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  <P STYLE="font: 10pt Times New Roman; margin: 0pt 0; text-align: center">As filed with the Securities and Exchange Commission on
  September 14, 2020</P>
  
  <P STYLE="font: 10pt Times New Roman; margin: 0pt 0">&nbsp;</P>
  
  <P STYLE="font: 10pt Times New Roman; margin: 0pt 0; text-align: right; background-color: white"><B>Registration No. 333-</B></P>
  
  <!-- Field: Rule-Page --><DIV STYLE="margin-top: 12pt; margin-bottom: 3pt; width: 100%"><DIV STYLE="font-size: 1pt; border-top: Black 2pt solid; border-bottom: Black 1pt solid">&nbsp;</DIV></DIV><!-- Field: /Rule-Page -->
  
  <P STYLE="font: 10pt Times New Roman; margin: 0pt 0"></P>
  
  <P STYLE="font: 14pt Times New Roman; margin: 0pt 0; text-align: center; background-color: white"><B>UNITED STATES</B></P>
  
  <P STYLE="font: 14pt Times New Roman; margin: 0pt 0; text-align: center; background-color: white"><B>SECURITIES
  AND EXCHANGE COMMISSION</B></P>
  
  <P STYLE="font: 12pt Times New Roman; margin: 0pt 0; text-align: center; background-color: white"><B>Washington, D.C. 20549</B></P>
  
  <P STYLE="font: 10pt Times New Roman; margin: 0pt 0">&nbsp;</P>
  
  <P STYLE="font: 18pt Times New Roman; margin: 0pt 0; text-align: center; background-color: white"><B>Form S-8</B></P>
  
  <P STYLE="font: 10pt Times New Roman; margin: 0pt 0">&nbsp;</P>
  
  <P STYLE="font: 10pt Times New Roman; margin: 0pt 0; text-align: center; background-color: white"><B>REGISTRATION STATEMENT</B></P>
  
  <P STYLE="font: 10pt Times New Roman; margin: 0pt 0; text-align: center; background-color: white"><B>UNDER THE SECURITIES ACT OF
  1933</B></P>
  
  <P STYLE="font: 10pt Times New Roman; margin: 0pt 0">&nbsp;</P>
  
  <P STYLE="font: 24pt Times New Roman; margin: 0pt 0; text-align: center; background-color: white"><B>Humanigen, Inc.</B></P>
  
  <P STYLE="font: 10pt Times New Roman; margin: 0pt 0; text-align: center; background-color: white">(Exact name of registrant as
  specified in its charter)</P>
  
  <P STYLE="font: 10pt Times New Roman; margin: 0pt 0">&nbsp;</P>
  
  <TABLE CELLSPACING="0" CELLPADDING="0" STYLE="width: 100%; font: 10pt Times New Roman, Times, Serif; border-collapse: collapse">
  <TR STYLE="background-color: white">
      <TD STYLE="white-space: nowrap; vertical-align: top; width: 49%; font-size: 10pt; text-align: center"><FONT STYLE="font-size: 10pt"><B>Delaware</B></FONT></TD>
      <TD STYLE="vertical-align: bottom; width: 2%; font-size: 10pt">&nbsp;</TD>
      <TD STYLE="white-space: nowrap; vertical-align: top; width: 49%; font-size: 10pt; text-align: center"><FONT STYLE="font-size: 10pt"><B>77-0557236</B></FONT></TD></TR>
  <TR STYLE="background-color: white">
      <TD STYLE="white-space: nowrap; vertical-align: top">
          <P STYLE="font: 10pt Times New Roman; margin: 0pt 0; text-align: center">(State or other jurisdiction of</P>
          <P STYLE="font: 10pt Times New Roman; margin: 0pt 0; text-align: center">incorporation or organization)</P></TD>
      <TD STYLE="vertical-align: bottom; font-size: 10pt">&nbsp;</TD>
      <TD STYLE="white-space: nowrap; vertical-align: top">
          <P STYLE="font: 10pt Times New Roman; margin: 0pt 0; text-align: center">(IRS employer identification</P>
          <P STYLE="font: 10pt Times New Roman; margin: 0pt 0; text-align: center">number)</P></TD></TR>
  </TABLE>
  <P STYLE="font: 10pt Times New Roman; margin: 0pt 0">&nbsp;</P>
  
  <P STYLE="font: 10pt Times New Roman; margin: 0pt 0; text-align: center; background-color: white"><B>533 Airport Boulevard, Suite
  400</B></P>
  
  <P STYLE="font: 10pt Times New Roman; margin: 0pt 0; text-align: center; background-color: white"><B>Burlingame, CA 94010</B></P>
  
  <P STYLE="font: 10pt Times New Roman; margin: 0pt 0; text-align: center; background-color: white">(Address of principal executive
  offices)</P>
  
  <P STYLE="font: 10pt Times New Roman; margin: 0pt 0">&nbsp;</P>
  
  <P STYLE="font: 10pt Times New Roman; margin: 0pt 0">&nbsp;</P>
  
  <P STYLE="font: 10pt Times New Roman; margin: 0pt 0; text-align: center; background-color: white"><B>Humanigen, Inc. 2020 Omnibus
  Incentive Compensation Plan</B></P>
  
  <P STYLE="font: 10pt Times New Roman; margin: 0pt 0; text-align: center; background-color: white">(Full title of the Plan)</P>
  
  <P STYLE="font: 10pt Times New Roman; margin: 0pt 0">&nbsp;</P>
  
  <P STYLE="font: 10pt Times New Roman; margin: 0pt 0">&nbsp;</P>
  
  <P STYLE="font: 10pt Times New Roman; margin: 0pt 0; text-align: center; background-color: white"><B>Cameron Durrant, M.D.</B></P>
  
  <P STYLE="font: 10pt Times New Roman; margin: 0pt 0; text-align: center; background-color: white"><B>Chief Executive Officer</B></P>
  
  <P STYLE="font: 10pt Times New Roman; margin: 0pt 0; text-align: center; background-color: white"><B>Humanigen, Inc.</B></P>
  
  <P STYLE="font: 10pt Times New Roman; margin: 0pt 0; text-align: center; background-color: white"><B>533 Airport Boulevard, Suite
  400</B></P>
  
  <P STYLE="font: 10pt Times New Roman; margin: 0pt 0; text-align: center; background-color: white"><B>Burlingame, CA 94010</B></P>
  
  <P STYLE="font: 10pt Times New Roman; margin: 0pt 0; text-align: center; background-color: white"><B>(650) 243-1000</B></P>
  
  <P STYLE="font: 10pt Times New Roman; margin: 0pt 0; text-align: center; background-color: white">(Name, address and telephone
  number of Agent for Service)</P>
  
  <P STYLE="font: 10pt Times New Roman; margin: 0pt 0">&nbsp;</P>
  
  <P STYLE="font: 10pt Times New Roman; margin: 0pt 0; text-align: center; background-color: white"><B><I>Copy to</I>:</B></P>
  
  <P STYLE="font: 10pt Times New Roman; margin: 0pt 0">&nbsp;</P>
  
  <P STYLE="font: 10pt Times New Roman; margin: 0pt 0; text-align: center; background-color: white"><B>Kevin L. Vold, Esq.</B></P>
  
  <P STYLE="font: 10pt Times New Roman; margin: 0pt 0; text-align: center; background-color: white"><B>Polsinelli PC</B></P>
  
  <P STYLE="font: 10pt Times New Roman; margin: 0pt 0; text-align: center; background-color: white"><B>1401 Eye Street, NW, Suite
  800</B></P>
  
  <P STYLE="font: 10pt Times New Roman; margin: 0pt 0; text-align: center; background-color: white"><B>Washington, D.C. 20005</B></P>
  
  <P STYLE="font: 10pt Times New Roman; margin: 0pt 0; text-align: center; background-color: white"><B>(202) 783-3300</B></P>
  
  <P STYLE="font: 10pt Times New Roman; margin: 0pt 0">&nbsp;</P>
  
  <P STYLE="font: 10pt Times New Roman; margin: 0pt 0">&nbsp;</P>
  
  <P STYLE="font: 10pt Times New Roman; margin: 0pt 0; background-color: white">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. (Check one):</P>
  
  <P STYLE="font: 10pt Times New Roman; margin: 0pt 0">&nbsp;</P>
  
  <TABLE CELLSPACING="0" CELLPADDING="0" STYLE="font: 10pt Times New Roman, Times, Serif; width: 95%; border-collapse: collapse; margin-left: 0.5in">
  <TR STYLE="background-color: white">
      <TD STYLE="vertical-align: top; width: 58%; font-size: 10pt"><FONT STYLE="font-size: 10pt">Large accelerated filer <FONT STYLE="font-family: Wingdings">o</FONT></FONT></TD>
      <TD STYLE="vertical-align: bottom; width: 5%; font-size: 10pt">&nbsp;</TD>
      <TD STYLE="vertical-align: top; width: 37%; font-size: 10pt"><FONT STYLE="font-size: 10pt">Accelerated filer <FONT STYLE="font-family: Wingdings">o</FONT></FONT></TD></TR>
  <TR STYLE="background-color: white">
      <TD STYLE="vertical-align: top; font-size: 10pt"><FONT STYLE="font-size: 10pt">Non-accelerated filer <FONT STYLE="font-family: Wingdings">x</FONT></FONT></TD>
      <TD STYLE="vertical-align: bottom; font-size: 10pt">&nbsp;</TD>
      <TD STYLE="vertical-align: top">
          <P STYLE="font: 10pt Times New Roman; margin: 0pt 0">Smaller reporting company <FONT STYLE="font-family: Wingdings">x</FONT></P>
          <P STYLE="font: 10pt Times New Roman; margin: 0pt 0">Emerging growth company <FONT STYLE="font-family: Wingdings">o</FONT></P></TD></TR>
  </TABLE>
  <P STYLE="font: 10pt Times New Roman; margin: 0pt 0">&nbsp;</P>
  
