Document:

Exhibit 10.20

 

NOTE
PURCHASE AGREEMENT

 

This Note Purchase
Agreement (this “Agreement”) is made and entered into as of August 29, 2020, by and among Reviva
Pharmaceuticals, Inc., a Delaware corporation (the “Company”), and the parties identified on the
signature pages hereto (each individually an “Investor” and collectively the “Investors”),
and shall become effective upon the consummation of the SPAC Merger (as defined herein).

 

RECITALS

 

Whereas,
the Company has entered into an Agreement and Plan of Merger, dated as of July 20, 2020 (as it may be amended, the “Merger
Agreement”), among Tenzing Acquisition Corp, a company incorporated in the British Virgin Islands (together with
its successors, the “SPAC Purchaser”), Tenzing Merger Subsidiary Inc., a Delaware corporation and a wholly-owned
subsidiary of the Purchaser (“SPAC Merger Sub”), the Company, and the other parties named therein, pursuant
to which Merger Sub would merge with and into the Company, with the Company continuing as the surviving entity, and the stockholders
of the Company will receive equity securities of SPAC Purchaser (the “SPAC Shares”) in exchange for their
shares of capital stock of the Company (the “SPAC Merger”) in accordance with the terms of the Merger
Agreement; and

 

Whereas,
the closing of the SPAC Merger is conditioned upon the satisfaction of that certain Agreed Judgment, issued in the District
Court for the 190th Judicial District, Harris County, Texas, and signed January 3, 2020, in favor of Ramachandra
Malya against the Company (the “Judgment”); and

 

Whereas,
the Company currently requires funds to satisfy the Judgment and to help finance its operations; and

 

Whereas,
the Investors are willing to advance funds to the Company, in an aggregate principal amount not to exceed Two Million Dollars ($2,000,000.00),
for the purpose of satisfying the Judgment and financing the Company’s operations in exchange for the issuance to them of
certain convertible promissory notes evidencing the Company’s obligation to repay the Investors’ loans of the advanced
funds, as provided in this Agreement.

 

Now,
Therefore, the parties hereby agree as follows:

 

1.            PURCHASE
AND SALE OF NOTES.

 

1.1            Note
Purchase. Subject to the terms and conditions of this Agreement, the Company agrees
to sell to each Investor, and each Investor severally agrees to purchase from the Company, a Convertible Promissory Note, in a
principal amount of not less than Fifty Thousand Dollars ($50,000.00), in the form attached to this Agreement as Exhibit A
(each individually a “Note” and collectively the “Notes”) in the principal
amount set forth on such Investor’s signature page hereto. This Agreement, all of the Notes and any document entered
into, executed or delivered under or in connection with, or for the purpose of amending, any of such documents are collectively
hereinafter referred to as the “Financing Documents.”

 

    

     

    

 

1.2            [Intentionally
Omitted.]

 

1.3            [Intentionally
Omitted.]

 

2.            CLOSING.

 

2.1            The
Closing. The purchase and sale of the Notes will take place at the offices of Lowenstein
Sandler LLP, One Lowenstein Drive, Roseland, New Jersey 07068, on the date of, and immediately prior to, the SPAC Merger (which
time and place are referred to as the “Closing”); provided, however, that the Closing must
occur prior to the Outside Date (as defined in the Merger Agreement). The Closing is contingent upon the substantially concurrent
consummation of the SPAC Merger. Upon not less than five (5) Business Days’ written notice from (or on behalf of) the
Company to the undersigned (the “Closing Notice”), which Closing Notice shall contain the Company’s wire
instructions for the Company’s bank account in which the funds shall be escrowed, that the Company reasonably expects all
conditions to the closing of the SPAC Merger to be satisfied on a date that is not less than five (5) business days from the
date of the Closing Notice, the undersigned shall deliver to the Company, at least two (2) business days prior to the anticipated
closing date specified in the Closing Notice (the “Closing Date”), the amount set forth on such Investor’s
signature page hereto by wire transfer of United States dollars in immediately available funds to the account specified by
the Company in the Closing Notice. Immediately prior to the Closing, the escrowed funds shall automatically be released to the
Company. At the Closing, the Company will deliver to each Investor a duly executed Note in the principal amount set forth on such
Investor’s signature page hereto. In the event the Closing does not occur on or prior to the Outside Date, any escrowed
funds delivered by the Investor to the Company shall be returned to the Investor within five (5) Business Days of the Outside
Date.

 

2.2            [Intentionally
Omitted.]

 

3.            REPRESENTATIONS
AND WARRANTIES OF THE COMPANY. The Company hereby represents and warrants to
each Investor that, except as set forth in the Schedule of Exceptions (the “Schedule of Exceptions”)
attached to this Agreement as Exhibit B, the statements in the following paragraphs of this Section 3 are all
true and complete as of immediately prior to the Closing:

 

3.1            Organization,
Good Standing and Qualification. The Company has been duly incorporated and organized,
and is validly existing in good standing, under the laws of the State of Delaware. The Company has the corporate power and authority
to own and operate its properties and assets and to carry on its business as currently conducted and as presently proposed to be
conducted.

 

3.2            Due
Authorization. All corporate action on the part of the Company’s board of directors
and stockholders necessary for the authorization, execution, delivery of, and the performance of all obligations of the Company
under, the Financing Documents has been taken or will be taken prior to the Closing. This Agreement constitutes, and the other
Financing Documents that constitute agreements of the Company when executed and delivered by the Company will constitute, valid
and legally binding obligations of the Company, enforceable against the Company in accordance with their respective terms, except
as may be limited by (i) applicable bankruptcy, insolvency, reorganization or other laws of general application relating to
or affecting the enforcement of creditors’ rights generally and (ii) the effect of rules of law governing the availability
of equitable remedies.

 

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3.3            Corporate
Power. The Company has the corporate power and authority to execute and deliver the
Financing Documents to which it is a signatory, to issue to the Investors the Notes to be purchased by the Investors hereunder
and to carry out and perform all its obligations under the Financing Documents. No direct or indirect consent, approval, authorization
or similar item is required to be obtained by the Company to enter into the Financing Documents to which it is a party and to perform
or undertake any of the transactions contemplated pursuant to the Financing Documents to which it is a party.

 

3.4            Valid
Issuance.

 

(a)            The
Notes and the Common Stock issuable upon conversion of the Notes, when issued, sold and delivered in accordance with the terms
of this Agreement and the Notes, for the consideration provided for herein and therein, will be duly and validly issued, fully
paid and nonassessable.

 

(b)            Based
in part on the representations made by the Investors in Section 4 hereof, the offer and sale of the Notes solely to the Investors
in accordance with this Agreement (assuming no change in currently applicable law or in the Company’s Certificate of Incorporation
in effect as of immediately prior to the Closing, no transfer of Notes by any Investor and no commission or other remuneration
is paid or given, directly or indirectly, for soliciting the issuance of Common Stock upon conversion of the Notes), and the issuance
of the Common Stock will be exempt from the registration and prospectus delivery requirements of the U.S. Securities Act of 1933,
as amended (the “Securities Act”), and the securities registration and qualification requirements of
the currently effective provisions of the securities laws of the states in which the Investors are resident based upon their addresses
as set forth on their respective signature pages hereto.

