Exhibit 10.24


 


THIS AMENDED AND RESTATED PROMISSORY NOTE
(“NOTE”) HAS NOT BEEN REGISTERED UNDER THE SECURITIES ACT OF 1933, AS AMENDED (THE “SECURITIES ACT”).
THIS NOTE HAS BEEN ACQUIRED FOR INVESTMENT ONLY AND MAY NOT BE SOLD, TRANSFERRED OR ASSIGNED IN THE ABSENCE OF REGISTRATION OF
THE RESALE THEREOF UNDER THE SECURITIES ACT OR AN OPINION OF COUNSEL REASONABLY SATISFACTORY IN FORM, SCOPE AND SUBSTANCE TO THE
ISSUER THAT SUCH REGISTRATION IS NOT REQUIRED.


 


AMENDED AND RESTATED PROMISSORY NOTE


 


	Principal Amount: $371,178.00	Original Issuance Date: March 15, 2019
	 	
        Reissuance Date: September 8, 2020

        Effective Date: The date of the Consummation

        of the Business Combination (as defined)



 


This Amended and Restated
Promissory Note (this “Note”) amends and restates in its entirety that certain Promissory Note dated March 15,
2019 in the original principal amount of $1,087,031.00 that was issued by KBL Merger Corp. IV, a Delaware corporation (“Maker”),
to KBL IV Sponsor LLC (including its successors or assigns, “Payee”; and such original promissory note, the
“Original Note”). The Original Note is being amended and restated as set forth herein to, among other things,
reflect that the principal amount of the Original Note has been reduced from $1,087,031.00 to $371,178.


 


Effective the Effective
Date, Maker hereby promises to pay to the order of Payee the principal sum of Three Hundred Seventy-One Thousand One Hundred Seventy-Eight
Dollars ($371,178.00), in lawful money of the United States of America, on the terms and conditions described below.


 


1. Repayment. The
principal balance of this Note shall be due and payable upon the consummation of the purchase and sale of the Company’s Series
A Convertible Preferred Stock at the “Second Closing” contemplated under that certain Securities Purchase Agreement
(as amended or otherwise modified, the “Dominion Purchase Agreement”) dated as of June 12, 2020 among Maker,
the purchasers identified on the signature pages thereto, and Dominion Capital LLC as purchaser agent (such event, the “Preferred
Closing”), and the principal balance of this Note shall be paid out of the proceeds to Maker of the Preferred Closing
(with it being understood and agreed that this Note shall participate on a pro rata basis with any other payments scheduled to
be made out of the proceeds of the Preferred Closing) using the proceeds to Maker of the Preferred Closing. All payments on this
Note shall be made by check or wire transfer of immediately available funds or as otherwise agreed by Payee to such account as
Payee may from time to time designate by written notice in accordance with the provisions of this Note.


 


2. Interest. This
Note shall be non-interest bearing.


 


3. Application of
Payments. All payments rightfully received by Payee pursuant to this Note shall be applied first to the 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.


 


4. Events of Default.
The following shall constitute an event of default (“Event of Default”):


 


(a) Failure to
Make Required Payments. Failure by Maker to pay the principal amount pursuant to 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 bankruptcy, insolvency, reorganization, rehabilitation or other similar law (“Bankruptcy Laws”),
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, or the taking of corporate action
by Maker in furtherance of any of the foregoing.


 



     


    	 



    




 


(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 any applicable Bankruptcy Laws, 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.


 


5. Remedies.
Subject to Section 15:


 


(a) Upon the occurrence
of an Event of Default specified in Section 4(a) hereof, Payee may, by written notice to Maker, declare this Note to be due immediately
and payable, whereupon the unpaid principal amount of this Note and all other amounts payable hereunder 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 4(b) and 4(c) hereof, the unpaid principal balance of this Note and all other amounts
payable hereunder shall automatically and immediately become due and payable, in all cases without any action on the part of Payee.


 


(c) In the event that
Maker does not make the payments to Payee as (and in the amounts) required under Section 1 as a result of the Preferred Closing,
or (and assuming that Maker has made the payments to Payee as (and in the amounts) required under Section 1 as a result of the
Preferred Closing) if Maker does not repay the unpaid principal balance of this Note in full to Payee on or prior to the second
business day following the consummation of a capital raising transaction following the closing of Maker’s initial business
combination (as described in the prospectus contained in Maker’s registration statement on Form S-1 filed with the Securities
and Exchange Commission in connection with Maker’s initial public offering) yielding aggregate gross proceeds to Maker in
an amount equal to or in excess of $5,000,000, then Maker shall pay to Payee as partial liquidated damages and not as a penalty
an additional amount equal to $2,000 per day for each additional day until this Note is paid in full; provided, that the
maximum liquidated damages shall be the principal balance of this Note that remains unpaid upon the occurrence of the first applicable
repayment event described in this Section 5(c)).


 


6. Waivers. Maker
and all 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 this 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 or personal property 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.


 


7. 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 additional makers, endorsers, guarantors,
or sureties may become parties hereto without notice to Maker or affecting Maker’s liability hereunder.


 


8. Notices. Any
notice called for hereunder shall be deemed properly given if (i) sent by certified mail, return receipt requested, (ii) personally
delivered, (iii) dispatched by any form of private or governmental express mail or delivery service providing receipted delivery,
(iv) sent by facsimile or (v) sent by e-mail, to the following addresses or to such other address as either party may designate
by notice in accordance with this Section:


 






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	If to Maker, to:	 	with a copy (which will not constitute notice) to:
	KBL Merger Corp. IV	 	Pryor Cashman LLP
	30 Park Place, Suite 45E	 	7 Times Square
	New York, NY 10007	 	New York, New York 10036
	Attn: Marlene Krauss M.D., CEO	 	Attn: 	M. Ali Panjwani, Esq.
	 	 	 	 