  <P STYLE="font: 10pt Times New Roman; margin: 0pt 0">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. <FONT STYLE="font-family: Wingdings">o</FONT></P>
  
  <P STYLE="font: 10pt Times New Roman; margin: 0pt 0">&nbsp;</P>
  
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  <P STYLE="font: 10pt Times New Roman; margin: 0pt 0"></P>
  
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  <P STYLE="font: 10pt Times New Roman; margin: 0pt 0">&nbsp;</P>
  
  <P STYLE="font: 10pt Times New Roman; margin: 0pt 0; text-align: center"><B>CALCULATION OF REGISTRATION FEE</B></P>
  
  <P STYLE="font: 10pt Times New Roman; margin: 0pt 0">&nbsp;</P>
  
  <TABLE CELLPADDING="0" CELLSPACING="0" STYLE="border-collapse: collapse; width: 100%; font: 10pt Times New Roman, Times, Serif">
  <TR STYLE="vertical-align: bottom">
      <TD STYLE="white-space: nowrap; text-align: center"><P STYLE="font: 10pt Times New Roman; margin: 0pt 0; text-align: center"><B>Title of Securities<BR> to be </B></P> <P STYLE="font: 10pt Times New Roman; margin: 0pt 0; text-align: center"><B>Registered</B></P></TD><TD STYLE="white-space: nowrap; font-weight: bold">&nbsp;</TD>
      <TD STYLE="white-space: nowrap; font-weight: bold; text-align: center"><FONT STYLE="font-size: 10pt"><B>Amount<BR> to be<BR> Registered<SUP>(1)</SUP></B></FONT></TD><TD STYLE="white-space: nowrap; font-weight: bold">&nbsp;</TD>
      <TD STYLE="white-space: nowrap; font-weight: bold; text-align: center"><FONT STYLE="font-size: 10pt"><B>Proposed <BR> Maximum<BR> Offering <BR> Price<BR> per Share<SUP>(2)</SUP></B></FONT></TD><TD STYLE="white-space: nowrap; font-weight: bold">&nbsp;</TD><TD STYLE="white-space: nowrap; font-weight: bold">&nbsp;</TD>
      <TD STYLE="white-space: nowrap; font-weight: bold; text-align: center">Proposed <BR> Maximum<BR> Aggregate<BR> Offering <BR> Price</TD><TD STYLE="white-space: nowrap; font-weight: bold">&nbsp;</TD><TD STYLE="white-space: nowrap; font-weight: bold">&nbsp;</TD>
      <TD STYLE="white-space: nowrap; font-weight: bold; text-align: center">Amount of<BR> Registration<BR> Fee</TD><TD STYLE="white-space: nowrap; font-weight: bold">&nbsp;</TD></TR>
  <TR STYLE="vertical-align: bottom">
      <TD STYLE="white-space: nowrap">&nbsp;</TD><TD>&nbsp;</TD>
      <TD STYLE="white-space: nowrap">&nbsp;</TD><TD>&nbsp;</TD>
      <TD STYLE="white-space: nowrap">&nbsp;</TD><TD>&nbsp;</TD><TD>&nbsp;</TD>
      <TD STYLE="white-space: nowrap">&nbsp;</TD><TD>&nbsp;</TD><TD>&nbsp;</TD>
      <TD STYLE="white-space: nowrap">&nbsp;</TD><TD>&nbsp;</TD></TR>
  <TR STYLE="vertical-align: bottom; background-color: rgb(204,238,255)">
      <TD STYLE="white-space: nowrap; width: 43%">Common stock, $0.001 par value per share</TD><TD STYLE="width: 1%">&nbsp;</TD>
      <TD STYLE="text-align: center; width: 14%">7,000,000</TD><TD STYLE="width: 1%">&nbsp;</TD>
      <TD STYLE="text-align: center; width: 12%">$9.95</TD><TD STYLE="text-align: left; width: 1%">&nbsp;</TD><TD STYLE="width: 1%">&nbsp;</TD>
      <TD STYLE="text-align: center; width: 12%"><FONT STYLE="font-size: 10pt">$69,650,000</FONT></TD><TD STYLE="text-align: left; width: 1%">&nbsp;</TD><TD STYLE="width: 1%">&nbsp;</TD>
      <TD STYLE="text-align: center; width: 12%">$9,040.57</TD><TD STYLE="text-align: left; width: 1%">&nbsp;</TD></TR>
  </TABLE>
  
  
  <P STYLE="font: 10pt Times New Roman; margin: 0pt 0">&nbsp;</P>
  
  <P STYLE="font: 10pt Times New Roman; margin: 0pt 0; text-align: justify">(1) Consists of shares of common stock, $0.001 par value
  per share of the Registrant, or Common Stock, authorized for issuance under the Humanigen, Inc. 2020 Omnibus Incentive Compensation
  Plan and reflects a reverse stock split effective September 11, 2020. Pursuant to Rule 416 of the Securities Act of 1933,
  as amended (the &ldquo;Securities Act&rdquo;), this registration statement also covers any additional shares of common stock which
  become issuable under the above-named plan by reason of any share dividend, share split, recapitalization or any other similar
  transaction without receipt of consideration which results in an increase in the number of shares or common stock outstanding.</P>
  
  <P STYLE="font: 10pt Times New Roman; margin: 0pt 0">&nbsp;</P>
  
  <P STYLE="font: 10pt Times New Roman; margin: 0pt 0; text-align: justify">(2) Estimated pursuant to Rule 457(c) and Rule 457(h)
  of the Securities Act solely for the purpose of calculating the registration fee. The price per share is based on the average of
  the high and low sales price on the OTCQB Venture Market on September 14, 2020.</P>
  
  <P STYLE="font: 10pt Times New Roman; margin: 0pt 0">&nbsp;</P>
  
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  <P STYLE="font: 10pt Times New Roman; margin: 0pt 0">&nbsp;</P>
  
  <P STYLE="font: 10pt Times New Roman; margin: 0pt 0; text-align: center"><B>PART I</B></P>
  
  <P STYLE="font: 10pt Times New Roman; margin: 0pt 0">&nbsp;</P>
  
  <P STYLE="font: 10pt Times New Roman; margin: 0pt 0; text-align: center"><B>INFORMATION REQUIRED IN THE SECTION 10(a) PROSPECTUS</B></P>
  
  <P STYLE="font: 10pt Times New Roman; margin: 0pt 0">&nbsp;</P>
  
  <P STYLE="font: 10pt Times New Roman; margin: 0pt 0; text-align: justify; text-indent: 0.5in">The documents containing the information
  specified in Part I will be sent or given to employees and other individuals participating in the Humanigen, Inc. 2020 Omnibus
  Incentive Compensation Plan (the &ldquo;Plan&rdquo;) in accordance with Rule 428(b)(1) under the Securities Act of 1933, as amended,
  or the Securities Act. Such information is omitted from this Registration Statement in accordance with Rule 428 of the Securities
  Act and the instructions to Form S-8. In accordance with the rules and regulations of the Securities and Exchange Commission, or
  the SEC, and the instructions to Form S-8, such documents are not being filed with the SEC either as part of this Registration
  Statement or as prospectuses or prospectus supplements pursuant to Rule 424.</P>
  
  <P STYLE="font: 10pt Times New Roman; margin: 0pt 0">&nbsp;</P>
  
  <P STYLE="font: 10pt Times New Roman; margin: 0pt 0">&nbsp;</P>
  
  <P STYLE="font: 10pt Times New Roman; margin: 0pt 0; text-align: center"><B>PART II</B></P>
  
  <P STYLE="font: 10pt Times New Roman; margin: 0pt 0">&nbsp;</P>
  
  <P STYLE="font: 10pt Times New Roman; margin: 0pt 0; text-align: center"><B>INFORMATION REQUIRED IN THE REGISTRATION STATEMENT</B></P>
  
  <P STYLE="font: 10pt Times New Roman; margin: 0pt 0">&nbsp;</P>
  
  <TABLE CELLPADDING="0" CELLSPACING="0" STYLE="width: 100%; font: 10pt Times New Roman; margin-top: 0pt; margin-bottom: 0pt"><TR STYLE="vertical-align: top">
  <TD STYLE="width: 0%"></TD><TD STYLE="width: 0.5in"><B>Item 3.</B></TD><TD><B>Incorporation of Documents by Reference.</B></TD></TR></TABLE>
  
  <P STYLE="font: 10pt Times New Roman; margin: 0pt 0">&nbsp;</P>
  
  <P STYLE="font: 10pt Times New Roman; margin: 0pt 0; text-align: justify; text-indent: 0.5in">Humanigen, Inc., or the Company,
  hereby incorporates by reference into this Registration Statement the following documents filed by it with the SEC:</P>
  
  <P STYLE="font: 10pt Times New Roman; margin: 0pt 0">&nbsp;</P>
  
  <TABLE CELLPADDING="0" CELLSPACING="0" WIDTH="100%" STYLE="font: 10pt Times New Roman; margin-top: 0pt; margin-bottom: 0pt"><TR STYLE="vertical-align: top">
  <TD STYLE="width: 0.5in"></TD><TD STYLE="width: 0.5in">(a)</TD><TD>the Company&rsquo;s Annual Report on Form 10-K for the fiscal year ended December 31, 2019, filed with the SEC on March 16,
  2020 (File No. 001-35798); </TD></TR></TABLE>
  
  <P STYLE="font: 10pt Times New Roman; margin: 0pt 0">&nbsp;</P>
  
  <TABLE CELLPADDING="0" CELLSPACING="0" WIDTH="100%" STYLE="font: 10pt Times New Roman; margin-top: 0pt; margin-bottom: 0pt"><TR STYLE="vertical-align: top">
  <TD STYLE="width: 0.5in"></TD><TD STYLE="width: 0.5in">(b)</TD><TD>the Company&rsquo;s Quarterly Report on Form 10-Q for the quarterly period ended March 31, 2020, filed with the SEC on May
  15, 2020, and the Company&rsquo;s Quarterly Report on Form 10-Q for the quarterly period ended June 30, 2020, filed with the SEC
  on August 14, 2020;</TD></TR></TABLE>
  
