Exhibit 10.1


 


THE SECURITIES REPRESENTED HEREBY (THE
“SECURITIES”) HAVE NOT BEEN REGISTERED UNDER THE SECURITIES ACT OF 1933, AS AMENDED (THE “SECURITIES ACT”),
OR ANY STATE SECURITIES LAWS AND MAY NOT BE SOLD, ASSIGNED, TRANSFERRED, PLEDGED, ENCUMBERED, HYPOTHECATED, EXCHANGED OR OTHERWISE
DISPOSED OF UNLESS REGISTERED UNDER THE SECURITIES ACT AND UNDER APPLICABLE STATE SECURITIES LAWS OR THE COMPANY SHALL HAVE RECEIVED
AN OPINION OF COUNSEL FOR THE HOLDER, REASONABLY SATISFACTORY TO THE COMPANY AND ITS COUNSEL, THAT REGISTRATION OF SUCH SECURITIES
UNDER THE SECURITIES ACT AND UNDER THE PROVISIONS OF APPLICABLE STATE SECURITIES LAWS IS NOT REQUIRED. 


 


CONVERTIBLE PROMISSORY NOTE


 


	$[NUMBER]	[DATE]


 


 


For value received,
Humanigen, Inc., a Delaware corporation (the “Company”), promises to pay to [HOLDER NAME] (the “Holder”)
the principal sum of $[NUMBER] together with accrued and unpaid interest thereon, each due and payable on the date and in the manner
set forth below.


 


This convertible promissory
note (this “Note”) is issued as part of a series of similar convertible promissory notes (collectively,
the “Notes”) pursuant to the terms of that certain Convertible Note Purchase Agreement dated as of [DATE]
by and among the Company, Holder, and the other purchasers identified therein, as the same may be amended from time to time (the
“Agreement”). Capitalized terms used but not otherwise defined herein shall have the meanings ascribed
to them in the Agreement. This Note is an unsecured obligation of the Company.


 


1.       Repayment.
Unless otherwise converted as provided herein, all unpaid principal together with the unpaid and accrued interest payable hereunder
shall be due and payable on the date repayment is demanded by the Holder which may be any day on or after the earliest of (i) twenty-four
months from the date of this Note (the “Stated Maturity Date”), (ii) the occurrence of an Event of Default
(as described in Section 7 below), or (iii) the occurrence of a Liquidation Event (the earliest date of which being the “Maturity
Date”). “Liquidation Event” means (i) any event pursuant to which (A) any Person or Persons
acting as a group acquires all or substantially all of the assets of the Company by sale, exclusive license or otherwise, or (B)
any Person or Persons acting as a group (other than the equity holders of the Company existing as of the date hereof), whether
by merger, consolidation or otherwise, shall become the beneficial owner(s) of greater than an aggregate of 50% of the Company’s
outstanding voting equity interests (other than in connection with a Qualified Financing (as defined below) or Non-Qualified Financing
(as defined below)), or (ii) any dissolution or winding-up of the Company. This Note shall rank pari passu with each of
the other Notes such that all Notes shall rank equally and no payment will be made under any Note unless a pro rata payment is
simultaneously made under all Notes.


 


2.       Interest
Rate. The Company promises to pay simple interest on the outstanding principal amount hereof from the date hereof until payment
in full, which interest shall be payable at the rate of 7.5% per annum or the maximum rate permissible by law, whichever is less.
Interest shall be due and payable on the Maturity Date and shall be calculated on the basis of a 365-day year for the actual number
of days elapsed.