 

3.5            Capitalization.
The capitalization of the Company immediately prior to the Closing consists of the following:

 

(a)            Common
Stock. A total of Thirty Five Million (35,000,000) authorized shares of the Company’s Common Stock, par value $0.0001
per share (the “Common Stock”), of which Eighteen Million One Hundred Eighty Thousand Seven Hundred Forty-Eight
(18,180,748) shares are issued and outstanding.

 

(b)            Preferred
Stock. A total of Thirteen Million Six Hundred Twenty Five Thousand Two Hundred Thirty Seven (13,625,237) authorized shares
of Preferred Stock, of which Six Hundred Twenty Five Thousand Two Hundred Thirty-Seven (625,237) shares are designated as Series 1
Preferred Stock, $0.0001 par value per share, all of which are issued and outstanding; One Million Two Hundred Forty-Five Thousand
Eight Hundred Eighty-Nine (1,245,889) shares are designated as Series 2 Preferred Stock, $0.0001 par value per share, all
of which are issued and outstanding; Nine Hundred Fifty-One Thousand Seven Hundred Sixty-One (951,761) shares are designated as
Series 3 Preferred Stock, all of which are issued and outstanding; Five Million (5,000,000) shares are designated as Series 4
Preferred Stock, $0.0001 par value per share, One Million Twenty Nine Thousand Nine Hundred Ninety Four (1,029,994) of which are
issued and outstanding; and Five Million Eight Hundred Two Thousand Three Hundred Fifty (5,802,350) shares are undesignated.

 

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(c)            Reserved
Shares. Except for (i) the Three Million (3,000,000) shares of Common Stock reserved for issuance under the Company’s
2006 Equity Incentive Plan (the “Plan”) pursuant to which Four Hundred and Thirty Thousand (430,000)
shares are outstanding; (ii) Thirty Eight Thousand One Hundred and Ninety Nine (38,199) shares of Common Stock issuable upon
the exercise of outstanding warrants; (iii) conversion rights of the Series 1 Preferred Stock, Series 2 Preferred
Stock, Series 3 Preferred Stock, and Series 4 Preferred Stock, (iv) conversion rights in connection the Company’s
outstanding 2016 8% Convertible Promissory Notes with an aggregate principal balance of $3,490,088.00, inclusive of certain note
conversion shares issuable upon a conversion event, (v) conversion and stock issuance rights in connection with the Company’s
outstanding 2018 8% Convertible Promissory Notes with an aggregate principal balance of $275,000.00, inclusive of certain note
conversion shares issuable upon a conversion event, certain warrant issuances upon a conversion event, and the issuance of Eighty
Two Thousand Five Hundred (82,500) shares of Common Stock upon a conversion event, (vi) conversion and stock issuance rights
in connection with the Company’s outstanding 2020 8% Convertible Promissory Notes with an aggregate principal balance of
$610,000.00, inclusive of certain note conversion shares issuable upon a conversion event, certain warrant issuances upon a conversion
event, and the issuance of One Hundred and Ten Thousand (110,000) shares of Common Stock upon a conversion event and (vii) the
rights of first refusal held by the Company to repurchase any shares of its stock that may be issued under the Plan or under that
certain Founder’s Restricted Stock Purchase Agreement by and between the Company and Laxminarayan Bhat dated as of May 2,
2006, there are no outstanding options, warrants, conversion rights, preemptive rights, rights of first refusal or agreements for
the purchase or acquisition of any shares of the Company’s capital stock or any securities convertible into or ultimately
exchangeable or exercisable for any shares of the Company’s capital stock.

 

(d)            The
outstanding shares of the capital stock of the Company are duly authorized and validly issued, fully paid and nonassessable.

 

4.            REPRESENTATIONS,
WARRANTIES AND CERTAIN AGREEMENTS OF INVESTORS. Each Investor hereby, severally
and not jointly, represents and warrants to, and agrees with the Company that:

 

4.1            Authorization.
This Agreement constitutes, and the other Financing Documents that constitute agreements of the Investor when executed and delivered
by the Investor will constitute, such Investor’s valid and legally binding obligations, enforceable against such Investor
in accordance with their terms, except as may be limited by (i) applicable bankruptcy, insolvency, reorganization or other
laws of general application relating to or affecting the enforcement of creditors’ rights generally and (ii) the effect
of rules of law governing the availability of equitable remedies. Each Investor represents and warrants to the Company that
such Investor has full power and authority to enter into this Agreement and acquire such Investor’s Note. There are no actions,
suits, proceedings or investigations pending against such Investor or such Investor's assets before any court or governmental agency
(nor is there any threat thereof) that would impair in any way such Investor's ability to enter into and fully perform its commitments
and obligations under this Agreement or the transactions contemplated hereby.

 

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4.2            Purchase
for Own Account. The Notes and Common Stock issuable upon conversion of the Notes
(collectively, the “Securities”) will be acquired for investment for such Investor’s own account,
not as a nominee or agent, and not with a view to the public resale or distribution thereof within the meaning of the Securities
Act, and such Investor has no present intention of selling, granting any participation in, or otherwise distributing the same.

 

4.3            No
Solicitation. At no time was such Investor presented with or solicited by any publicly
issued or circulated newspaper, mail, radio, television or other form of general advertising or solicitation in connection with
the offer, sale and purchase of the Securities.

 

4.4            Reliance
on Exemptions. Such Investor understands that the Securities are being offered and
sold to it in reliance on specific exemptions from the registration requirements of United States federal and state securities
laws and that the Company is relying in part upon the truth and accuracy of, and such Investor’s compliance with, the representations,
warranties, agreements, acknowledgments and understandings of such Investor set forth herein in order to determine the availability
of such exemptions and the eligibility of such Investor to acquire the Securities.

 

4.5            Disclosure
of Information. Such Investor has received or has had full access to all the information
such Investor considers necessary or appropriate to make an informed investment decision with respect to the Securities. Such Investor
further has had an opportunity to ask questions and receive answers from the Company regarding the terms and conditions of the
offering of the Securities and to obtain additional information (to the extent the Company possessed such information or could
acquire it without unreasonable effort or expense) necessary to verify any information furnished to such Investor or to which such
Investor had access. The foregoing, however, does not in any way limit or modify the representations and warranties made by the
Company in Section 3.

 

4.6            Investment
Experience. Such Investor understands that the purchase of the Securities involves
substantial risk. Such Investor (i) has experience as an investor in securities of companies in the development stage and
acknowledges that such Investor is able to fend for itself, can bear the economic risk of such Investor’s investment in the
Securities and has such knowledge and experience in financial or business matters that such Investor is capable of evaluating the
merits and risks of this investment in the Securities and protecting such Investor’s own interests in connection with this
investment in the Securities or (ii) has a preexisting personal or business relationship with the Company and certain of its
officers, directors or controlling persons of a nature and duration that enables such Investor to be aware of the character, business
acumen and financial circumstances of such persons. Such Investor has sought such accounting and legal advice as it has considered
necessary to make an informed investment decision with respect to its acquisition of its Securities. The Investor is relying solely
on their own accounting and legal advisors, and not on any statements of the Company or any of its agents or representatives, for
such accounting and legal advice with respect to its acquisition of the Securities.