  <P STYLE="font: 10pt Times New Roman; margin: 0pt 0">&nbsp;</P>
  
  <TABLE CELLPADDING="0" CELLSPACING="0" WIDTH="100%" STYLE="font: 10pt Times New Roman; margin-top: 0pt; margin-bottom: 0pt"><TR STYLE="vertical-align: top">
  <TD STYLE="width: 0.5in"></TD><TD STYLE="width: 0.5in">(c)</TD><TD>our Current Reports on Form 8-K, filed with the SEC on January 31, 2020; March 20, 2020; March 23, 2020; April 6, 2020; April
  29, 2020; May 7, 2020; June 4, 2020; July 6, 2020; July 10, 2020; July 30, 2020; August 3, 2020; September 4, 2020; and September
  11, 2020 (except, with respect to each of the foregoing, for portions of such reports which were deemed to be furnished and not
  filed); and</TD></TR></TABLE>
  
  <P STYLE="font: 10pt Times New Roman; margin: 0pt 0">&nbsp;</P>
  
  <TABLE CELLPADDING="0" CELLSPACING="0" WIDTH="100%" STYLE="font: 10pt Times New Roman; margin-top: 0pt; margin-bottom: 0pt"><TR STYLE="vertical-align: top">
  <TD STYLE="width: 0.5in"></TD><TD STYLE="width: 0.5in">(d)</TD><TD>the description of the Company&rsquo;s common stock contained in Exhibit 4.5 to the Company&rsquo;s Annual Report on Form 10-K
  for the fiscal year ended December 31, 2019, filed with the SEC on March 16, 2020, including any other amendments or reports filed
  for the purpose of updating such description.&nbsp;</TD></TR></TABLE>
  
  <P STYLE="font: 10pt Times New Roman; margin: 0pt 0">&nbsp;</P>
  
  <P STYLE="font: 10pt Times New Roman; margin: 0pt 0; text-align: justify; text-indent: 0.5in">All reports and other documents subsequently
  filed by the Company pursuant to Sections 13(a), 13(c), 14 or 15(d) of the Securities Exchange Act of 1934, as amended, or the
  Exchange Act, prior to the filing of a post-effective amendment that indicates that all securities offered hereby have been sold
  or that deregisters all securities then remaining unsold, shall be deemed to be incorporated by reference herein and to be a part
  hereof from the date of filing of such documents. Unless specifically stated to the contrary, none of the information that the
  Company discloses under Items 2.02 or 7.01 of any Current Report on Form 8-K that the Company has or may from time to time furnish
  to the Commission will be incorporated by reference into, or otherwise be included in, this Registration Statement.</P>
  
  <P STYLE="font: 10pt Times New Roman; margin: 0pt 0">&nbsp;</P>
  
  <P STYLE="font: 10pt Times New Roman; margin: 0pt 0; text-align: justify; text-indent: 0.5in">Any statement contained in a document
  incorporated or deemed to be incorporated by reference herein shall be deemed to be modified or superseded for purposes of this
  Registration Statement to the extent that a statement contained herein or in any 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; margin: 0pt 0">&nbsp;</P>
  
  <P STYLE="font: 10pt Times New Roman; margin: 0pt 0">&nbsp;</P>
  
  <TABLE CELLPADDING="0" CELLSPACING="0" STYLE="width: 100%; font: 10pt Times New Roman; margin-top: 0pt; margin-bottom: 0pt"><TR STYLE="vertical-align: top">
  <TD STYLE="width: 0%"></TD><TD STYLE="width: 0.5in"><B>Item 4.</B></TD><TD><B>Description of Securities</B>.</TD></TR></TABLE>
  
  <P STYLE="font: 10pt Times New Roman; margin: 0pt 0">&nbsp;</P>
  
  <P STYLE="font: 10pt Times New Roman; margin: 0pt 0; text-indent: 0.5in">Not applicable.</P>
  
  <P STYLE="font: 10pt Times New Roman; margin: 0pt 0">&nbsp;</P>
  
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  <P STYLE="font: 10pt Times New Roman; margin: 0pt 0">&nbsp;</P>
  
  <TABLE CELLPADDING="0" CELLSPACING="0" STYLE="width: 100%; font: 10pt Times New Roman; margin-top: 0pt; margin-bottom: 0pt"><TR STYLE="vertical-align: top">
  <TD STYLE="width: 0%"></TD><TD STYLE="width: 0.5in"><B>Item 5.</B></TD><TD><B>Interests of Named Experts and Counsel</B>.</TD></TR></TABLE>
  
  <P STYLE="font: 10pt Times New Roman; margin: 0pt 0">&nbsp;</P>
  
  <P STYLE="font: 10pt Times New Roman; margin: 0pt 0; text-indent: 0.5in">Not applicable.</P>
  
  <P STYLE="font: 10pt Times New Roman; margin: 0pt 0">&nbsp;</P>
  
  <TABLE CELLPADDING="0" CELLSPACING="0" STYLE="width: 100%; font: 10pt Times New Roman; margin-top: 0pt; margin-bottom: 0pt"><TR STYLE="vertical-align: top">
  <TD STYLE="width: 0%"></TD><TD STYLE="width: 0.5in"><B>Item 6.</B></TD><TD><B>Indemnification of Directors and Officers</B>.</TD></TR></TABLE>
  
  <P STYLE="font: 10pt Times New Roman; margin: 0pt 0">&nbsp;</P>
  
  <P STYLE="font: 10pt Times New Roman; margin: 0pt 0; text-align: justify; text-indent: 0.5in">Section 102(b)(7) of the Delaware
  General Corporation Law, or the DGCL, provides that a Delaware corporation, in its certificate of incorporation, may limit the
  personal liability of a director to the corporation or its stockholders for monetary damages for breach of fiduciary duties as
  a director, except for liability for any:</P>
  
  <P STYLE="font: 10pt Times New Roman; margin: 0pt 0">&nbsp;</P>
  
  <TABLE CELLPADDING="0" CELLSPACING="0" WIDTH="100%" STYLE="font: 10pt Times New Roman; margin-top: 0pt; margin-bottom: 0pt"><TR STYLE="vertical-align: top">
  <TD STYLE="width: 0.5in"></TD><TD STYLE="width: 0.25in"><FONT STYLE="font-family: Symbol">&middot;</FONT></TD><TD STYLE="text-align: justify">transaction from which the director derived an improper personal benefit;</TD></TR></TABLE>
  
  <TABLE CELLPADDING="0" CELLSPACING="0" WIDTH="100%" STYLE="font: 10pt Times New Roman; margin-top: 0pt; margin-bottom: 0pt"><TR STYLE="vertical-align: top">
  <TD STYLE="width: 0.5in"></TD><TD STYLE="width: 0.25in"><FONT STYLE="font-family: Symbol">&middot;</FONT></TD><TD STYLE="text-align: justify">act or omission not in good faith or that involved intentional misconduct or a knowing violation
  of law;</TD></TR></TABLE>
  
  <TABLE CELLPADDING="0" CELLSPACING="0" WIDTH="100%" STYLE="font: 10pt Times New Roman; margin-top: 0pt; margin-bottom: 0pt"><TR STYLE="vertical-align: top">
  <TD STYLE="width: 0.5in"></TD><TD STYLE="width: 0.25in"><FONT STYLE="font-family: Symbol">&middot;</FONT></TD><TD STYLE="text-align: justify">unlawful payment of dividends or redemption of shares; or</TD></TR></TABLE>
  
  <TABLE CELLPADDING="0" CELLSPACING="0" WIDTH="100%" STYLE="font: 10pt Times New Roman; margin-top: 0pt; margin-bottom: 0pt"><TR STYLE="vertical-align: top">
  <TD STYLE="width: 0.5in"></TD><TD STYLE="width: 0.25in"><FONT STYLE="font-family: Symbol">&middot;</FONT></TD><TD STYLE="text-align: justify">breach of the director&rsquo;s duty of loyalty to the corporation or its stockholders.</TD></TR></TABLE>
  
  <P STYLE="font: 10pt Times New Roman; margin: 0pt 0">&nbsp;</P>
  
  <P STYLE="font: 10pt Times New Roman; margin: 0pt 0">&nbsp;</P>
  
  <P STYLE="font: 10pt Times New Roman; margin: 0pt 0; text-align: justify; text-indent: 0.5in">Section 145(a) of the DGCL provides,
  in general, that a Delaware corporation may indemnify any person who was or is a party, or is threatened to be made a party, to
  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 corporation) because that person is or was a director, officer, employee or agent of the
  corporation, or is or was serving at the request of the corporation as a director, officer, employee or agent of another corporation
  or other enterprise. The indemnity may include expenses (including attorneys&rsquo; fees), judgments, fines and amounts paid in
  settlement actually and reasonably incurred by the person in connection with such action, so long as the person acted in good faith
  and in a manner he or she reasonably believed was in or not opposed to the corporation&rsquo;s best interests, and, with respect
  to any criminal action or proceeding, had no reasonable cause to believe his or her conduct was unlawful.</P>
  