 






    	 	 	 



    	 



    

 


3.       Conversion.



 


(a)       Mandatory
Conversion Upon Qualified Financing. If the Company issues and sells its Equity Securities (as defined below) to investors
(the “Qualified Financing Investors”) on or before the Stated Maturity Date in any bona fide financing
transaction that results in gross proceeds to the Company of at least $10,000,000 (excluding conversion of this Note and other
indebtedness) (a “Qualified Financing”) or the Company consummates a reverse merger or similar transaction,
then the Company will give the Holder at least ten days’ prior written notice of the anticipated closing date of such Qualified
Financing or reverse merger, and the outstanding principal balance and any unpaid and accrued interest on this Note, together with
such additional amount of interest as would have been paid on this Note if held to the Stated Maturity Date (the “Conversion
Amount”), will automatically be converted, upon such closing date (and, in the case of a reverse merger, immediately
prior to the consummation of such reverse merger), into either, at the Holder’s option, (x) (A) in the case of a Qualified
Financing, such Equity Securities as the Holder would acquire if the Conversion Amount were invested directly in the Qualified
Financing on the same terms and conditions (including price) as given to the Qualified Financing Investors or (B) in the case of
a reverse merger, shares of Common Stock at the same price per share paid by the buyer in such transaction (which, in a stock for
stock deal, shall be based on the price per share used by the parties for purposes of setting the applicable exchange ratio), or
(y) Common Stock at a conversion price equal to $1.25 per share (subject to ratable adjustment for any stock split, stock dividend,
stock combination or other recapitalization occurring subsequent to the date of this Note), as each Holder shall elect and notify
the Company at least five days prior to the anticipated closing date of such Qualified Financing. For purposes of this Note, “Equity
Securities” shall mean Common Stock or any securities issued by the Company (other than convertible indebtedness)
and conferring the right to purchase Common Stock or that are convertible into or exercisable or exchangeable for (with or without
additional consideration) Common Stock, whether sold independently or as part of a unit of one or more securities issued by the
Company.


 


(b)       Optional
Conversion Upon Non-Qualified Financing. In the event that the Company issues and sells shares of its Equity Securities to
investors (the “Non-Qualified Financing Investors”) on or before the date of the repayment in full of
this Note in any bona fide financing transaction that is not a Qualified Financing (a “Non-Qualified
Financing”), then the Company will give the Holder at least ten days’ prior written notice of the anticipated
closing date of such Non-Qualified Financing and the Holder may elect to convert all, but not less than all, of the Conversion
Amount of the Notes held by such Holder, upon such closing date, into either (x) such Equity Securities as the Holder would acquire
if the Conversion Amount were invested directly in the Non-Qualified Financing on the same terms and conditions (including price)
as given to the Non-Qualified Financing Investors, or (y) Common Stock at a conversion price equal to $1.25 per share (subject
to ratable adjustment for any stock split, stock dividend, stock combination or other recapitalization occurring subsequent to
the date of this Note). In order to exercise the option to convert this Note pursuant to this Section 3(b), the Holder must notify
the Company of the Holder’s election to so convert at least five days prior to the anticipated closing date of the Non-Qualified
Financing.


 


(c)       Optional
Conversion Upon Liquidation Event. In the event that the Company enters into any agreement providing for, or publicly announces
the intention to consummate, a Liquidation Event prior to the conversion or repayment in full of this Note, (i) the Company will
give the Holder at least ten days’ prior written notice of the anticipated closing date of such Liquidation Event, and (ii)
the Holder may elect to convert, upon such closing date (and immediately prior to the consummation of such Liquidiation Event),
all, but not less than all, of the Conversion Amount into Common Stock at a conversion price equal to $1.25 per share (subject
to ratable adjustment for any stock split, stock dividend, stock combination or other recapitalization occurring subsequent to
the date of this Note). In order to exercise the option to convert the Notes pursuant to this Section 3(c), the Holder must notify
the Company of the Holder’s election to so convert or require payment at least five days prior to the anticipated closing
date of the Liquidation Event.