 

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4.7            No
Governmental Review. Such Investor understands that no United States federal or state
agency or any other government or governmental agency has passed on or made any recommendation or endorsement of the Securities,
or the fairness or suitability of the investment in the Securities, nor have such authorities passed upon or endorsed the merits
of the offering of the Securities.

 

4.8            Organization
and Standing. Such Investor is duly organized, validly existing and in good standing
under the laws of the jurisdiction in which it was formed.

 

4.9            Accredited
Investor Status. Such Investor is an “accredited investor” within the
meaning of Regulation D promulgated under the Securities Act. “Accredited investor” includes, without limitation, (a) a
person or entity who is a director or executive officer of the Company, (b) a natural person whose individual net worth, or
joint net worth with that person’s spouse, at the time of his or her purchase exceeds $1,000,000 after subtracting the value
of such Investor’s primary residence and excluding the related amount of indebtedness secured by the primary resident up
to its fair market value, (c) a natural person who had an individual income in excess of $200,000 in each of the two most
recent years or joint income with that person's spouse in excess of $300,000 in each of those two years and has a reasonable expectation
of reaching the same income level in the current year, (d) a corporation, limited liability company or partnership having
total assets in excess of $5,000,000 that was not formed for the purpose of acquiring the Securities and (e) a trust, with
total assets in excess of $5,000,000, not formed for the specific purpose of acquiring the Securities, whose acquisition is directed
by a person who has such knowledge and experience in financial and business matters that he or she is capable of evaluated the
merits and risks of acquiring the Securities.

 

4.10            Restricted
Securities. Such Investor understands that the Securities are characterized as “restricted
securities” under the Securities Act and Rule 144 promulgated thereunder (“Rule 144”)
since they are being acquired from the Company in a transaction not involving a public offering, and that under the Securities
Act and applicable regulations thereunder the Securities may be resold without registration under the Securities Act only in certain
limited circumstances. Investor further understands that the Company is under no obligation to register the Securities and the
Company has no present plans to do so. Furthermore, such Investor is familiar with Rule 144, as presently in effect, and understands
the limitations imposed thereby and by the Securities Act on resale of the Securities without such registration. Such Investor
understands that, whether or not the Securities may be resold in the future without registration under the Securities Act, no public
market now exists for any of the Securities and that it is uncertain whether a public market will ever exist for the Securities.

 

4.11            Further
Limitations on Disposition. Without in any way limiting the representations set forth
above, such Investor further agrees not to make any disposition of all or any portion of the Securities unless and until:

 

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(a)            there
is then in effect a registration statement under the Securities Act covering such proposed disposition and such disposition is
made in accordance with such effective registration statement; or

 

(b)            such
Investor shall have notified the Company of the proposed disposition and shall have furnished the Company with a statement of the
circumstances surrounding the proposed disposition and, at the expense of such Investor or its transferee, with an opinion of counsel
reasonably satisfactory in form and substance to the Company that such disposition will not require registration of such Securities
under the Securities Act.

 

Notwithstanding the provisions of paragraphs
(a) and (b) of this Section 4.11, no such registration statement or opinion of counsel shall be required for any
transfer: (i) of any Securities in compliance with Rule 144 or Rule 144A promulgated under the Securities Act when
the Company is promptly provided evidence of such compliance; (ii) of any Securities by an Investor that is a partnership
or a corporation to (A) a partner of such partnership or stockholder of such corporation, (B) a retired partner of such
partnership who retires after the date hereof, (C) the estate of any deceased partner of such partnership or deceased stockholder
of such corporation; or (iii) by gift, will or intestate succession by any Investor to his or her spouse or lineal descendants
or ancestors or any trust for any of the foregoing; provided that in each of the foregoing cases the transferee agrees in
writing to be subject to the terms of this Agreement and the Notes to the same extent as if the transferee had been an original
Investor hereunder.

 

4.12            Legends.
Such Investor understands and agrees that the certificates evidencing the Securities will bear legends substantially similar to
those set forth below in addition to any other legend that may be required by applicable law, the Company’s Certificate of
Incorporation or Bylaws, Section 4.13 of this Agreement or any other agreement between the Company and such Investor:

 

(a)            THE
SECURITIES REPRESENTED HEREBY HAVE NOT BEEN REGISTERED UNDER THE SECURITIES ACT OF 1933, AS AMENDED (THE “ACT”),
OR UNDER THE SECURITIES LAWS OF APPLICABLE STATES. THESE SECURITIES ARE SUBJECT TO RESTRICTIONS ON TRANSFERABILITY AND RESALE AND
MAY NOT BE TRANSFERRED OR RESOLD EXCEPT AS PERMITTED UNDER THE ACT AND APPLICABLE STATE SECURITIES LAWS, PURSUANT TO REGISTRATION
UNDER SUCH LAWS OR AN EXEMPTION FROM SUCH REGISTRATION REQUIREMENTS. INVESTORS SHOULD BE AWARE THAT THEY MAY BE REQUIRED TO
BEAR THE FINANCIAL RISKS OF THIS INVESTMENT FOR AN INDEFINITE PERIOD OF TIME. THE ISSUER OF THESE SECURITIES MAY REQUIRE AN
OPINION OF COUNSEL IN FORM AND SUBSTANCE SATISFACTORY TO THE ISSUER TO THE EFFECT THAT ANY PROPOSED TRANSFER OR RESALE IS
IN COMPLIANCE WITH THE ACT AND ALL APPLICABLE STATE SECURITIES LAWS.

 

(b)            Any
legend required by the laws of the State of California, including any legend required by the California Department of Corporations,
or any other state securities laws.

 

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The legend set forth in (a) above
shall be removed by the Company from any certificate evidencing the Securities upon delivery to the Company of an opinion of counsel,
reasonably satisfactory in form and substance to the Company, that either (i) a registration statement under the Securities
Act is at that time in effect with respect to the legended security or (ii) such security can be freely transferred in a public
sale (other than pursuant to Rule 144, Rule 144A or Rule 145 promulgated under the Securities Act) without such
a registration statement being in effect and that such transfer will not jeopardize the exemption or exemptions from registration
pursuant to which the Company issued the Securities.

 

4.13            [Intentionally
Omitted.]

 

4.14            Reliance
on Business Plan. Investor understands that the oral and visual components of any
live presentation, executive summary, investment opportunity summary, product development and revenue projections, business model,
investor updates and/or similar documentation previously delivered by the Company and reviewed by Investor were incomplete and
were intended only to give Investor a general idea of the Company’s future intentions. Investor acknowledges that the Company
reserves the right to deviate from the plans set forth in such materials and that the Company is in the early stages of development
and therefore its future plans are highly speculative. Investor acknowledges that any projections contained in the materials delivered
to Investor: (a) were based on various assumptions by management that may have changed or that may prove to be incorrect and
that such assumptions are inherently subject to significant economic and competitive uncertainties and contingencies, many of which
are beyond the control of the Company and its management, and (b) were based upon assumptions with respect to future business
decisions that are subject to change. Investor acknowledges that Investor was encouraged to consult with the management of the
Company at greater length and in more depth concerning the Company’s future business plans and has done so to the extent
desired.