  <P STYLE="font: 10pt Times New Roman; margin: 0pt 0">&nbsp;</P>
  
  <P STYLE="font: 10pt Times New Roman; margin: 0pt 0; text-align: justify; text-indent: 0.5in">Section 145(b) of the DGCL provides,
  in general, that a Delaware corporation may indemnify any person who was or is a party, or is threatened to be made a party, to
  any threatened, pending or completed action or suit by or in the right of the corporation to obtain a judgment in its favor because
  the person is or was a director, officer, employee or agent of the corporation, or is or was serving at the request of the corporation
  as a director, officer, employee or agent of another corporation or other enterprise. The indemnity may include expenses (including
  attorneys&rsquo; fees) actually and reasonably incurred by the person in connection with the defense or settlement of such action,
  so long as the person acted in good faith and in a manner the person reasonably believed was in or not opposed to the corporation&rsquo;s
  best interests, except that no indemnification shall be permitted without judicial approval if a court has determined that the
  person is to be liable to the corporation with respect to such claim. Section 145(c) of the DGCL further provides that, if a present
  or former director or officer has been successful in defense of any action referred to above, the corporation must indemnify such
  officer or director against the expenses (including attorneys&rsquo; fees) he or she actually and reasonably incurred in connection
  with such action.</P>
  
  <P STYLE="font: 10pt Times New Roman; margin: 0pt 0">&nbsp;</P>
  
  <P STYLE="font: 10pt Times New Roman; margin: 0pt 0; text-align: justify; text-indent: 0.5in">Section 145(g) of the DGCL provides,
  in general, that a corporation may purchase and maintain insurance on behalf of any person who is or was a director, officer, employee
  or agent of the corporation, or is or was serving at the request of the corporation as a director, officer, employee or agent of
  another corporation or other enterprise against any liability asserted against and incurred by such person, in any such capacity,
  or arising out of his or her status as such, whether or not the corporation could indemnify the person against such liability under
  Section 145 of the DGCL.</P>
  
  <P STYLE="font: 10pt Times New Roman; margin: 0pt 0">&nbsp;</P>
  
  <P STYLE="font: 10pt Times New Roman; margin: 0pt 0; text-align: justify; text-indent: 0.5in">The Company&rsquo;s Amended and Restated
  Certificate of Incorporation, as amended, eliminates the personal liability of its directors to the Company or its stockholders
  for monetary damages for breach of fiduciary duty as a director, with certain limited exceptions set forth therein. The Company&rsquo;s
  Amended and Restated Bylaws provide for the indemnification of its directors and officers to the fullest extent permitted by the
  DGCL.</P>
  
  <P STYLE="font: 10pt Times New Roman; margin: 0pt 0">&nbsp;</P>
  
  <P STYLE="font: 10pt Times New Roman; margin: 0pt 0; text-align: justify; text-indent: 0.5in">The Company maintains an insurance
  policy that covers certain liabilities of its directors and officers arising out of claims based on acts or omissions in their
  capacities as directors or officers.</P>
  
  <P STYLE="font: 10pt Times New Roman; margin: 0pt 0">&nbsp;</P>
  
  <P STYLE="font: 10pt Times New Roman; margin: 0pt 0; text-align: justify; text-indent: 0.5in">In addition, the Company has entered
  into separate indemnification agreements with its directors and officers, pursuant to which the Company has agreed to indemnify
  its directors and officers against certain liabilities and expenses incurred by such persons in connection with claims by reason
  of their being such a director or officer.</P>
  
  <P STYLE="font: 10pt Times New Roman; margin: 0pt 0">&nbsp;</P>
  
  <P STYLE="font: 10pt Times New Roman; margin: 0pt 0; text-align: justify; text-indent: 0.5in">Certain of the Company&rsquo;s non-employee
  directors may, through their relationships with their employers, also be insured and/or indemnified against certain liabilities
  incurred in their capacity as members of the Company&rsquo;s board of directors.</P>
  
  <P STYLE="font: 10pt Times New Roman; margin: 0pt 0">&nbsp;</P>
  
  <!-- Field: Page; Sequence: 4 -->
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      <DIV STYLE="page-break-before: always; margin-top: 6pt; margin-bottom: 8pt"><TABLE CELLPADDING="0" CELLSPACING="0" STYLE="width: 100%"><TR><TD STYLE="text-align: left; width: 100%"><FONT STYLE="font-size: 8pt">&nbsp;</FONT></TD></TR></TABLE></DIV>
      <!-- Field: /Page -->
  
  <P STYLE="font: 10pt Times New Roman; margin: 0pt 0">&nbsp;</P>
  
  <P STYLE="font: 10pt Times New Roman; margin: 0pt 0; text-align: justify; text-indent: 0.5in">The foregoing descriptions are only
  general summaries.</P>
  
  <P STYLE="font: 10pt Times New Roman; margin: 0pt 0">&nbsp;</P>
  
  <TABLE CELLPADDING="0" CELLSPACING="0" STYLE="width: 100%; font: 10pt Times New Roman; margin-top: 0pt; margin-bottom: 0pt"><TR STYLE="vertical-align: top">
  <TD STYLE="width: 0%"></TD><TD STYLE="width: 0.5in"><B>Item 7.</B></TD><TD><B>Exemption from Registration Claimed</B>.</TD></TR></TABLE>
  
  <P STYLE="font: 10pt Times New Roman; margin: 0pt 0">&nbsp;</P>
  
  <P STYLE="font: 10pt Times New Roman; margin: 0pt 0; text-align: justify; text-indent: 0.5in">Not applicable.</P>
  
  <P STYLE="font: 10pt Times New Roman; margin: 0pt 0">&nbsp;</P>
  
  <TABLE CELLPADDING="0" CELLSPACING="0" STYLE="width: 100%; font: 10pt Times New Roman; margin-top: 0pt; margin-bottom: 0pt"><TR STYLE="vertical-align: top">
  <TD STYLE="width: 0%"></TD><TD STYLE="width: 0.5in"><B>Item 8.</B></TD><TD><B>Exhibits</B>.</TD></TR></TABLE>
  
  <P STYLE="font: 10pt Times New Roman; margin: 0pt 0 0pt 1in; text-align: justify; text-indent: -1in">&nbsp;</P>
  
  <P STYLE="font: 10pt Times New Roman; margin: 0pt 0 0pt 0.5in">The exhibits below represent a complete list of exhibits filed or
  incorporated by reference as part of this Registration Statement.</P>
  
  <P STYLE="font: 10pt Times New Roman; margin: 0pt 0 0pt 1in; text-align: justify; text-indent: -1in">&nbsp;</P>
  