 






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(d)       Optional
Conversion Upon Collaboration Or Expiry Of Holding Period. Commencing on the earlier of (x) such time as the Company publicly
announces that it has entered into a definitive arrangement with an unaffiliated third party (a “Strategic Partner”)
pursuant to which, among other things, such Strategic Partner may agree to collaborate with the Company in conducting a clinical
study to assess the efficacy of the Company’s lenzilumab monoclonal antibody in reducing adverse effects from neurotoxicity
and cytokine release syndrome when used as a companion therapy in certain CAR-T cell therapies, or (y) the six-month anniversary
of the date of this Note, the Holder may elect to convert any portion of the outstanding principal amount of this Note, together
with (i) any unpaid and accrued interest on such principal amount to the date the Holder’s notice of the Holder’s intention
to convert is received by the Company (the “Notice Date”), and (ii) such additional amount of interest
as would have been paid on such principal amount from the Notice Date to the Stated Maturity Date, into Common Stock at a conversion
price equal to $1.25 per share (subject to ratable adjustment for any stock split, stock dividend, stock combination or other recapitalization
occurring subsequent to the date of this Note). In order to exercise the option to convert all or any portion of the principal
amount of this Note pursuant to this Section 3(d), the Holder shall notify the Company of the Holder’s election to so convert
in accordance with the provisions of Section 9 hereof, and shall specify in such notice the principal amount of this Note to be
converted and the date on which such conversion shall be effected.


 


(e)       No
fractional shares or units will be issued on conversion of this Note. If the Holder would otherwise be entitled to a fractional
share or unit, the Holder shall receive in lieu thereof a cash payment equal to the applicable per share or per unit price of the
Equity Securities or Common Stock into which the Conversion Amount is proposed to be converted, as applicable, multiplied by the
fraction of the share or unit the Holder would otherwise be entitled to receive. If conversion of this Note occurs pursuant to
Section 3(a) or Section 3(b), the Company shall use its commercially reasonable efforts to afford to the Holder the ability to
become a party to any agreement pursuant to which an investor in a Qualified Financing or Non-Qualified Financing, as the case
may be, may receive registration rights in respect of the Equity Securities issued by the Company in such transaction.


 


4.       Maturity.
If this Note has not been previously converted pursuant to Section 3 above, then, effective upon the Stated Maturity Date, the
Holder may elect to convert the Conversion Amount of the Notes into Common Stock at a conversion price equal to $1.25 per share
(subject to ratable adjustment for any stock split, stock dividend, stock combination or other recapitalization occurring subsequent
to the date of this Note). Any election to convert the Notes pursuant to this paragraph must be made in writing and delivered to
the Company at least five days prior to the Maturity Date. Unless this Note has been previously converted in accordance with the
terms of Section 3 above or pursuant to the preceding sentences of this Section 4, the entire outstanding principal balance and
all unpaid accrued interest shall become fully due and payable on the Stated Maturity Date.


 


5.       Expenses.
 In the event of any default hereunder, the Company shall pay all reasonable attorneys’ fees and court costs incurred
by the Holder in enforcing and collecting this Note.


 


6.       Prepayment.
The Company may not prepay this Note (including accrued interest), in whole or in part, prior to the Maturity Date without the
consent of the Holder.


 


7.       Default.
If there shall be any Event of Default (as defined below) hereunder, at the option and upon the declaration of the Holder and
upon written notice to the Company (which election and notice shall not be required in the case of an Event of Default under Section
7(c), 7(d) or 7(e)), this Note shall accelerate and all principal and unpaid accrued interest shall become due and payable. The
occurrence of any one or more of the following shall constitute an “Event of Default”:


 






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(a)       The
Company fails to pay timely any of the principal amount due under this Note on the date the same becomes due and payable or any
accrued interest or other amounts due under this Note on the date the same becomes due and payable;


 


(b)       The
Company shall default in its performance of any covenant under the Agreement or this Note, and such default is not cured by the
Company within 30 days after written notice thereof is given to the Company by the Holder;


 


(c)       The
Company files any petition or action for relief under any bankruptcy, reorganization, insolvency or moratorium law or any other
law for the relief of, or relating to, debtors, now or hereafter in effect, or makes any assignment for the benefit of creditors
or takes any corporate action in furtherance of any of the foregoing;


