Exhibit 10.16


 


PROMISSORY NOTE


 


	Principal:$107,975.00	September 30, 2019


  


KBL Merger Corp. IV,
a Delaware corporation (“Maker”), promises to pay to the order of CannBioRx Life Sciences Corp., a Delaware
corporation (“Payee”), the principal sum of $107,975.00 (the “Principal Amount”)
in lawful money of the United States of America, on the terms and conditions described below. Capitalized terms used but not defined
in this promissory note (this “Note”) shall have the meanings ascribed to them in that certain Business
Combination Agreement (the “Business Combination Agreement”) by and among Maker, Payee, Katexco Pharmaceuticals
Corp., a British Columbia corporation, CannBioRex Pharmaceuticals Corp., a British Columbia corporation, 180 Therapeutics L.P.,
a Delaware limited partnership, KBL Merger Sub, Inc., a Delaware corporation, and Lawrence Pemble, in his capacity as the stockholder
representative. 


 


1. Principal.
The principal balance of this Note shall be payable on the earlier of (i) consummation of Maker’s Business Combination (whether
pursuant to the Business Combination Agreement or otherwise) and (ii) the liquidation of Maker in the event it does not consummate
a Business Combination. Maker hereby agrees that upon the consummation of an Alternative Business Combination pursuant to Section
7.3(a)(i) of the Business Combination Agreement, in addition to the repayment of the principal amount of this Note in accordance
with this Section 1, it will use its reasonable efforts to cause the Sponsor to comply with its obligations under Section 7(a)(i)
of the Business Combination Agreement to cause the Founder Shares Escrow Agent to transfer to Tyche Capital LLC a number of Escrowed
Founder Shares equal in value to three times the amount of the Covered Expense Loans, with each Escrowed Founder Share valued at
the Per Share Redemption Price (subject to equitable adjustment for stock splits, stock dividends, share exchanges, etc.).


 


2. Required Prepayment.
In the event that the Business Combination has not been consummated by the later of (a) the third Automatic Extension or (b) the
Additional Extension, as applicable, then promptly (but in any event within three Business Days) thereafter, Maker will use any
remaining funds in escrow with the Expense Escrow Agent to prepay the balance of this Note.


 


3. Interest.
No interest shall accrue on the unpaid principal balance of this Note.


 


4.  Application
of Payments. All payments shall be applied first to payment in full of any costs incurred in the collection of any sum due
under this Note, including (without limitation) reasonable attorneys’ fees, then to the payment in full of any late charges
and finally to the reduction of the unpaid principal balance of this Note.


 


5. Events of Default.
The following shall constitute Events of Default:


 


(a) Failure to Make
Required Payments. Failure by Maker to pay the principal of this Note within five (5) Business Days following the date when
due.


 


(b) Voluntary Bankruptcy,
Etc. The commencement by Maker of a voluntary case under the Federal Bankruptcy Code, as now constituted or hereafter amended,
or any other applicable federal or state bankruptcy, insolvency, reorganization, rehabilitation or other similar law, or the consent
by it to the appointment of or taking possession by a receiver, liquidator, assignee, trustee, custodian, sequestrator (or other
similar official) of Maker or for any substantial part of its property, or the making by it of any assignment for the benefit of
creditors, or the failure of Maker generally to pay its debts as such debts become due.


 






     


     


    

 


(c) Involuntary Bankruptcy,
Etc. The entry of a decree or order for relief by a court having jurisdiction in the premises in respect of Maker in an involuntary
case under the Federal Bankruptcy Code, as now or hereafter constituted, or any other applicable federal or state bankruptcy, insolvency
or other similar law, or appointing a receiver, liquidator, assignee, custodian, trustee, sequestrator (or similar official) of
Maker or for any substantial part of its property, or ordering the winding-up or liquidation of its affairs, and the continuance
of any such decree or order unstayed and in effect for a period of 60 consecutive days.


  


6. Remedies.


 


(a) Upon the occurrence
of an Event of Default specified in Section 5(a), Payee may, by written notice to Maker, declare this Note to be due and
payable, whereupon the principal amount of this Note, and all other amounts payable thereunder, shall become immediately due and
payable without presentment, demand, protest or other notice of any kind, all of which are hereby expressly waived, anything contained
herein or in the documents evidencing the same to the contrary notwithstanding.