  <P STYLE="font: 10pt Times New Roman; margin: 0pt 0">&nbsp;</P>
  
  <TABLE CELLSPACING="0" CELLPADDING="0" STYLE="font: 10pt Times New Roman, Times, Serif; width: 100%; border-collapse: collapse">
  <TR STYLE="vertical-align: bottom">
      <TD STYLE="border: Black 1pt solid; white-space: nowrap; width: 11%; text-align: center"><FONT STYLE="font-size: 10pt"><B>Exhibit No.</B></FONT></TD>
      <TD STYLE="white-space: nowrap; width: 1%; border-top: Black 1pt solid; border-right: Black 1pt solid; border-bottom: Black 1pt solid; text-align: center">&nbsp;</TD>
      <TD STYLE="white-space: nowrap; width: 88%; border-top: Black 1pt solid; border-right: Black 1pt solid; border-bottom: Black 1pt solid; text-align: center"><FONT STYLE="font-size: 10pt"><B>Exhibit</B></FONT></TD></TR>
  <TR>
      <TD STYLE="white-space: nowrap; vertical-align: top; border-right: Black 1pt solid; border-bottom: Black 1pt solid; border-left: Black 1pt solid">&nbsp;</TD>
      <TD STYLE="vertical-align: bottom; border-right: Black 1pt solid; border-bottom: Black 1pt solid">&nbsp;</TD>
      <TD STYLE="vertical-align: top; border-right: Black 1pt solid; border-bottom: Black 1pt solid">&nbsp;</TD></TR>
  <TR>
      <TD STYLE="white-space: nowrap; vertical-align: top; border-right: Black 1pt solid; border-bottom: Black 1pt solid; border-left: Black 1pt solid; text-align: center">&nbsp;</TD>
      <TD STYLE="vertical-align: bottom; border-right: Black 1pt solid; border-bottom: Black 1pt solid">&nbsp;</TD>
      <TD STYLE="vertical-align: top; border-right: Black 1pt solid; border-bottom: Black 1pt solid">&nbsp;</TD></TR>
  <TR>
      <TD STYLE="white-space: nowrap; vertical-align: top; border-right: Black 1pt solid; border-bottom: Black 1pt solid; border-left: Black 1pt solid; text-align: center"><FONT STYLE="font-size: 10pt">5.1</FONT></TD>
      <TD STYLE="vertical-align: bottom; border-right: Black 1pt solid; border-bottom: Black 1pt solid">&nbsp;</TD>
      <TD STYLE="vertical-align: top; border-right: Black 1pt solid; border-bottom: Black 1pt solid"><A HREF="ex5_1.htm"><FONT STYLE="font-size: 10pt">Opinion of Polsinelli PC.</FONT></A></TD></TR>
  <TR>
      <TD STYLE="white-space: nowrap; vertical-align: top; border-right: Black 1pt solid; border-bottom: Black 1pt solid; border-left: Black 1pt solid; text-align: center">&nbsp;</TD>
      <TD STYLE="vertical-align: bottom; border-right: Black 1pt solid; border-bottom: Black 1pt solid">&nbsp;</TD>
      <TD STYLE="vertical-align: top; border-right: Black 1pt solid; border-bottom: Black 1pt solid">&nbsp;</TD></TR>
  <TR>
      <TD STYLE="white-space: nowrap; vertical-align: top; border-right: Black 1pt solid; border-bottom: Black 1pt solid; border-left: Black 1pt solid; text-align: center"><FONT STYLE="font-size: 10pt">10.1</FONT></TD>
      <TD STYLE="vertical-align: bottom; border-right: Black 1pt solid; border-bottom: Black 1pt solid">&nbsp;</TD>
      <TD STYLE="vertical-align: top; border-right: Black 1pt solid; border-bottom: Black 1pt solid"><FONT STYLE="font-size: 10pt"><A HREF="https://www.sec.gov/Archives/edgar/data/1293310/000121465920007809/ex10_1.htm">Humanigen, Inc. 2020 Omnibus Incentive Compensation Plan</A> (incorporated by reference to Exhibit 10.1 to the Company&rsquo;s Current Report on Form 8-K filed on September 11, 2020 (File No. 001-35798)).</FONT></TD></TR>
  <TR>
      <TD STYLE="white-space: nowrap; vertical-align: top; border-right: Black 1pt solid; border-bottom: Black 1pt solid; border-left: Black 1pt solid">&nbsp;</TD>
      <TD STYLE="vertical-align: bottom; border-right: Black 1pt solid; border-bottom: Black 1pt solid">&nbsp;</TD>
      <TD STYLE="vertical-align: top; border-right: Black 1pt solid; border-bottom: Black 1pt solid">&nbsp;</TD></TR>
  <TR>
      <TD STYLE="white-space: nowrap; vertical-align: top; border-right: Black 1pt solid; border-bottom: Black 1pt solid; border-left: Black 1pt solid; text-align: center"><FONT STYLE="font-size: 10pt">23.1</FONT></TD>
      <TD STYLE="vertical-align: bottom; border-right: Black 1pt solid; border-bottom: Black 1pt solid">&nbsp;</TD>
      <TD STYLE="vertical-align: top; border-right: Black 1pt solid; border-bottom: Black 1pt solid"><A HREF="ex23_1.htm"><FONT STYLE="font-size: 10pt">Consent of HORNE LLP.</FONT></A></TD></TR>
  <TR>
      <TD STYLE="white-space: nowrap; vertical-align: top; border-right: Black 1pt solid; border-bottom: Black 1pt solid; border-left: Black 1pt solid; text-align: center">&nbsp;</TD>
      <TD STYLE="vertical-align: bottom; border-right: Black 1pt solid; border-bottom: Black 1pt solid">&nbsp;</TD>
      <TD STYLE="vertical-align: top; border-right: Black 1pt solid; border-bottom: Black 1pt solid">&nbsp;</TD></TR>
  <TR>
      <TD STYLE="white-space: nowrap; vertical-align: top; border-right: Black 1pt solid; border-bottom: Black 1pt solid; border-left: Black 1pt solid; text-align: center"><FONT STYLE="font-size: 10pt">23.2</FONT></TD>
      <TD STYLE="vertical-align: bottom; border-right: Black 1pt solid; border-bottom: Black 1pt solid">&nbsp;</TD>
      <TD STYLE="vertical-align: top; border-right: Black 1pt solid; border-bottom: Black 1pt solid"><A HREF="ex5_1.htm"><FONT STYLE="font-size: 10pt">Consent of Polsinelli PC (included in Exhibit 5.1).</FONT></A></TD></TR>
  <TR>
      <TD STYLE="white-space: nowrap; vertical-align: top; border-right: Black 1pt solid; border-bottom: Black 1pt solid; border-left: Black 1pt solid; text-align: center">&nbsp;</TD>
      <TD STYLE="vertical-align: bottom; border-right: Black 1pt solid; border-bottom: Black 1pt solid">&nbsp;</TD>
      <TD STYLE="vertical-align: top; border-right: Black 1pt solid; border-bottom: Black 1pt solid">&nbsp;</TD></TR>
  <TR>
      <TD STYLE="white-space: nowrap; vertical-align: top; border-right: Black 1pt solid; border-bottom: Black 1pt solid; border-left: Black 1pt solid; text-align: center"><FONT STYLE="font-size: 10pt">24.1</FONT></TD>
      <TD STYLE="vertical-align: bottom; border-right: Black 1pt solid; border-bottom: Black 1pt solid">&nbsp;</TD>
      <TD STYLE="vertical-align: top; border-right: Black 1pt solid; border-bottom: Black 1pt solid"><A HREF="#poasig"><FONT STYLE="font-size: 10pt">Power of Attorney. Included on the signature page of the Registration Statement.</FONT></A></TD></TR>
  </TABLE>
  <P STYLE="font: 10pt Times New Roman; margin: 0pt 0">&nbsp;</P>
  
  <!-- Field: Page; Sequence: 5 -->
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      <DIV STYLE="page-break-before: always; margin-top: 6pt; margin-bottom: 8pt"><TABLE CELLPADDING="0" CELLSPACING="0" STYLE="width: 100%"><TR><TD STYLE="text-align: left; width: 100%"><FONT STYLE="font-size: 8pt">&nbsp;</FONT></TD></TR></TABLE></DIV>
      <!-- Field: /Page -->
  
  <P STYLE="font: 10pt Times New Roman; margin: 0pt 0">&nbsp;</P>
  
  <TABLE CELLPADDING="0" CELLSPACING="0" STYLE="width: 100%; font: 10pt Times New Roman; margin-top: 0pt; margin-bottom: 0pt"><TR STYLE="vertical-align: top">
  <TD STYLE="width: 0%"></TD><TD STYLE="width: 0.5in"><B>Item 9.</B></TD><TD><B>Undertakings</B>.</TD></TR></TABLE>
  
  <P STYLE="font: 10pt Times New Roman; margin: 0pt 0 0pt 1in; text-align: justify; text-indent: -1in">&nbsp;</P>
  
  <P STYLE="font: 10pt Times New Roman; margin: 0pt 0; text-align: justify">A. The undersigned Registrant hereby undertakes:</P>
  
  <P STYLE="font: 10pt Times New Roman; margin: 0pt 0">&nbsp;</P>
  
  <P STYLE="font: 10pt Times New Roman; margin: 0pt 0; text-align: justify; text-indent: 24.5pt">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; margin: 0pt 0">&nbsp;</P>
  
  <P STYLE="font: 10pt Times New Roman; margin: 0pt 0; text-align: justify; text-indent: 24.5pt">(i) To include any prospectus required
  by Section 10(a)(3) of the Securities Act of 1933;</P>
  
  <P STYLE="font: 10pt Times New Roman; margin: 0pt 0">&nbsp;</P>
  
  <P STYLE="font: 10pt Times New Roman; margin: 0pt 0; text-align: justify; text-indent: 24.5pt">(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. Notwithstanding the foregoing, any increase or decrease in volume of securities offered (if the total dollar value of
  securities offered would not exceed that which was registered) and any deviation from the low or high end of the estimated maximum
  offering range may be reflected in the form of prospectus filed with the Commission pursuant to Rule 424(b) if, in the aggregate,
  the changes in volume and price represent no more than 20% change in the maximum aggregate offering price set forth in the &ldquo;Calculation
  of Registration Fee&rdquo; table in the effective Registration Statement.</P>
  
  <P STYLE="font: 10pt Times New Roman; margin: 0pt 0">&nbsp;</P>
  
  <P STYLE="font: 10pt Times New Roman; margin: 0pt 0; text-align: justify; text-indent: 24.5pt">(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; margin: 0pt 0">&nbsp;</P>
  
  <P STYLE="font: 10pt Times New Roman; margin: 0pt 0; text-align: justify; text-indent: 24.5pt"><I>Provided, however,</I> that paragraphs
  (A)(1)(i) and (A)(1)(ii) above 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 Securities Exchange Act of 1934 that are incorporated by reference in the Registration Statement.</P>
  
  <P STYLE="font: 10pt Times New Roman; margin: 0pt 0">&nbsp;</P>
  
  <P STYLE="font: 10pt Times New Roman; margin: 0pt 0; text-align: justify; text-indent: 24.5pt">2. That, for the purpose of determining
  any liability under the Securities Act of 1933, each such post-effective amendment shall be deemed to be a new registration statement
  relating to the securities offered herein, 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; margin: 0pt 0">&nbsp;</P>
  
  <P STYLE="font: 10pt Times New Roman; margin: 0pt 0; text-align: justify; text-indent: 24.5pt">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; margin: 0pt 0">&nbsp;</P>
  
  <P STYLE="font: 10pt Times New Roman; margin: 0pt 0; text-align: justify">B. The undersigned Registrant hereby undertakes that,
  for purposes of determining any liability under the Securities Act of 1933, each filing of the Registrant&rsquo;s annual report
  pursuant to Section 13(a) or Section 15(d) of the Securities Exchange Act of 1934 (and, where applicable, each filing of an employee
  benefit plan&rsquo;s annual report pursuant to Section 15(d) of the Securities Exchange Act of 1934) that is incorporated by reference
  in the Registration Statement shall be deemed to be a new registration statement relating to the securities offered herein, 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; margin: 0pt 0">&nbsp;</P>
  
  <P STYLE="font: 10pt Times New Roman; margin: 0pt 0; text-align: justify">C. Insofar as indemnification for liabilities arising
  under the Securities Act of 1933 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 of 1933 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 of 1933 and will be governed
  by the final adjudication of such issue.</P>
  
  <P STYLE="font: 10pt Times New Roman; margin: 0pt 0">&nbsp;</P>
  
  <!-- Field: Page; Sequence: 6 -->
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      <DIV STYLE="page-break-before: always; margin-top: 6pt; margin-bottom: 8pt"><TABLE CELLPADDING="0" CELLSPACING="0" STYLE="width: 100%"><TR><TD STYLE="text-align: left; width: 100%"><FONT STYLE="font-size: 8pt">&nbsp;</FONT></TD></TR></TABLE></DIV>
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  <P STYLE="font: 10pt Times New Roman; margin: 0pt 0">&nbsp;</P>
  
  <P STYLE="font: 10pt Times New Roman; margin: 0pt 0; text-align: center"><B>SIGNATURE</B></P>
  
  <P STYLE="font: 10pt Times New Roman; margin: 0pt 0">&nbsp;</P>
  
  <P STYLE="font: 10pt Times New Roman; margin: 0pt 0; text-align: justify; text-indent: 0.5in">Pursuant to the requirements of the
  Securities Act of 1933, 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 Burlingame, State of California on September 14, 2020.&nbsp;</P>
  