 


(d)       An
involuntary petition is filed against the Company (unless such petition is dismissed or discharged within 60 days) under any bankruptcy
statute now or hereafter in effect, or a custodian, receiver, trustee, assignee for the benefit of creditors (or other similar
official) is appointed to take possession, custody or control of any property of the Company;


 


(e)       A
liquidation, termination of existence or dissolution of the Company; or


 


(f)       Any
representation, warranty or statement of fact made by the Company in the Agreement, or any other agreement, schedule, confirmatory
assignment or otherwise in connection with the transactions contemplated hereby or thereby, shall when made or deemed made be false
or misleading in any material respect; provided, however, that such failure shall not result in an Event of Default to the extent
it is corrected by the Company within a period of 30 days after the Company’s receipt of written notice from the Holder specifying
such failure.


 


8.       Waiver.
The Company hereby waives demand, notice, presentment, protest and notice of dishonor.


 


9.       Notices.
All notices, requests, demands, consents, instructions or other communications required or permitted hereunder shall be in writing
and faxed, emailed, mailed or delivered to each party as follows: (i) if to the Holder, at the Holder’s address, email address
or facsimile number set forth in the Agreement, or at such other address, email address or facsimile number as the Holder shall
have furnished the Company in writing, or (ii) if to the Company, at the Company’s address, email address or facsimile number
set forth on the signature page to the Agreement, or at such other address, email address or facsimile number as the Company shall
have furnished to the Holder in writing. All such notices and communications will be deemed effectively given the earliest of (a)
when received, (b) when delivered personally, (c) one business day after being delivered by facsimile or email (with receipt of
appropriate confirmation), (d) one business day after being deposited with an overnight courier service of recognized standing
or (e) three days after being deposited in the U.S. mail, first class with postage prepaid.


 


10.       Governing
Law. This Note shall be governed by and construed under the internal laws of the State of New York, without giving effect to
conflicts of laws principles.


 


11.       Modification;
Waiver. Any term of this Note may be amended or waived with the written consent of the Company and the Holder. In
the event that the Company amends or otherwise modifies any other of the Notes, the Company shall give notice thereof to the Holder
and, upon request by the Holder, this Note shall be similarly amended or modified.


 






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12.       Powers
and Remedies Cumulative; Delay or Omission Not Waiver of Default. No right or remedy herein conferred upon or reserved to the
Holder is intended to be exclusive of any other right or remedy, and every right and remedy shall, to the extent permitted by law,
be cumulative and in addition to every other right and remedy given hereunder or now or hereafter existing at law or in equity
or otherwise. The assertion or employment of any right or remedy hereunder, or otherwise, shall not prevent the concurrent assertion
or employment of any other appropriate right or remedy. No delay or omission of the Holder to exercise any right or power accruing
upon any Event of Default occurring and continuing as aforesaid shall impair any such right or power or shall be construed to be
a waiver of any such Event of Default or an acquiescence therein; and every power and remedy given by this Note or by law may be
exercised from time to time, and as often as shall be deemed expedient, by the Holder.


 