 

4.15            Tax
Liability. Investor has reviewed with its own tax advisors the federal, state, local
and foreign tax consequences of this investment and the transactions contemplated by this Agreement and the Notes. Investor relies
solely on such advisors and not on any statements or representations of the Company, the Company’s counsel, or any of the
Company’s agents. Investor understands that it (and not the Company) shall be responsible for its own tax liability that
may arise as a result of this investment or the transactions contemplated by this Agreement and the Notes.

 

5.            CONDITIONS
TO CLOSING.

 

5.1            Conditions
to Investors’ Obligations. The obligations of each Investor under Section 2
of this Agreement are subject to the fulfillment or waiver, on or before the Closing, of each of the following conditions, the
waiver of which shall not be effective against any Investor who does not consent to such waiver, which consent may be given by
written, oral or telephone communication to the Company or its counsel:

 

(a)            each
of the representations and warranties of the Company contained in Section 3 shall be true and correct in all material respects
on and as of the Closing with the same effect as though such representations and warranties had been made on and as of the date
of the Closing;

 

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(b)            the
Company shall have performed and complied with all agreements, obligations and conditions contained in this Agreement that are
required to be performed or complied with by it on or before the Closing and shall have obtained all approvals, consents and qualifications
necessary to complete the purchase and sale described herein;

 

(c)            the
Company shall have executed and delivered to each Investor a Note, in the form attached hereto as Exhibit A, evidencing
the Company’s indebtedness to such Investor in the amount set forth on such Investor’s signature page hereto;
and

 

(d)            the
SPAC Merger shall be consummated pursuant to the terms of the Merger Agreement substantially concurrently with the Closing.

 

5.2            Condition
to Company’s Obligations. The obligations of the Company to each Investor under
this Agreement are subject to the fulfillment or waiver on or before the Closing of each of the following conditions by such Investor:

 

(a)            Each
of the representations and warranties of such Investor contained in Section 4 shall be true and correct at the Closing with
the same effect as though such representations and warranties had been made on and as of the Closing; and

 

(b)            such
Investor shall have performed and complied with all agreements, obligations and conditions contained in this Agreement that are
required to be performed or complied with by it on or before the Closing and shall have obtained all approvals, consents and qualifications
necessary to complete the purchase and sale described herein; and

 

(c)            the
SPAC Merger shall be consummated pursuant to the terms of the Merger Agreement substantially concurrently with the Closing.

 

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6.            REGISTRATION
RIGHTS.

 

6.1            Registration
Rights. The Company agrees that, as promptly as practicable (but in any event within
ninety (90) calendar days after the consummation of the SPAC Merger), the SPAC Purchaser will file with the U.S. Securities and
Exchange Commission (the “SEC”) (at its sole cost and expense) a registration statement registering the
resale of the SPAC Shares issued to the holder of this Note (the “Registration Statement”), and it shall
use its commercially reasonable efforts to have the Registration Statement declared effective as soon as practicable after the
filing thereof. The Company agrees that the SPAC Purchaser will cause such Registration Statement or another registration statement
(which may be a “shelf” registration statement) to remain effective until the earliest of (i) two years from the
issuance of the SPAC Shares, (ii) the date on which Holder ceases to hold the SPAC Shares covered by such Registration Statement
and (iii) the first date on which Holder can sell all of its SPAC Shares under Rule 144 of the Securities Act without
limitation as to the manner of sale or the amount of such securities that may be sold. Holder agrees to disclose its beneficial
ownership, as determined in accordance with Rule 13d-3 of the Securities Exchange Act of 1934, as amended, of the SPAC Shares
to the SPAC Purchaser upon request to assist the SPAC Purchaser in making the determination described above. The SPAC Purchaser’s
obligations to include the SPAC Shares in the Registration Statement are contingent upon Holder furnishing in writing to the SPAC
Purchaser such information regarding Holder, the securities of the SPAC Purchaser held by Holder and the intended method of disposition
of the SPAC Shares as shall be reasonably requested by the SPAC Purchaser to effect the registration of the SPAC Shares, and shall
execute such documents in connection with such registration as the SPAC Purchaser may reasonably request that are customary of
a selling stockholder in similar situations. The SPAC Purchaser may delay filing or suspend the use of any such registration statement
if it determines that in order for the registration statement to not contain a material misstatement or omission, an amendment
thereto would be needed, or if such filing or use could materially affect a bona fide business or financing transaction of the
SPAC Purchaser or would require premature disclosure of information that could materially adversely affect the SPAC Purchaser (each
such circumstance, a “Suspension Event”); provided, that the SPAC Purchaser shall use commercially reasonable
efforts to make such registration statement available for the sale by Holder of such securities as soon as practicable thereafter.
Upon receipt of any written notice from the SPAC Purchaser of the happening of any Suspension Event during the period that the
Registration Statement is effective or if as a result of a Suspension Event the Registration Statement or related prospectus contains
any untrue statement of a material fact or omits to state any material fact required to be stated therein or necessary to make
the statements therein, in light of the circumstances under which they were made (in the case of the prospectus) not misleading,
Holder agrees that it will (i) immediately discontinue offers and sales of the SPAC Shares under the Registration Statement
until Holder receives (A) (x) copies of a supplemental or amended prospectus that corrects the misstatement(s) or
omission(s) referred to above and (y) notice that any post-effective amendment has become effective or (B) notice
from the SPAC Purchaser that it may resume such offers and sales, and (ii) maintain the confidentiality of any information
included in such written notice delivered by the SPAC Purchaser unless otherwise required by applicable law. If so directed by
the SPAC Purchaser, Holder will deliver to the SPAC Purchaser or destroy all copies of the prospectus covering the SPAC Shares
in Holder’s possession; provided, however, that this obligation to deliver or destroy all copies of the prospectus covering
the SPAC Shares shall not apply to (i) the extent that Holder is required to retain a copy of such prospectus (A) in
order to comply with applicable legal, regulatory, self-regulatory or professional requirements or (B) in accordance with
a bona fide pre-existing document retention policy or (ii) copies stored electronically on archival servers as a result of
automatic data back-up.

 

7.            GENERAL
PROVISIONS.

 

7.1            Survival
of Warranties. The representations, warranties and covenants of the Company and the
Investors contained in or made pursuant to this Agreement shall survive the execution and delivery of this Agreement, the Closing,
and shall in no way be affected by any investigation of the subject matter thereof made by or on behalf of any of the Investors
or the Company, as the case may be.

 

7.2            Successors
and Assigns. The terms and conditions of this Agreement shall inure to the benefit
of and be binding upon the respective successors and assigns of the parties, provided, however, that nothing in this
Section 7.2 shall permit any of the Investors to transfer or assign any of the Securities acquired under this Agreement except
as provided in Section 4 and in the Notes.