  <P STYLE="font: 10pt Times New Roman; margin: 0pt 0">&nbsp;</P>
  
  <TABLE CELLSPACING="0" CELLPADDING="0" STYLE="font: 10pt Times New Roman, Times, Serif; width: 100%; border-collapse: collapse">
  <TR STYLE="vertical-align: top">
      <TD>&nbsp;</TD>
      <TD COLSPAN="2"><FONT STYLE="font-size: 10pt">Humanigen, Inc.</FONT></TD></TR>
  <TR STYLE="vertical-align: top">
      <TD>&nbsp;</TD>
      <TD COLSPAN="2">&nbsp;</TD></TR>
  <TR STYLE="vertical-align: top">
      <TD STYLE="padding-bottom: 1pt; width: 50%">&nbsp;</TD>
      <TD STYLE="padding-bottom: 1pt; width: 3%"><FONT STYLE="font-size: 10pt">By:&nbsp;&nbsp;</FONT></TD>
      <TD STYLE="border-bottom: Black 1pt solid; width: 47%"><FONT STYLE="font-size: 10pt">/s/ Cameron Durrant</FONT></TD></TR>
  <TR STYLE="vertical-align: top">
      <TD>&nbsp;</TD>
      <TD>&nbsp;</TD>
      <TD><FONT STYLE="font-size: 10pt">Cameron Durrant, M.D., MBA</FONT></TD></TR>
  <TR STYLE="vertical-align: top">
      <TD>&nbsp;</TD>
      <TD>&nbsp;</TD>
      <TD><FONT STYLE="font-size: 10pt">Chairman of the Board and Chief Executive Officer</FONT></TD></TR>
  </TABLE>
  <P STYLE="font: 10pt Times New Roman; margin: 0pt 0">&nbsp;</P>
  
  <P STYLE="font: 10pt Times New Roman; margin: 0pt 0; text-align: center"><A NAME="poasig"></A><B>POWER OF ATTORNEY AND SIGNATURES</B></P>
  
  <P STYLE="font: 10pt Times New Roman; margin: 0pt 0">&nbsp;</P>
  
  <P STYLE="font: 10pt Times New Roman; margin: 0pt 0; text-align: justify; text-indent: 0.5in">Each person whose signature appears
  below constitutes and appoints Cameron Durrant, Timothy Morris and David Tousley, and each of them, his or her true and lawful
  attorneys-in-fact and agents, 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, without limitation, 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 Exchange Commission, under the Securities Act of 1933, 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, as fully to
  all intents and purposes as he or she might or could do in person, hereby ratifying and confirming all that each of said attorneys-in-fact
  and agents or their substitute or substitutes may lawfully do or cause to be done by virtue hereof.</P>
  
  <P STYLE="font: 10pt Times New Roman; margin: 0pt 0; text-indent: 0.5in">&nbsp;</P>
  
  <P STYLE="font: 10pt Times New Roman; margin: 0pt 0; text-indent: 0.5in">Pursuant to the requirements of the Securities Act of
  1933, this Registration Statement on Form S-8 has been signed by the following persons in the capacities and on the dates indicated.</P>
  
  <P STYLE="font: 10pt Times New Roman; margin: 0pt 0">&nbsp;</P>
  
  <TABLE CELLSPACING="0" CELLPADDING="0" STYLE="font: 10pt Times New Roman, Times, Serif; width: 100%; border-collapse: collapse">
  <TR STYLE="vertical-align: top">
      <TD STYLE="border-bottom: Black 1pt solid; white-space: nowrap; width: 34%; text-align: center"><FONT STYLE="font-size: 10pt"><B>Signature</B></FONT></TD>
      <TD STYLE="padding-bottom: 1pt; white-space: nowrap; width: 2%; text-align: center">&nbsp;</TD>
      <TD STYLE="border-bottom: Black 1pt solid; white-space: nowrap; width: 46%; text-align: center"><FONT STYLE="font-size: 10pt"><B>Title</B></FONT></TD>
      <TD STYLE="padding-bottom: 1pt; white-space: nowrap; width: 2%; text-align: center">&nbsp;</TD>
      <TD STYLE="border-bottom: Black 1pt solid; white-space: nowrap; width: 16%; text-align: center"><FONT STYLE="font-size: 10pt"><B>Date</B></FONT></TD></TR>
  <TR STYLE="vertical-align: top">
      <TD STYLE="white-space: nowrap">&nbsp;</TD>
      <TD>&nbsp;</TD>
      <TD STYLE="white-space: nowrap; text-align: center">&nbsp;</TD>
      <TD STYLE="text-align: center">&nbsp;</TD>
      <TD STYLE="white-space: nowrap; text-align: center">&nbsp;</TD></TR>
  <TR STYLE="vertical-align: top">
      <TD STYLE="border-bottom: Black 1pt solid; white-space: nowrap; padding-left: 10pt; text-indent: -10pt"><FONT STYLE="font-size: 10pt">/s/ Cameron Durrant</FONT></TD>
      <TD STYLE="padding-bottom: 1pt">&nbsp;</TD>
      <TD STYLE="padding-bottom: 1pt; white-space: nowrap">&nbsp;</TD>
      <TD STYLE="padding-bottom: 1pt">&nbsp;</TD>
      <TD STYLE="padding-bottom: 1pt; white-space: nowrap">&nbsp;</TD></TR>
  <TR STYLE="vertical-align: top">
      <TD STYLE="white-space: nowrap"><FONT STYLE="font-size: 10pt">Cameron Durrant, M.D., MBA</FONT></TD>
      <TD>&nbsp;</TD>
      <TD STYLE="white-space: nowrap"><FONT STYLE="font-size: 10pt">Chairman of the Board and Chief Executive Officer<BR>
  (Principal Executive Officer)</FONT></TD>
      <TD>&nbsp;</TD>
      <TD STYLE="white-space: nowrap"><FONT STYLE="font-size: 10pt">September 14, 2020</FONT></TD></TR>
  <TR STYLE="vertical-align: top">
      <TD STYLE="white-space: nowrap">&nbsp;</TD>
      <TD>&nbsp;</TD>
      <TD STYLE="white-space: nowrap">&nbsp;</TD>
      <TD>&nbsp;</TD>
      <TD STYLE="white-space: nowrap">&nbsp;</TD></TR>
  <TR STYLE="vertical-align: top">
      <TD STYLE="border-bottom: Black 1pt solid; white-space: nowrap"><FONT STYLE="font-size: 10pt">/s/ Timothy Morris</FONT></TD>
      <TD STYLE="padding-bottom: 1pt">&nbsp;</TD>
      <TD STYLE="padding-bottom: 1pt; white-space: nowrap">&nbsp;</TD>
      <TD STYLE="padding-bottom: 1pt">&nbsp;</TD>
      <TD STYLE="padding-bottom: 1pt; white-space: nowrap">&nbsp;</TD></TR>
  <TR STYLE="vertical-align: top">
      <TD STYLE="white-space: nowrap"><FONT STYLE="font-size: 10pt">Timothy Morris, CPA</FONT></TD>
      <TD>&nbsp;</TD>
      <TD STYLE="white-space: nowrap"><FONT STYLE="font-size: 10pt">Chief Operating Officer and Chief Financial Officer <BR>
  (Principal Financial Officer)</FONT></TD>
      <TD>&nbsp;</TD>
      <TD STYLE="white-space: nowrap"><FONT STYLE="font-size: 10pt">September 14, 2020</FONT></TD></TR>
  <TR STYLE="vertical-align: top">
      <TD STYLE="white-space: nowrap">&nbsp;</TD>
      <TD>&nbsp;</TD>
      <TD STYLE="white-space: nowrap">&nbsp;</TD>
      <TD>&nbsp;</TD>
      <TD STYLE="white-space: nowrap">&nbsp;</TD></TR>
  <TR STYLE="vertical-align: top">
      <TD STYLE="border-bottom: Black 1pt solid; white-space: nowrap">
  