13.       Transfer
Rights. The Holder may not transfer this Note to a third party without the prior written consent of the Company, not to be
unreasonably withheld, conditioned or delayed; provided, however, that the Holder shall have the right to transfer and assign this
Note without any consent of the Company to a Permitted Transferee (as defined below). Each new Note issued upon any transfer of
this Note shall bear a legend as to the applicable restrictions on transferability to ensure compliance with the Act, unless in
the opinion of counsel for the Company such legend is not required in order to ensure compliance with the Act. The Company may
issue stop transfer instructions to its Transfer Agent, if any, in connection with such restrictions. Subject to the foregoing,
transfers of this Note shall be registered upon registration books maintained for such purpose by or on behalf of the Company.
Prior to presentation of this Note for registration of transfer, the Company shall treat the registered holder hereof as the owner
and holder of this Note for the purpose of receiving all payments of principal and interest hereon and for all other purposes whatsoever,
whether or not this Note shall be overdue and the Company shall not be affected by notice to the contrary. “Permitted
Transferee” means, as to any Holder, any of the following: (i) if a natural person, his/her ancestors, descendants,
siblings, or spouse, any executor or administrator of his/her estate, or to a custodian, trustee (including a trustee of a voting
trust), executor, or other fiduciary primarily for the account of such Holder or his/her ancestors, descendants, siblings, or spouse,
whether step, in-law or adopted, and, in the case of any such trust or fiduciary, to the Holder who transferred this Note to such
trust or fiduciary, but only with respect to transfers made for bona fide estate planning purposes, either during his or her lifetime
or on death by will or intestacy; (ii) with respect to any Holder which is an entity, (A) the then-existing members, shareholders
or other investors in the Holder in connection with the dissolution or winding-up of the Holder, or (B) any Person in connection
with any consolidation or reorganization of the Holder directly or indirectly with or into one or more other investment vehicles;
(iii) any affiliate of the Holder (other than any investment portfolio company of the Holder that is an affiliate) which controls,
is controlled by or is under common control with the Holder; or (iv) any fund or entity managed or advised by Soundview Capital
Partners LP or any affiliate thereof.


 


14.       Most
Favored Nation Amendment Provisions. Prior to the conversion or payment in full of the Note, if the Company issues any indebtedness
which is convertible into the Company’s Equity Securities (“Subsequent Convertible Securities”),
the Company will promptly provide Holder with written notice thereof, together with a copy of all documentation relating to such
Subsequent Convertible Securities and, upon written request of Holder, any additional information related to such Subsequent Convertible
Securities as may be reasonably requested by Holder. Within 30 days after the Holder’s receipt of such information,
if the Holder determines that the terms of the Subsequent Convertible Securities are preferable to the terms of the Note, Holder
will notify the Company in writing. Promptly after receipt of such written notice from the Holder, the Company agrees to amend
and restate the Note to be identical to the instruments evidencing the Subsequent Convertible Securities and any purchase documents
related thereto.


 






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15.       Assignment
by the Issuer. Neither this Note nor any of the rights, interests or obligations hereunder may be assigned, in whole or in
part, by the Company, without the prior written consent of the Holder.


 


16.       Successors
and Assigns. Subject to the restrictions on transfer provided herein, the rights and obligations of the Company and the Holder
shall be binding upon and benefit the respective successors, assigns, heirs, administrators and transferees of the Company or the
Holder, as applicable.


 


ORAL AGREEMENTS OR
COMMITMENTS TO LOAN MONEY, EXTEND CREDIT OR TO FORBEAR FROM ENFORCING REPAYMENT OF A DEBT INCLUDING PROMISES TO EXTEND OR RENEW
SUCH DEBT ARE NOT ENFORCEABLE. TO PROTECT THE COMPANY AND THE HOLDER FROM MISUNDERSTANDING OR DISAPPOINTMENT, ANY AGREEMENTS WE
REACH COVERING SUCH MATTERS ARE CONTAINED IN THIS WRITING, WHICH IS THE COMPLETE AND EXCLUSIVE STATEMENT OF THE AGREEMENT BETWEEN
US, EXCEPT AS WE MAY LATER AGREE IN WRITING TO MODIFY IT.


 


[Remainder of Page
Intentionally Left Blank]


 






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IN WITNESS WHEREOF,
the Company has caused this Convertible Promissory Note to be issued as of the date first set forth above.


 


	 	
        COMPANY:

         

        HUMANIGEN, INC.

	 	 	 
	 	 	 
	 	 	 
	 	By:	_/s/ Cameron Durrant
	 	 	
        Name: Dr. Cameron Durrant

        Title: Chief Executive Officer 



 


 


 


[Signature Page to Convertible Promissory
Note]