 

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7.3            Governing
Law. This Agreement shall be governed by and construed under the internal laws of
the State of California as applied to agreements among California residents entered into and to be performed entirely within California,
without reference to principles of conflict of laws or choice of laws.

 

7.4            Counterparts;
Facsimile Signatures. This Agreement may be executed in two or more counterparts,
each of which shall be deemed an original, but all of which together shall constitute one and the same instrument. This Agreement
may be executed and delivered by facsimile, or by email in portable document format (.pdf) and delivery of the signature page by
such method will be deemed to have the same effect as if the original signature had been delivered to the other parties hereto.

 

7.5            Headings;
Interpretation. In this Agreement, (i) the meaning of defined terms shall be
equally applicable to both the singular and plural forms of the terms defined; (ii) the captions and headings are used only
for convenience and are not to be considered in construing or interpreting this Agreement and (iii) the words “including,”
 “includes” and “include” shall be deemed to be followed by the words “without limitation”.
All references in this Agreement to sections, paragraphs, exhibits and schedules shall, unless otherwise provided, refer to sections
and paragraphs hereof and exhibits and schedules attached hereto, all of which exhibits and schedules are incorporated herein by
this reference.

 

7.6            Notices.
Unless otherwise provided herein, any notice required or permitted under this Agreement shall be given in writing and shall be
deemed effectively given (i) at the time of personal delivery, if delivered in person; (ii) when sent, if sent by electronic
mail or by facsimile during the recipient’s normal business hours, and if not sent during normal business hours, then on
the next business day; (iii) one (1) business day after deposit with an express overnight courier for United States deliveries,
or three (3) business days after deposit with an express courier for deliveries outside of the United States, in each case
with proof of delivery from the courier requested; or (iv) four (4) business days after deposit in the United States
mail by certified mail (return receipt requested) for United States deliveries when addressed to an Investor at the address set
forth on such Investor’s signature page hereto or, in the case of the Company, at 19925 Stevens Creek Blvd., Suite 100,
Cupertino, California, 95014, or at such other address as any party or the Company may designate for itself to receive notices
by giving ten (10) days’ advance written notice to all required parties in accordance with the provisions of this Section,
with copies to (which shall not constitute notice) Lowenstein Sandler LLP, One Lowenstein Drive, Roseland, New Jersey 07068, Attention:
Steven M. Skolnick, Esq.

 

7.7            No
Finder’s Fees. Each party represents that it neither is nor will be obligated
for any finder’s or broker’s fee or commission in connection with the transactions contemplated by this Agreement.
Each Investor agrees to indemnify and to hold harmless the Company from any liability for any commission or compensation in the
nature of a finder’s or broker’s fee (and any asserted liability) for which the Investor or any of its directors, officers,
partners, members, employees or representatives is responsible. The Company agrees to indemnify and hold harmless each Investor
from any liability for any commission or compensation in the nature of a finder’s or broker’s fee (and any asserted
liability) for which the Company or any of its officers, employees or representatives is responsible.

 

    11

     

    

 

7.8            Amendments
and Waivers. Any term of this Agreement and the Notes may be amended and the observance
of any term of this Agreement and the Notes may be waived (either generally or in a particular instance and either retroactively
or prospectively), only with the written consent of the Company and the holders of Notes representing at least a majority of the
aggregate Principal Balances (as defined in the Notes) of all the Notes then outstanding (the “Majority Holders”). 
Any amendment or waiver effected in accordance with this Section 7.8 shall be binding upon each holder of Notes then outstanding,
each future holder of such securities, and the Company; provided, however, that without such Investor’s written
consent, no amendment or waiver of any term of this Agreement shall be effective against an Investor that materially and adversely
affects such Investor’s rights hereunder in a manner that is materially different from and disproportionate to the effect
on other Investors. Notwithstanding anything to the contrary contained herein or in the Notes, from the date of this Agreement
until the earlier of (i) the consummation of the transactions contemplated by the SPAC Merger Agreement or (ii) the termination
of the SPAC Merger Agreement in accordance with its terms, neither this Agreement, nor any of the Notes, may be amended, supplemented
or modified, nor may any provision of this Agreement or the Notes be waived, in each case without the prior written consent of
SPAC Purchaser (such consent not to be unreasonably withheld, delayed or conditioned). SPAC Purchaser is an express intended third
party beneficiary of this Section 7.8 and shall have the right to enforce the terms hereof as if it were a direct party hereto.

 

7.9            Severability.
If any provision of this Agreement is determined by any court or arbitrator of competent jurisdiction to be invalid, illegal or
unenforceable in any respect, such provision will be enforced to the maximum extent possible given the intent of the parties hereto.
If such clause or provision cannot be so enforced, such provision shall be stricken from this Agreement and the remainder of this
Agreement shall be enforced as if such invalid, illegal or unenforceable clause or provision had (to the extent not enforceable)
never been contained in this Agreement. Notwithstanding the foregoing, if the value of this Agreement based upon the substantial
benefit of the bargain for any party is materially impaired, which determination as made by the presiding court or arbitrator of
competent jurisdiction shall be binding, then both parties agree to substitute such provision(s) through good faith negotiations.

 

7.10            Entire
Agreement. This Agreement, together with all exhibits and schedules hereto and the
other Financing Documents, constitute the entire agreement and understanding of the parties with respect to the subject matter
hereof and supersede any and all prior negotiations, correspondence, agreements, understandings, duties or obligations between
the parties with respect to the subject matter hereof.

 

7.11            Further
Assurances. From and after the date of this Agreement, upon the request of any Investor
or the Company, the Company and the Investors shall execute and deliver such instruments, documents or other writings as may be
reasonably necessary or desirable to confirm and carry out and to effectuate fully the intent and purposes of this Agreement.

 

[Signature
Pages Follow]

 

    12

     

    

 

IN WITNESS WHEREOF,
the undersigned has executed this Note Purchase Agreement effective as of the date first written above.

 

	REVIVA PHARMACEUTICALS, INC.:
	 
	Signature:	 	 	 
	 	 	 	 
	Name:	Laxminarayan Bhat, Ph.D.	 	 
	 	 	 	 
	Title:	President and Chief Executive Officer	 
	 	 	 
	Phone:	(408) 960.2209	 	 
	 	 	 	 
	Fax:	(408) 904.6270	 	 
	 	 	 	 
	E-mail:	LBhat@Revivapharma.com	 	 

 

Attachments:

 

	Exhibit A	–	Form of Note
	Exhibit B	–	Schedule of Exceptions

 

[Signature
Page to Reviva Note Purchase Agreement (2020 Judgement Notes)]

 

    

     

    

 

IN WITNESS WHEREOF,
the undersigned has executed this Note Purchase Agreement effective as of the date first written above.

