act, each such post-effective amendment shall be deemed to be a new registration statement relating to the securities
offered therein, and the offering of such securities at that time shall be deemed to be the initial
bona fide
offering
thereof.
(3) To remove from registration by means of a post-effective
amendment any of the securities being registered which remain unsold at the termination of the offering.
2.
Item 512(b) of Regulation S-K
. The
undersigned registrant hereby undertakes that, for purposes of determining any liability under the Securities Act, each filing of the
registrant's annual report pursuant to Section 13(a) or Section 15(d) of the Exchange Act that is incorporated by reference in the
registration statement shall be deemed to be a new registration statement relating to the securities offered therein, and the offering
of such securities at that time shall be deemed to be the initial bona fide offering thereof.
3.
Item 512(h) of Regulation S-K
. Insofar
as indemnification for liabilities arising under the Securities Act may be permitted to directors, officers and controlling persons of
the registrant pursuant to the foregoing provisions, or otherwise, the registrant has been advised that in the opinion of the Commission
such indemnification is against public policy as expressed in the Securities Act and is, therefore, unenforceable. In the event that a
claim for indemnification against such liabilities (other than the payment by the registrant of expenses incurred or paid by a director,
officer or controlling person of the registrant in the successful defense of any action, suit or proceeding) is asserted by such director,
officer or controlling person in connection with the securities being registered, the registrant will, unless in the opinion of its counsel
the matter has been settled by controlling precedent, submit to a court of appropriate jurisdiction the question whether such indemnification
by it is against public policy as expressed in the Securities Act and will be governed by the final adjudication of such issue.
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 Miami, State of Florida, on this 1st day of May, 2024.
SUMMIT THERAPEUTICS INC.
By:
/s/ Robert W. Duggan
Robert W. Duggan
Chief Executive Officer; Executive Chairman
POWER OF ATTORNEY AND SIGNATURES
We, the undersigned officers and directors of Summit
Therapeutics Inc., hereby severally constitute and appoint Robert W. Duggan, Mahkam Zanganeh and Manmeet Soni, and each of them singly,
our true and lawful attorneys with full power to them, and each of them singly, to sign for us and in our names in the capacities indicated
below, the registration statement on Form S-8 filed herewith and any and all subsequent amendments to said registration statement, and
generally to do all such things in our names and on our behalf in our capacities as officers and directors to enable Summit Therapeutics
Inc. to comply with the provisions of the Securities Act of 1933, as amended, and all requirements of the Securities and Exchange Commission,
hereby ratifying and confirming our signatures as they may be signed by our said attorneys, or any of them, to said registration statement
and any and all amendments thereto.
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.
Name
Title
Date
/s/ Robert W. Duggan
Chief Executive Officer and Executive Chairman (
Principal Executive Officer
)
April 30, 2024
Robert W. Duggan
/s/ Mahkam Zanganeh
Chief Executive Officer, President and Director
(
Principal Executive Officer
)
April 30, 2024
Dr. Mahkam Zanganeh
/s/ Manmeet Soni
Chief Operating Officer, Chief Financial Officer and Director
(Principal Financial Officer)
April 30, 2024
Manmeet Soni
/s/ Bhaskar Anand
Chief Accounting Officer, Head of Finance
(Principal Accounting Officer)
April 30, 2024
Bhaskar Anand
/s/ Robert F. Booth
Director
April 29, 2024
Dr. Robert F. Booth
/s/ Alessandra Cesano
Director
April 29, 2024
Dr. Alessandra Cesano
/s/ Kenneth Clark
Director
April 29, 2024
Kenneth Clark
/s/ Ujwala Mahatme
Director
April 30, 2024
Ujwala Mahatme
/s/ Yu Xia
Director
May 1, 2024
Dr. Yu Xia
/s/ Mostafa Ronaghi
Director
April 30, 2024
Dr. Mostafa Ronaghi