  <P STYLE="font: 10pt Times New Roman; margin: 0pt 0">/s/ David Tousley</P></TD>
      <TD STYLE="padding-bottom: 1pt">&nbsp;</TD>
      <TD STYLE="padding-bottom: 1pt; white-space: nowrap">&nbsp;</TD>
      <TD STYLE="padding-bottom: 1pt">&nbsp;</TD>
      <TD STYLE="padding-bottom: 1pt; white-space: nowrap">&nbsp;</TD></TR>
  <TR STYLE="vertical-align: top">
      <TD STYLE="white-space: nowrap"><FONT STYLE="font-size: 10pt">David Tousley, MBA, CPA</FONT></TD>
      <TD>&nbsp;</TD>
      <TD STYLE="white-space: nowrap">
          <P STYLE="font: 10pt Times New Roman; margin: 0pt 0">Chief Accounting and Administrative Officer,<BR>
          Corporate Secretary and Treasurer</P>
          <P STYLE="font: 10pt Times New Roman; margin: 0pt 0">(Principal Accounting Officer)</P></TD>
      <TD>&nbsp;</TD>
      <TD STYLE="white-space: nowrap"><FONT STYLE="font-size: 10pt">September 14, 2020</FONT></TD></TR>
  <TR STYLE="vertical-align: top">
      <TD STYLE="white-space: nowrap">&nbsp;</TD>
      <TD>&nbsp;</TD>
      <TD STYLE="white-space: nowrap">&nbsp;</TD>
      <TD>&nbsp;</TD>
      <TD STYLE="white-space: nowrap">&nbsp;</TD></TR>
  <TR STYLE="vertical-align: top">
      <TD STYLE="border-bottom: Black 1pt solid; white-space: nowrap"><FONT STYLE="font-size: 10pt">/s/ Ronald Barliant</FONT></TD>
      <TD STYLE="padding-bottom: 1pt">&nbsp;</TD>
      <TD STYLE="padding-bottom: 1pt; white-space: nowrap">&nbsp;</TD>
      <TD STYLE="padding-bottom: 1pt">&nbsp;</TD>
      <TD STYLE="padding-bottom: 1pt; white-space: nowrap">&nbsp;</TD></TR>
  <TR STYLE="vertical-align: top">
      <TD STYLE="white-space: nowrap"><FONT STYLE="font-size: 10pt">Ronald Barliant, JD</FONT></TD>
      <TD>&nbsp;</TD>
      <TD STYLE="white-space: nowrap"><FONT STYLE="font-size: 10pt">Director</FONT></TD>
      <TD>&nbsp;</TD>
      <TD STYLE="white-space: nowrap"><FONT STYLE="font-size: 10pt">September 14, 2020</FONT></TD></TR>
  <TR STYLE="vertical-align: top">
      <TD STYLE="white-space: nowrap">&nbsp;</TD>
      <TD>&nbsp;</TD>
      <TD STYLE="white-space: nowrap">&nbsp;</TD>
      <TD>&nbsp;</TD>
      <TD STYLE="white-space: nowrap">&nbsp;</TD></TR>
  <TR STYLE="vertical-align: top">
      <TD STYLE="border-bottom: Black 1pt solid; white-space: nowrap"><FONT STYLE="font-size: 10pt">/s/ Rainer Boehm</FONT></TD>
      <TD STYLE="padding-bottom: 1pt">&nbsp;</TD>
      <TD STYLE="padding-bottom: 1pt; white-space: nowrap">&nbsp;</TD>
      <TD STYLE="padding-bottom: 1pt">&nbsp;</TD>
      <TD STYLE="padding-bottom: 1pt; white-space: nowrap">&nbsp;</TD></TR>
  <TR STYLE="vertical-align: top">
      <TD STYLE="white-space: nowrap"><FONT STYLE="font-size: 10pt">Rainer Boehm, M.D.</FONT></TD>
      <TD>&nbsp;</TD>
      <TD STYLE="white-space: nowrap"><FONT STYLE="font-size: 10pt">Director</FONT></TD>
      <TD>&nbsp;</TD>
      <TD STYLE="white-space: nowrap"><FONT STYLE="font-size: 10pt">September 14, 2020</FONT></TD></TR>
  <TR STYLE="vertical-align: top">
      <TD STYLE="white-space: nowrap">&nbsp;</TD>
      <TD>&nbsp;</TD>
      <TD STYLE="white-space: nowrap">&nbsp;</TD>
      <TD>&nbsp;</TD>
      <TD STYLE="white-space: nowrap">&nbsp;</TD></TR>
  <TR STYLE="vertical-align: top">
      <TD STYLE="border-bottom: Black 1pt solid; white-space: nowrap"><FONT STYLE="font-size: 10pt">/s/ Cheryl Buxton</FONT></TD>
      <TD STYLE="padding-bottom: 1pt">&nbsp;</TD>
      <TD STYLE="padding-bottom: 1pt; white-space: nowrap">&nbsp;</TD>
      <TD STYLE="padding-bottom: 1pt">&nbsp;</TD>
      <TD STYLE="padding-bottom: 1pt; white-space: nowrap">&nbsp;</TD></TR>
  <TR STYLE="vertical-align: top">
      <TD STYLE="white-space: nowrap"><FONT STYLE="font-size: 10pt">Cheryl Buxton</FONT></TD>
      <TD>&nbsp;</TD>
      <TD STYLE="white-space: nowrap"><FONT STYLE="font-size: 10pt">Director</FONT></TD>
      <TD>&nbsp;</TD>
      <TD STYLE="white-space: nowrap"><FONT STYLE="font-size: 10pt">September 14, 2020</FONT></TD></TR>
  <TR STYLE="vertical-align: top">
      <TD STYLE="white-space: nowrap">&nbsp;</TD>
      <TD>&nbsp;</TD>
      <TD STYLE="white-space: nowrap">&nbsp;</TD>
      <TD>&nbsp;</TD>
      <TD STYLE="white-space: nowrap">&nbsp;</TD></TR>
  <TR STYLE="vertical-align: top">
      <TD STYLE="border-bottom: Black 1pt solid; white-space: nowrap"><FONT STYLE="font-size: 10pt">/s/ Robert G. Savage</FONT></TD>
      <TD STYLE="padding-bottom: 1pt">&nbsp;</TD>
      <TD STYLE="padding-bottom: 1pt; white-space: nowrap">&nbsp;</TD>
      <TD STYLE="padding-bottom: 1pt">&nbsp;</TD>
      <TD STYLE="padding-bottom: 1pt; white-space: nowrap">&nbsp;</TD></TR>
  <TR STYLE="vertical-align: top">
      <TD STYLE="white-space: nowrap"><FONT STYLE="font-size: 10pt">Robert G. Savage, MBA</FONT></TD>
      <TD>&nbsp;</TD>
      <TD STYLE="white-space: nowrap"><FONT STYLE="font-size: 10pt">Director</FONT></TD>
      <TD>&nbsp;</TD>
      <TD STYLE="white-space: nowrap"><FONT STYLE="font-size: 10pt">September 14, 2020</FONT></TD></TR>
  </TABLE>
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metadata_documents: [{"type": "S-8", "sequence": "1", "filename": "g99201s8.htm", "secsgml_size_bytes": 59282}]
metadata_filer: {"company-data": {"conformed-name": "HUMANIGEN, INC", "cik": "0001293310", "assigned-sic": "2834", "irs-number": "770557236", "state-of-incorporation": "DE", "fiscal-year-end": "1231"}, "filing-values": {"form-type": "S-8", "act": "33", "file-number": "333-248793", "film-number": "201173948"}, "business-address": {"street1": "533 AIRPORT BLVD.", "street2": "SUITE 400", "city": "BURLINGAME", "state": "CA", "zip": "94010", "phone": "650.243.3100"}, "mail-address": {"street1": "533 AIRPORT BLVD.", "street2": "SUITE 400", "city": "BURLINGAME", "state": "CA", "zip": "94010"}, "former-company": {"former-conformed-name": "KALOBIOS PHARMACEUTICALS INC", "date-changed": "20040609"}}
text: As filed with the Securities and Exchange Commission on
  September 14, 2020
  Registration No. 333-
  UNITED STATES
  SECURITIES
  AND EXCHANGE COMMISSION
  Washington, D.C. 20549
  Form S-8
  REGISTRATION STATEMENT
  UNDER THE SECURITIES ACT OF
  1933
  Humanigen, Inc.
  (Exact name of registrant as
  specified in its charter)
  Delaware
  77-0557236
  (State or other jurisdiction of
  incorporation or organization)
  (IRS employer identification
  number)
  533 Airport Boulevard, Suite
  400
  Burlingame, CA 94010
  (Address of principal executive
  offices)
  Humanigen, Inc. 2020 Omnibus
  Incentive Compensation Plan
  (Full title of the Plan)
  Cameron Durrant, M.D.
  Chief Executive Officer
  Humanigen, Inc.
  533 Airport Boulevard, Suite
  400
  Burlingame, CA 94010
  (650) 243-1000
  (Name, address and telephone
  number of Agent for Service)
  Copy to
  :
  Kevin L. Vold, Esq.
  Polsinelli PC
  1401 Eye Street, NW, Suite
  800
  Washington, D.C. 20005
  (202) 783-3300
  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. (Check one):
  Large accelerated filer
  o
  Accelerated filer
  o
  Non-accelerated filer
  x
  Smaller reporting company
  x
  Emerging growth company
  o
  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.
  o
  CALCULATION OF REGISTRATION FEE
  Title of Securities
  to be
  Registered
  Amount
  to be
  Registered
  (1)
  Proposed
  Maximum
  Offering
  Price
  per Share
  (2)
  Proposed
  Maximum
  Aggregate
  Offering
  Price
  Amount of
  Registration
  Fee
  Common stock, $0.001 par value per share
  7,000,000
  $9.95
  $69,650,000
  $9,040.57
  (1) Consists of shares of common stock, $0.001 par value
  per share of the Registrant, or Common Stock, authorized for issuance under the Humanigen, Inc. 2020 Omnibus Incentive Compensation
  Plan and reflects a reverse stock split effective September 11, 2020. Pursuant to Rule 416 of the Securities Act of 1933,
  as amended (the "Securities Act"), this registration statement also covers any additional shares of common stock which
  become issuable under the above-named plan by reason of any share dividend, share split, recapitalization or any other similar
  transaction without receipt of consideration which results in an increase in the number of shares or common stock outstanding.
  (2) Estimated pursuant to Rule 457(c) and Rule 457(h)
  of the Securities Act solely for the purpose of calculating the registration fee. The price per share is based on the average of
  the high and low sales price on the OTCQB Venture Market on September 14, 2020.
  PART I
  INFORMATION REQUIRED IN THE SECTION 10(a) PROSPECTUS
  The documents containing the information
  specified in Part I will be sent or given to employees and other individuals participating in the Humanigen, Inc. 2020 Omnibus
  Incentive Compensation Plan (the "Plan") in accordance with Rule 428(b)(1) under the Securities Act of 1933, as amended,
  or the Securities Act. Such information is omitted from this Registration Statement in accordance with Rule 428 of the Securities
  Act and the instructions to Form S-8. In accordance with the rules and regulations of the Securities and Exchange Commission, or
  the SEC, and the instructions to Form S-8, such documents are not being filed with the SEC either as part of this Registration
  Statement or as prospectuses or prospectus supplements pursuant to Rule 424.
  PART II
  INFORMATION REQUIRED IN THE REGISTRATION STATEMENT
  Item 3.
  Incorporation of Documents by Reference.
  Humanigen, Inc., or the Company,
  hereby incorporates by reference into this Registration Statement the following documents filed by it with the SEC:
  (a)
  the Company's Annual Report on Form 10-K for the fiscal year ended December 31, 2019, filed with the SEC on March 16,
  2020 (File No. 001-35798);
  (b)
  the Company's Quarterly Report on Form 10-Q for the quarterly period ended March 31, 2020, filed with the SEC on May
  15, 2020, and the Company's Quarterly Report on Form 10-Q for the quarterly period ended June 30, 2020, filed with the SEC
  on August 14, 2020;
  (c)
  our Current Reports on Form 8-K, filed with the SEC on January 31, 2020; March 20, 2020; March 23, 2020; April 6, 2020; April
  29, 2020; May 7, 2020; June 4, 2020; July 6, 2020; July 10, 2020; July 30, 2020; August 3, 2020; September 4, 2020; and September
  11, 2020 (except, with respect to each of the foregoing, for portions of such reports which were deemed to be furnished and not
  filed); and
  (d)
  the description of the Company's common stock contained in Exhibit 4.5 to the Company's Annual Report on Form 10-K
  for the fiscal year ended December 31, 2019, filed with the SEC on March 16, 2020, including any other amendments or reports filed
  for the purpose of updating such description.
  All reports and other documents subsequently
  filed by the Company pursuant to Sections 13(a), 13(c), 14 or 15(d) of the Securities Exchange Act of 1934, as amended, or the