 

	 	 	INVESTOR: 
	 	 	 
	 	Signature:	 
	 	 	 
	 	Print Name:	 
	 	 	 
	 	Signature	 
	 	 	 
	 	Print Name	 
	 	 	 
	 	Title (if applicable):	 
	 	 	 
	 	Dollar Amount Invested (Notes):	 
	 	 	 
	 	Address:	 
	 	 	 
	 	Phone No:	 
	 	 	 
	 	Fax No.:	 
	 	 	 
	 	E-mail:	 
	 	 	 
	 	Date of Investment: 	 
	 	 	 	 

Attachments:

 

	Exhibit A	–	Form of Note
	Exhibit B	–	Schedule of Exceptions

 

[Signature
Page to Reviva Note Purchase Agreement (2020 Judgement and Working Cap Notes)]

 

    

     

    

 

IN WITNESS WHEREOF,
the undersigned has executed this Note Purchase Agreement effective as of the date first written above.

 

	 	 	INVESTOR: 
	 	 	 
	 	Signature:	 
	 	 	 
	 	Print Name:	 
	 	 	 
	 	Signature	 
	 	 	 
	 	Print Name	 
	 	 	 
	 	Title (if applicable):	 
	 	 	 
	 	Dollar Amount Invested (Notes):	 
	 	 	 
	 	Address:	 
	 	 	 
	 	Phone No:	 
	 	 	 
	 	Fax No.:	 
	 	 	 
	 	E-mail:	 
	 	 	 
	 	Date of Investment: 	 
	 	 	 	 

Attachments:

 

	Exhibit A	–	Form of Note
	Exhibit B	–	Schedule of Exceptions

 

[Signature
Page to Reviva Note Purchase Agreement (2020 Judgement and Working Cap Notes)]

 

    

     

    

 

EXHIBIT A

 

FORM OF
NOTE

 

    

     

    

 

EXHIBIT B

 

SCHEDULE OF EXCEPTIONSExhibit 10.21

 

REVIVA PHARMACEUTICALS HOLDINGS, INC.

(f/k/a Tenzing Acquisition Corp.)

250 West 55th Street, Suite 13D

New York, New York 10019

 

December 14, 2020

 

MAXIM GROUP LLC

405 Lexington Avenue

New York, NY 10174

Attention: Head of Investment Banking

 

Re: Payment of Deferred Underwriting
Commission

 

Ladies and Gentlemen:

 

Reference is hereby
made to that certain underwriting agreement, dated as of August 20, 2018 (the “Underwriting Agreement”),
by and between Tenzing Acquisition Corp., a company incorporated in the British Virgin Islands (which has since been converted
into Reviva Pharmaceuticals Holdings, Inc., a Delaware corporation through a statutory re-domestication (the “Conversion”))
(together with any successor thereto, the “Company”), and Maxim Group LLC (“Maxim Group”),
pursuant to which Maxim Group acted as the representative of several underwriters in connection with the Company’s initial
public offering of units. Capitalized terms used but not defined in this letter agreement (this “Letter”)
shall have the meanings given to such terms in the Underwriting Agreement.

 

1.             Pursuant
to Section 1.3 of the Underwriting Agreement, 3.5% of the gross proceeds from the sale of the Firm Units ($1,925,000) and
3.5% of the gross proceeds from the sale of the Option Units ($288,750), for an aggregate of $2,213,750 (the “Deferred
Underwriting Commission”), were deposited in and held in the Trust Account and will be payable directly from the
Trust Account, without accrued interest, to Maxim Group for its own account upon consummation of the Business Combination. Each
of the Company and Maxim Group hereby agree that with respect to the Company’s proposed Business Combination with Reviva
Pharmaceuticals, Inc., a Delaware corporation (the “Reviva Business Combination”), in lieu of the
payment of $2,113,750 of the Deferred Underwriting Commission in cash, the Company shall, at the closing of the Reviva Business
Combination (the ”Closing”), issue to Maxim Group’s affiliate, Maxim Partners, LLC (“Maxim
Partners” and together with Maxim Group, “Maxim”), an aggregate of 300,000 shares of common
stock (the “Shares”), par value $0.0001 per share, of the Company after giving effect to the Conversion,
with the remaining $100,000 of the Deferred Underwriting Commission being paid in cash upon the Closing.

 

     

     

    

 

2.             The
Company agrees that, within ninety (90) days after the Closing, it will file with the Securities and Exchange Commission (at its
sole cost and expense) a registration statement registering the resale of the Shares (the “Registration Statement”),
and it shall use its commercially reasonable efforts to have the Registration Statement declared effective as soon as practicable
after the filing thereof. The Company acknowledges and agrees that it will include the Shares for resale registration in the registration
statement (the “Non-Redemption Registration Statement”) to be filed by the Company after the Closing
under the Registration Rights Agreement to be entered into by the Company at the Closing pursuant to the Non-Redemption Agreement,
dated as of December 8, 2020 (the “Non-Redemption Agreement”), by and among the Company, Sponsor
and the Company’s shareholder named therein (the “Shareholder”) for the resale of the shares of
the Company issued to the Shareholder under the Non-Redemption Agreement and the Company warrants (and underlying shares of Common
Stock upon exercise of such warrants) transferred from the Sponsor to the Shareholder thereunder (together with such shares, the
 “Shareholder Securities”); provided, that Maxim acknowledges that the Shareholder Securities will take
priority over the Shares with respect to any registration, and if all of the securities to be registered under the Non-Redemption
Registration Statement cannot for any reason be registered thereunder, the Shares will not be included in the final Non-Redemption
Registration Statement unless all of the Shareholder Securities are included and registered thereunder, and in such case, the Company
will file another resale registration statement for the resale of the Shares as promptly thereafter as practicable. The Company
agrees that it will cause such Registration Statement or another registration statement (which may be a “shelf” registration
statement) to remain effective until the earliest of (i) two years from the issuance of the Shares, (ii) the date on
which Maxim ceases to hold the Shares covered by such Registration Statement and (iii) the first date on which Maxim can sell
all of its Shares under Rule 144 of the Act, without limitation as to the manner of sale or the amount of such securities
that may be sold. Maxim agrees to disclose its beneficial ownership, as determined in accordance with Rule 13d-3 of the Exchange
Act, of the Shares to the Company upon request to assist the Company in making the determination described above. The Company’s
obligations to include the Shares in the Registration Statement are contingent upon Maxim furnishing in writing to the Company
such information regarding Maxim, the securities of the Company held by Maxim and the intended method of disposition of the Shares
as shall be reasonably requested by the Company to effect the registration of the Shares, and shall execute such documents in connection
with such registration as the Company may reasonably request that are customary of a selling stockholder in similar situations.
The Company may delay filing or suspend the use of any such registration statement if it determines that in order for the registration
statement to not contain a material misstatement or omission, an amendment thereto would be needed, or if such filing or use could
materially affect a bona fide business or financing transaction of the Company or would require premature disclosure of information
that could materially adversely affect the Company (each such circumstance, a “Suspension Event”); provided,
that the Company shall use commercially reasonable efforts to make such registration statement available for the sale by Maxim
of such securities as soon as practicable thereafter. Upon receipt of any written notice from the Company of the happening of any
Suspension Event during the period that the Registration Statement is effective or if as a result of a Suspension Event the Registration
Statement or related prospectus contains any untrue statement of a material fact or omits to state any material fact required to
be stated therein or necessary to make the statements therein, in light of the circumstances under which they were made (in the
case of the prospectus) not misleading, Maxim agrees that it will (i) immediately discontinue offers and sales of the Shares
under the Registration Statement until Maxim receives (A) (x) copies of a supplemental or amended prospectus that corrects
the misstatement(s) or omission(s) referred to above and (y) notice that any post-effective amendment has become
effective or (B) notice from the Company that it may resume such offers and sales, and (ii) maintain the confidentiality
of any information included in such written notice delivered by the Company unless otherwise required by applicable law. If so
directed by the Company, Maxim will deliver to the Company or destroy all copies of the prospectus covering the Shares in Maxim’s
possession; provided, however, that this obligation to deliver or destroy all copies of the prospectus covering the Shares shall
not apply to (i) the extent that Maxim is required to retain a copy of such prospectus (A) in order to comply with applicable
legal, regulatory, self-regulatory or professional requirements or (B) in accordance with a bona fide pre-existing document
retention policy or (ii) copies stored electronically on archival servers as a result of automatic data back-up.