 


(b) Upon the occurrence
of an Event of Default specified in Sections 5(b) and 5(c), the unpaid principal balance of, and all other sums payable with regard
to, this Note shall automatically and immediately become due and payable, in all cases without any action on the part of Payee.


 


7.  Waivers.
Maker and any endorsers and guarantors of, and sureties for, this Note waive presentment for payment, demand, notice of dishonor,
protest, and notice of protest with regard to the Note, all errors, defects and imperfections in any proceedings instituted by
Payee under the terms of this Note, and all benefits that might accrue to Maker by virtue of any present or future laws exempting
any property, real or personal, or any part of the proceeds arising from any sale of any such property, from attachment, levy or
sale under execution, or providing for any stay of execution, exemption from civil process, or extension of time for payment; and
Maker agrees that any real estate that may be levied upon pursuant to a judgment obtained by virtue hereof, on any writ of execution
issued hereon, may be sold upon any such writ in whole or in part in any order desired by Payee.


 


8. Unconditional
Liability. Maker hereby waives all notices in connection with the delivery, acceptance, performance, default, or enforcement
of the payment of this Note, and agrees that its liability shall be unconditional, without regard to the liability of any other
party, and shall not be affected in any manner by any indulgence, extension of time, renewal, waiver or modification granted or
consented to by Payee, and consents to any and all extensions of time, renewals, waivers, or modifications that may be granted
by Payee with respect to the payment or other provisions of this Note, and agrees that any additional makers, endorsers, guarantors,
or sureties may become parties hereto without notice to them or affecting their liability hereunder.


 


9. Notices.
Any notice called for hereunder shall be delivered in the manner set forth in Section 9.3 of the Business Combination Agreement.


 


10. Construction;
Venue. This Note shall be construed and enforced in accordance with the domestic, internal law, but not the law of conflict
of laws, of the State of New York. Any action, claim, suit or other legal proceeding relating to this Note shall be brought exclusively
in the state or federal courts located in New York County, State of New York (or any appellate courts therefrom). The parties expressly
waive any objection based on personal jurisdiction, venue or forum non conveniens.


 


11. Severability.
Any provision contained in this Note which is prohibited or unenforceable in any jurisdiction shall, as to such jurisdiction, be
ineffective to the extent of such prohibition or unenforceability without invalidating the remaining provisions hereof, and any
such prohibition or unenforceability in any jurisdiction shall not invalidate or render unenforceable such provision in any other
jurisdiction.


 






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12. Miscellaneous.
This Note will not be assignable or transferable by either Maker or Payee without the prior written consent of the other, and any
purported assignment or transfer without such consent shall be null and void ab initio. This Note, together with the Business Combination
Agreement, constitutes the full and entire understanding and agreement between the parties with regard to the subject matter hereof
and supersedes all prior understandings or agreements with respect thereto. No amendments or modifications of or changes to this
Note or waiver of the terms and conditions hereof will be binding upon Maker or Payee, unless approved in writing and signed by
both Maker and Payee.


 


13. Trust Fund Waiver.
Payee hereby acknowledges that the waiver against Maker’s Trust Account (and distributions therefrom) contained in Section
9.18 of the Business Combination Agreement continues in full force and effect and will apply to this Note and Maker’s obligations
hereunder.


 


[Signature Page Follows]


 




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IN WITNESS WHEREOF,
Maker, intending to be legally bound hereby, has caused this Note to be duly executed the day and year first above written.


 


	 	KBL Merger Corp. IV
	 	 	 
	 	By:	/s/ Marlene Krauss, M.D.
	 	Name:   	Marlene Krauss, M.D.
	 	Title: 	Chief Executive Officer


 


Acknowledged and agreed effective as
of the day and year first written above:


 


	CannBIORX
    LIFE SCIENCES CORP.	 
	 	 
	By:	/s/
    Prof. Sir Marc Feldmann	 
	Name:  	Prof. Sir Marc Feldmann	 
	Title:	Chairman	 


 


[Signature Page to Operating Expenses
Promissory Note]