  Exchange Act, prior to the filing of a post-effective amendment that indicates that all securities offered hereby have been sold
  or that deregisters all securities then remaining unsold, shall be deemed to be incorporated by reference herein and to be a part
  hereof from the date of filing of such documents. Unless specifically stated to the contrary, none of the information that the
  Company discloses under Items 2.02 or 7.01 of any Current Report on Form 8-K that the Company has or may from time to time furnish
  to the Commission will be incorporated by reference into, or otherwise be included in, this Registration Statement.
  Any statement contained in a document
  incorporated or deemed to be incorporated by reference herein shall be deemed to be modified or superseded for purposes of this
  Registration Statement to the extent that a statement contained herein or in any 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(b)(7) of the Delaware
  General Corporation Law, or the DGCL, provides that a Delaware corporation, in its certificate of incorporation, may limit the
  personal liability of a director to the corporation or its stockholders for monetary damages for breach of fiduciary duties as
  a director, except for liability for any:
  ·
  transaction from which the director derived an improper personal benefit;
  ·
  act or omission not in good faith or that involved intentional misconduct or a knowing violation
  of law;
  ·
  unlawful payment of dividends or redemption of shares; or
  ·
  breach of the director's duty of loyalty to the corporation or its stockholders.
  Section 145(a) of the DGCL provides,
  in general, that a Delaware corporation may indemnify any person who was or is a party, or is threatened to be made a party, to
  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 corporation) because that person is or was a director, officer, employee or agent of the
  corporation, or is or was serving at the request of the corporation as a director, officer, employee or agent of another corporation
  or other enterprise. The indemnity may include expenses (including attorneys' fees), judgments, fines and amounts paid in
  settlement actually and reasonably incurred by the person in connection with such action, so long as the person acted in good faith
  and in a manner he or she reasonably believed was in or not opposed to the corporation's best interests, and, with respect
  to any criminal action or proceeding, had no reasonable cause to believe his or her conduct was unlawful.
  Section 145(b) of the DGCL provides,
  in general, that a Delaware corporation may indemnify any person who was or is a party, or is threatened to be made a party, to
  any threatened, pending or completed action or suit by or in the right of the corporation to obtain a judgment in its favor because
  the person is or was a director, officer, employee or agent of the corporation, or is or was serving at the request of the corporation
  as a director, officer, employee or agent of another corporation or other enterprise. The indemnity may include expenses (including
  attorneys' fees) actually and reasonably incurred by the person in connection with the defense or settlement of such action,
  so long as the person acted in good faith and in a manner the person reasonably believed was in or not opposed to the corporation's
  best interests, except that no indemnification shall be permitted without judicial approval if a court has determined that the
  person is to be liable to the corporation with respect to such claim. Section 145(c) of the DGCL further provides that, if a present
  or former director or officer has been successful in defense of any action referred to above, the corporation must indemnify such
  officer or director against the expenses (including attorneys' fees) he or she actually and reasonably incurred in connection
  with such action.
  Section 145(g) of the DGCL provides,
  in general, that a corporation may purchase and maintain insurance on behalf of any person who is or was a director, officer, employee
  or agent of the corporation, or is or was serving at the request of the corporation as a director, officer, employee or agent of
  another corporation or other enterprise against any liability asserted against and incurred by such person, in any such capacity,
  or arising out of his or her status as such, whether or not the corporation could indemnify the person against such liability under
  Section 145 of the DGCL.
  The Company's Amended and Restated
  Certificate of Incorporation, as amended, eliminates the personal liability of its directors to the Company or its stockholders
  for monetary damages for breach of fiduciary duty as a director, with certain limited exceptions set forth therein. The Company's
  Amended and Restated Bylaws provide for the indemnification of its directors and officers to the fullest extent permitted by the
  DGCL.
  The Company maintains an insurance
  policy that covers certain liabilities of its directors and officers arising out of claims based on acts or omissions in their
  capacities as directors or officers.
  In addition, the Company has entered
  into separate indemnification agreements with its directors and officers, pursuant to which the Company has agreed to indemnify
  its directors and officers against certain liabilities and expenses incurred by such persons in connection with claims by reason
  of their being such a director or officer.
  Certain of the Company's non-employee
  directors may, through their relationships with their employers, also be insured and/or indemnified against certain liabilities
  incurred in their capacity as members of the Company's board of directors.
  The foregoing descriptions are only
  general summaries.
  Item 7.
  Exemption from Registration Claimed
  .
  Not applicable.
  Item 8.
  Exhibits
  .
  The exhibits below represent a complete list of exhibits filed or
  incorporated by reference as part of this Registration Statement.
  Exhibit No.
  Exhibit
  5.1
  Opinion of Polsinelli PC.
  10.1
  Humanigen, Inc. 2020 Omnibus Incentive Compensation Plan
  (incorporated by reference to Exhibit 10.1 to the Company's Current Report on Form 8-K filed on September 11, 2020 (File No. 001-35798)).
  23.1
  Consent of HORNE LLP.
  23.2
  Consent of Polsinelli PC (included in Exhibit 5.1).
  24.1
  Power of Attorney. Included on the signature page of the Registration Statement.
  Item 9.
  Undertakings
  .
  A. 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 of 1933;
  (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. Notwithstanding the foregoing, any increase or decrease in volume of securities offered (if the total dollar value of
  securities offered would not exceed that which was registered) and any deviation from the low or high end of the estimated maximum
  offering range may be reflected in the form of prospectus filed with the Commission pursuant to Rule 424(b) if, in the aggregate,
  the changes in volume and price represent no more than 20% change in the maximum aggregate offering price set forth in the "Calculation
  of Registration Fee" table in the effective Registration Statement.
  (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
  (A)(1)(i) and (A)(1)(ii) above 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 Securities Exchange Act of 1934 that are incorporated by reference in the Registration Statement.
  2. That, for the purpose of determining
  any liability under the Securities Act of 1933, each such post-effective amendment shall be deemed to be a new registration statement
  relating to the securities offered herein, 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.
  B. The undersigned Registrant hereby undertakes that,
  for purposes of determining any liability under the Securities Act of 1933, each filing of the Registrant's annual report
  pursuant to Section 13(a) or Section 15(d) of the Securities Exchange Act of 1934 (and, where applicable, each filing of an employee
  benefit plan's annual report pursuant to Section 15(d) of the Securities Exchange Act of 1934) that is incorporated by reference
  in the Registration Statement shall be deemed to be a new registration statement relating to the securities offered herein, and
  the offering of such securities at that time shall be deemed to be the initial bona fide offering thereof.
  C. Insofar as indemnification for liabilities arising
  under the Securities Act of 1933 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 of 1933 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 of 1933 and will be governed
  by the final adjudication of such issue.
  SIGNATURE
  Pursuant to the requirements of the
  Securities Act of 1933, 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 Burlingame, State of California on September 14, 2020.
  Humanigen, Inc.
  By:
  /s/ Cameron Durrant
  Cameron Durrant, M.D., MBA
  Chairman of the Board and Chief Executive Officer
  POWER OF ATTORNEY AND SIGNATURES
  Each person whose signature appears
  below constitutes and appoints Cameron Durrant, Timothy Morris and David Tousley, and each of them, his or her true and lawful
  attorneys-in-fact and agents, 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, without limitation, 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 Exchange Commission, under the Securities Act of 1933, 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, as fully to
  all intents and purposes as he or she might or could do in person, hereby ratifying and confirming all that each of said attorneys-in-fact
  and agents or their substitute or substitutes may lawfully do or cause to be done by virtue hereof.
  Pursuant to the requirements of the Securities Act of
  1933, this Registration Statement on Form S-8 has been signed by the following persons in the capacities and on the dates indicated.
  Signature
  Title
  Date
  /s/ Cameron Durrant
  Cameron Durrant, M.D., MBA
  Chairman of the Board and Chief Executive Officer
  (Principal Executive Officer)
  September 14, 2020
  /s/ Timothy Morris
  Timothy Morris, CPA
  Chief Operating Officer and Chief Financial Officer
  (Principal Financial Officer)
  September 14, 2020
  /s/ David Tousley
  David Tousley, MBA, CPA
  Chief Accounting and Administrative Officer,
  Corporate Secretary and Treasurer
  (Principal Accounting Officer)
  September 14, 2020
  /s/ Ronald Barliant
  Ronald Barliant, JD
  Director
  September 14, 2020
  /s/ Rainer Boehm
  Rainer Boehm, M.D.
  Director
  September 14, 2020
  /s/ Cheryl Buxton
  Cheryl Buxton
  Director
  September 14, 2020
  /s/ Robert G. Savage
  Robert G. Savage, MBA
  Director
  September 14, 2020