 

3.             Maxim
hereby represents, warrants and covenants to the Company as follows:

 

(a)           Maxim
will be acquiring the Shares for its own account, not as a nominee or agent. Maxim will not sell, assign or transfer any Shares
at any time in violation of the Act, or applicable state securities laws. Maxim acknowledges that the Shares cannot be sold unless
subsequently registered under the Act and applicable state securities laws or an exemption from such registration is available.
Maxim understands that the Shares (i) have not been (and upon their sale will not be) registered under the Act or any state
securities laws, (ii) have been offered and will be sold in reliance upon an exemption from the registration and prospectus
delivery requirements of the Act, and (iii) will be issued in reliance upon exemptions from the registration and prospectus
delivery requirements of state securities laws which relate to private offerings. Pursuant to the foregoing, Maxim acknowledges
that until such time as the resale of the Shares have been registered under the Act or may otherwise may be sold pursuant to an
exemption from registration, any certificates representing any Shares acquired by Maxim shall bear a customary restrictive legend
(and a stop-transfer order may be placed against transfer of any certificates evidencing such Shares) reflecting such limitations
in form and substance reasonably acceptable to the Company.

 

    2 

     

    

 

(b)           Maxim
has knowledge, skill and experience in financial, business and investment matters relating to an investment of this type and is
capable of evaluating the merits and risks of such investment and protecting its interest in connection with the acquisition of
the Shares. Maxim understands that the acquisition of the Shares is a speculative investment and involves substantial risks and
that Maxim could lose its entire investment. Further, Maxim has (i) carefully read and considered the risks identified in
the Disclosure Documents (as defined below) and (ii) carefully considered and understands all of the risks related to the
Company, the Shares and this Letter. Acknowledging the very significant tax impact analysis and other analyses that is warranted
in determining the consequences to it of purchasing and owning the Shares, to the extent deemed necessary by Maxim, Maxim has had
the opportunity to retain, at its own expense, and relied upon, appropriate professional advice regarding the investment, tax and
legal merits and consequences of the foregoing, including without limitation purchasing and owning the Shares. Maxim has the ability
to bear the economic risks of its investment in the Company, including without limitation a complete loss of the investment, and
Maxim has no need for liquidity in such investment.

 

(c)           Maxim
has been furnished by or on behalf of the Company all information (or provided access to all information it reasonably requested)
regarding the business and financial condition of the Company, the expected plans for future business activities, and the merits
and risks of an investment in the Shares which Maxim has reasonably requested or otherwise needs to evaluate the investment in
the Shares. Maxim is in receipt of and has carefully read and understands the following items (collectively, the “Disclosure
Documents”): (i) the final prospectus of the Company, dated as of August 20, 2018, and filed with the Commission
on August 22, 2018 (File Nos. 333-226263 and 333-226952) (the “IPO Prospectus”); (ii) the final
prospectus/proxy statement, dated as of November 10, 2020, relating to the Reviva Business Combination, filed by the Company
with the Commission on November 12, 2020 and (iii) each other filing made by the Company with the Commission following
the filing of the IPO Prospectus through the date of this Letter. Maxim acknowledges that neither the Company, nor any of its agents
or representatives has made or makes any representation or warranty to Maxim in respect of the Company, the Shares, the Reviva
Business Combination or this Letter, other than the representations and warranties contained in this Letter. In making its investment
decision to acquire the Shares, Maxim is relying solely on investigations made by Maxim and its agents and representatives.

 

(d)           Maxim
acknowledges that it has been advised that: (i) the Shares have not been approved or disapproved by the Commission or any
state securities commission nor has the Commission or any state securities commission passed upon the accuracy or adequacy of any
representations by the Company, and any representation to the contrary is a criminal offense; (ii) in making an investment
decision, Maxim must rely on its own examination of the Company and the Shares, including without limitation the merits and risks
involved, the Shares have not been recommended by any federal or state securities commission or regulatory authority, and the foregoing
authorities have not confirmed the accuracy or determined the adequacy of any representation (and any representation to the contrary
is a criminal offense); (iii) any Shares will be “restricted securities” within the meaning of Rule 144 under
the Act, are subject to restrictions on transferability and resale and may not be transferred or resold except as permitted under
the Act and applicable state securities laws, pursuant to registration or exemption therefrom. Maxim is aware of the provisions
of Rule 144 are not currently available and, in the future, may not become available for resale of any of the Shares and that
the Company is an issuer subject to Rule 144(i) under the Act.

 

    3 

     

    

 

(e)           Maxim
further represents and warrants that it is a “qualified institutional buyer” within the meaning of Rule 144A under
the Act. As of the date of this Letter, Maxim and its Affiliates do not have, and during the thirty (30) day period prior to the
date of this Letter, Maxim and its Affiliates have not, in a seller, transferor or other similar capacity, entered into, any “put
equivalent position” as such term is defined in Rule 16a-1 of the Exchange Act or short sale positions with respect
to the securities of the Company. In addition, Maxim shall comply with all applicable provisions of Regulation M promulgated under
the Act. For purpose of this Letter, “Affiliate” means affiliate as such term is defined in Rule 12b-2 under the
Exchange Act.

 

(f)            Maxim
has the full legal right and power and all authority and approval required (i) to execute and deliver, or authorize execution
and delivery of, this Letter and all other instruments executed and delivered by or on behalf of Maxim in connection with the acquisition
of the Shares, (ii) to delegate authority pursuant to power of attorney and (iii) to acquire and hold the Shares. The
signature of the person signing on behalf of Maxim is binding upon Maxim. This Letter has been duly authorized, executed and delivered
by Maxim and constitutes a legal, valid and binding obligation of Maxim enforceable against Maxim in accordance with its terms,
except as such enforceability may be limited by: (i) applicable bankruptcy, insolvency, reorganization, moratorium or other
similar laws in effect that limit creditors’ rights generally; (ii) equitable limitations on the availability of specific
remedies; (iii) principles of equity (regardless of whether such enforcement is considered in a proceeding in law or in equity);
and (iv) to the extent rights to indemnification and contribution may be limited by federal securities laws or the public
policy underlying such laws.