	Email: mkrauss@kblvc.com	 	Telephone No.: (212) 326-4100
	 	 	Email: 	 ali.panjwani@pryorcashman.com
	 	 	 


 


	If to Payee, to:	 	with a copy (which will not constitute notice) to:
	 	 	 
	KBL Sponsor IV LLC	 	Pryor Cashman LLP
	30 Park Place, Suite 45E	 	7 Times Square
	New York, NY 10007	 	New York, New York 10036
	Attn: Marlene Krauss M.D., Managing Member	 	Attn: 	M. Ali Panjwani, Esq.
	 	 	 	 
	Email: mkrauss@kblvc.com	 	Telephone No.: (212) 326-4100
	 	 	Email: 	 ali.panjwani@pryorcashman.com
	 	 	 


 


Notice shall be deemed given on the earlier
of (i) actual receipt by the receiving party, (ii) the date shown on a facsimile transmission confirmation, (iii) the date on which
an e-mail transmission was received by the receiving party’s on-line access provider (iv) the date reflected on a signed
delivery receipt, or (vi) two (2) business days following tender of delivery or dispatch by express mail or delivery service.


 


9. Governing
Law; Venue, Jury Trial Waiver. This Note shall be construed and enforced in accordance with the laws of the State of New York,
without regard to the conflict of laws provisions thereof. Any legal suit, action or proceeding arising out of or relating to this
Note shall be instituted exclusively in the state or federal courts of the State of New York (and any appellate courts thereof).
EACH PARTY HERETO HEREBY IRREVOCABLY WAIVES ANY AND ALL RIGHT TO TRIAL BY JURY IN ANY LEGAL PROCEEDING ARISING OUT OF OR RELATED
TO THIS NOTE OR ANY OBLIGATIONS HEREUNDER.


 


10.
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.


 


11.
Trust Waiver. Notwithstanding anything herein to the contrary, Payee hereby waives any and all right, title, interest or claim
of any kind (a “Claim”) in or to any distribution of or from the trust account (the “Trust Account”)
established by Maker in which the proceeds of the IPO (including without limitation overallotment securities sold by Maker’s
underwriter) and the proceeds of the sale of the units issued in the private placement that occurred in connection with the IPO,
as described in greater detail in the registration statement and prospectus filed in connection with the IPO, were deposited, and
hereby agrees not to seek recourse, reimbursement, payment or satisfaction for any Claim against the Trust Account or distributions
therefrom to Maker’s public stockholders for any reason whatsoever; provided, however, that upon the consummation of the
Business Combination, Maker shall repay the principal balance of this Note out of the proceeds released to Maker from the Trust
Account.


 


12.
Entire Agreement; Amendment; Waiver. This Note constitutes the entire agreement between the parties with respect to the subject
matter hereof and referenced herein, and supersedes and terminates any prior agreements between the parties (written or oral) with
respect to the subject matter hereof, including, without limitation, the Original Note. Any amendment or modification to, or waiver
of any provision of, this Note may be made with, and only with, the written consent of Maker and Payee.


 






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13.
Assignment. No assignment or transfer of this Note or any rights or obligations hereunder may be made by any party hereto (by
operation of law or otherwise) without the prior written consent of the other party hereto and any attempted assignment without
the required consent shall be void; provided, however, that the foregoing shall not apply to an affiliate of Payee who agrees
to be bound to the terms of this Note.


 


14.
Miscellaneous. Each right, power and remedy of Payee provided for in this Note or now or hereafter existing at law or in equity
or by statute or otherwise shall be cumulative and concurrent and shall be in addition to every other such right, power or remedy.
This Note may be executed in multiple counterparts, including without limitation by facsimile, pdf or other electronic document
transmission, each of which shall be deemed an original and all of which together shall constitute one and the same instrument.
When a reference is made in this Note to a Section, such reference shall be to a Section of or to this Note unless otherwise indicated.
Unless the context requires otherwise, the terms “hereof,” “herein,” “hereby,” “hereto”
and derivative or similar words in this Note refer to this entire Note. Unless the context requires otherwise, words in this Note
using the singular or plural number also include the plural or singular number, respectively, and the use of any gender herein
shall be deemed to include the other genders. References in this Note to “dollars”, “Dollars” or “$”
are to U.S. dollars. This Note was prepared jointly by the parties and no rule that it be construed against the drafter will have
any application in its construction or interpretation. For purposes of this Note, the term “business day” shall mean
any day that is not a Saturday, Sunday or any other day on which banks are required or authorized by law to be closed in New York,
New York.


 


15. Subordination.
Reference is made to the Dominion Purchase Agreement and the Transaction Documents (as such term is defined in the Dominion Purchase
Agreement) executed and delivered in connection therewith. Upon the occurrence and continuance of an Event of Default (as such
term is defined in the applicable Transaction Document), and until Maker’s obligations to the secured parties under the Transaction
Documents have been satisfied in full, Maker’s obligations under this Note shall be second and subordinate to the rights
of such secured parties; provided, that the foregoing shall not in any way limit the obligation of Maker to repay this Note
in full, and to make the payments due hereunder to Payee in the absence of an Event of Default under the Transaction Documents.


 


[Signature Page Follows]


 




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IN WITNESS WHEREOF,
Maker, intending to be legally bound hereby, has caused this Amended and Restated Promissory Note to be duly executed by the
undersigned as of this 8th day of September, 2020.


 


	 	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 date first
set forth above:


 


	
        

        KBL SPONSOR IV LLC
	 
	 	 
	By:	/s/ Marlene Krauss, M.D.	 
	Name: 	Marlene Krauss, M.D.	 
	Title:	Managing Member	 


 


 


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