 

(g)           Maxim
understands and confirms that the Company will rely on the representations and covenants contained herein in effecting the transactions
contemplated by this Letter. Maxim agrees to notify the Company immediately upon the occurrence of any event that would cause any
representation, warranty, covenant or other statement contained in this Letter to be false or incorrect or of any change in any
statement made herein.

 

(h)           Neither
Maxim nor, to the extent it has them, any of its shareholders, members, managers, general or limited partners, directors, Affiliates
or executive officers (collectively with Maxim, the “Covered Persons”), are subject to any of the “Bad
Actor” disqualifications described in Rule 506(d) under the Act (a “Disqualification Event”),
except for a Disqualification Event covered by Rule 506(d)(2) or (d)(3). Maxim has exercised reasonable care to determine
whether any Covered Person is subject to a Disqualification Event. The acquisition of Shares by Maxim will not subject the Company
to any Disqualification Event.

 

(i)            Neither
Maxim nor any of its directors, managers, officers or owners are the subject of any U.S. Sanctions Laws, including but not limited
to any laws, regulations, executive orders, or other restrictions or prohibitions administered by the U.S. Department of the Treasury’s
Office of Foreign Assets Control (“OFAC”). Neither Maxim nor any of its directors, managers, officers
or owners are: (i) designated on any list of restricted parties maintained by the U.S. Government including, but not limited
to, OFAC’s Specially Designated Nationals and Blocked Persons List, the list of Foreign Sanctions Evaders, or the Sectoral
Sanctions Identifications List; the U.S. Department of Commerce’s Denied Persons List or Entity List; or the U.S. Department
of State’s Debarred List; or (ii) located, organized, resident, or doing business in any country or territory that is,
or whose government is, the subject of comprehensive territorial U.S. Sanctions Laws, including, without limitation Crimea, Cuba, Iran,
North Korea, and Syria. To the extent required, Maxim maintains policies and procedures reasonably designed for the screening of
its investors against U.S. Government restricted party lists, including without limitation the lists herein referenced.

 

    4 

     

    

 

4.            The
Company hereby represents, warrants and covenants to Maxim as follows:

 

(a)           The
Company has been duly formed or incorporated and is validly existing in good standing under the laws of its jurisdiction of incorporation
or formation. The Company has the full legal right and power and all authority and approval required (i) to execute and deliver,
or authorize execution and delivery of, this Letter and all other instruments executed and delivered by or on behalf of the Company
in connection with the issuance of the Shares, and (ii) to perform its obligations under this Letter. The signature of the
person signing on behalf of the Company is binding upon the Company. This Letter has been duly authorized, executed and delivered
by the Company and constitutes a legal, valid and binding obligation of the Company enforceable against the Company in accordance
with its terms, except as such enforceability may be limited by: (i) applicable bankruptcy, insolvency, reorganization, moratorium
or other similar laws in effect that limit creditors’ rights generally; (ii) equitable limitations on the availability
of specific remedies; (iii) principles of equity (regardless of whether such enforcement is considered in a proceeding in
law or in equity); and (iv) to the extent rights to indemnification and contribution may be limited by federal securities
laws or the public policy underlying such laws.

 

(b)           The
Shares have been duly authorized and, when issued and delivered to Maxim Partners in accordance with the terms of this Letter,
the Shares will be validly issued, fully paid and non-assessable and will not have been issued in violation of or subject to any
preemptive or similar rights created under the Company’s organizational documents or under the laws of the State of Delaware.

 

(c)           Assuming
the accuracy of Maxim’s representations and warranties set forth in Section 3, in connection with the offer, sale and
delivery of the Shares in the manner contemplated by this Letter, it is not necessary to register the issuance of the Shares under
the Act.

 

(d)           The
issuance of the Shares and the compliance by the Company with all of the provisions of this Letter and the consummation of the
transactions herein will be done in accordance with the NASDAQ marketplace rules and will not conflict with or result in a
material breach or material violation of any of the terms or provisions of, or constitute a material default under, or result in
the creation or imposition of any lien, charge or encumbrance upon any of the property or assets of the Company or any of its subsidiaries
pursuant to the terms of (i) any indenture, mortgage, deed of trust, loan agreement, license, lease or any other agreement
or instrument to which the Company or any of its subsidiaries is a party or by which the Company or any of its subsidiaries is
bound or to which any of the property or assets of the Company is subject, which would have a material adverse effect on the business,
properties, financial condition, stockholders' equity or results of operations of the Company and its subsidiaries, taken as a
whole (a “Material Adverse Effect”), or materially affect the validity of the Shares or the legal authority
of the Company to comply in all material respects with the terms of this Letter; (ii) result in any material violation of
the provisions of the organizational documents of the Company; or (iii) result in any violation of any statute or any judgment,
order, rule or regulation of any court or governmental agency or body, domestic or foreign, having jurisdiction over the Company
or any of its properties that would have a Material Adverse Effect or materially affect the validity of the Shares or the legal
authority of the Company to comply with this Letter; subject, in the case of the foregoing clauses (i) and (iii) with
respect to the consummation of the transactions therein contemplated.

 

    5 

     

    

 

5.             The
terms of this Letter shall be interpreted, enforced, governed by and construed in a manner consistent with the provisions of the
Underwriting Agreement. Except as expressly provided in this Letter, all of the terms and provisions in the Underwriting Agreement
are and shall remain in full force and effect, on the terms and subject to the conditions set forth therein. This Letter does not
constitute, directly or by implication, an amendment, modification or waiver of any provision of the Underwriting Agreement, or
any other right, remedy, power or privilege of any party to the Underwriting Agreement, except as expressly set forth herein. Any
reference to the Underwriting Agreement or any other agreement, document, instrument or certificate entered into or issued in connection
therewith shall hereinafter mean the Underwriting Agreement, as amended or modified by this Letter (or as the Underwriting Agreement
may be further amended or modified after the date hereof in accordance with the terms thereof).

 

[Remainder of page intentionally
left blank; Signature page follows.]

 

    6 

     

    

 

Please acknowledge
your agreement and acceptance to the foregoing by signing below and returning it to the undersigned at your earliest convenience.

 

	 	Very truly yours,
	 	 
	 	REVIVA PHARMACEUTICALS HOLDINGS, INC.
	 	 
	 	By:	 /s/ Rahul Nayar                  

	 	Name: Rahul Nayar
	 	Title: Chief Executive Officer

 

Accepted and agreed to as of the date first set forth
above:

 

MAXIM GROUP LLC

 

	By:	/s/ Cliff
Teller	 
	Name: Cliff Teller	 
	Title: Head of Banking	 
	 	 
	MAXIM PARTNERS LLC	 
	 	 
	By:	/s/ Cliff Teller	 
	Name: Cliff Teller	 
	Title: Head of Banking	 

 

{Signature Page to Maxim Side Letter}

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