Exhibit 4.1


 


WARRANT AGREEMENT


 


This Warrant Agreement
is made as of October 7, 2020 between Petra Acquisition, Inc., a Delaware corporation, with offices at 5 West 21st
Street, New York, NY 10010 (“Company”), and Continental Stock Transfer & Trust Company, a New York corporation,
with offices at 1 State Street, New York, New York 10004 (“Warrant Agent”).


 


WHEREAS, the Company
is engaged in a public offering (“Public Offering”) of up to 70,000,000 units, each unit (“Unit”)
comprised of one share of common stock of the Company, par value $.001 per share (“Common Stock”), and one warrant,
where each warrant entitles the holder to purchase one share of Common Stock at a price of $11.50 per share, subject to adjustment
as described herein, and, in connection therewith, will issue and deliver up to 8,050,000 warrants (the “Public Warrants”)
to the public investors in connection with the Public Offering; and


 


WHEREAS, the Company
has filed with the Securities and Exchange Commission (the “SEC”) a Registration Statement on Form S-1, No.
333-240175 (“Registration Statement”), for the registration, under the Securities Act of 1933, as amended (“Act”)
of, among other securities, the Public Warrants; and


 


WHEREAS, the Company
has received binding commitments (“Subscription Agreements”) from Petra Investment Holdings, LLC to purchase
up to an aggregate of 3,150,000 Warrants (the “Private Warrants”), including those underlying Units, upon consummation
of the Public Offering; and


 


WHEREAS, the Company
may issue up to an additional 1,500,000 Warrants (“Working Capital Warrants”), including those underlying Units,
in satisfaction of certain working capital loans made by the Company’s officers, directors, initial stockholders, and affiliates;
and


 


WHEREAS, following
consummation of the Public Offering, the Company may issue additional warrants (“Post IPO Warrants” and together
with the Public Warrants, Private Warrants, and Working Capital Warrants, the “Warrants”) in connection with,
or following the consummation by the Company of, a Business Combination (defined below); and


 


WHEREAS, the Company
desires the Warrant Agent to act on behalf of the Company, and the Warrant Agent is willing to so act, in connection with the issuance,
registration, transfer, exchange, redemption, and exercise of the Warrants; and


 


WHEREAS, the Company
desires to provide for the form and provisions of the Warrants, the terms upon which they shall be issued and exercised, and the
respective rights, limitation of rights, and immunities of the Company, the Warrant Agent, and the holders of the Warrants; and


 


WHEREAS, all acts and
things have been done and performed which are necessary to make the Warrants, when executed on behalf of the Company and countersigned
by or on behalf of the Warrant Agent, as provided herein, the valid, binding, and legal obligations of the Company, and to authorize
the execution and delivery of this Agreement.


 


NOW, THEREFORE, in
consideration of the mutual agreements herein contained, the parties hereto agree as follows:


 


1. Appointment of Warrant Agent.
The Company hereby appoints the Warrant Agent to act as agent for the Company for the Warrants, and the Warrant Agent hereby accepts
such appointment and agrees to perform the same in accordance with the terms and conditions set forth in this Agreement.


 






    


     


    

 


2. Warrants.


 


2.1. Form
of Warrant. Each Warrant shall be issued in registered form only, shall be in substantially the form of Exhibit A
hereto, the provisions of which are incorporated herein and shall be signed by, or bear the facsimile signature of, the
Chairman of the Board of Directors or Chief Executive Officer and Treasurer, Secretary or Assistant Secretary of the Company
and shall bear a facsimile of the Company’s seal. In the event the person whose facsimile signature has been placed
upon any Warrant shall have ceased to serve in the capacity in which such person signed the Warrant before such Warrant is
issued, it may be issued with the same effect as if he or she had not ceased to be such at the date of issuance.


 


2.2. Uncertificated
Warrants. Notwithstanding anything herein to the contrary, any Warrant, or portion thereof, may be issued as part of, and be
represented by, a Unit, and any Warrant may be issued in uncertificated or book-entry form through the Warrant Agent and/or the
facilities of The Depository Trust Company (the “Depositary”) or other book-entry depositary system, in each
case as determined by the Board of Directors of the Company or by an authorized committee thereof. Any Warrant so issued shall
have the same terms, force and effect as a certificated Warrant that has been duly countersigned by the Warrant Agent in accordance
with the terms of this Agreement.


 


2.3. Effect
of Countersignature. Except with respect to uncertificated Warrants as described above, unless and until countersigned by the
Warrant Agent pursuant to this Agreement, a Warrant shall be invalid and of no effect and may not be exercised by the holder thereof.


 


2.4. Registration.


 


2.4.1. Warrant
Register. The Warrant Agent shall maintain books (“Warrant Register”) for the registration of original issuance
and the registration of transfer of the Warrants. Upon the initial issuance of the Warrants, the Warrant Agent shall issue and
register the Warrants in the names of the respective holders thereof in such denominations and otherwise in accordance with instructions
delivered to the Warrant Agent by the Company.


 


2.4.2. Registered
Holder. Prior to due presentment for registration of transfer of any Warrant, the Company and the Warrant Agent may deem and
treat the person in whose name such Warrant is then registered in the Warrant Register (“registered holder”)
as the absolute owner of such Warrant and of each Warrant represented thereby (notwithstanding any notation of ownership or other
writing on the Warrant certificate made by anyone other than the Company or the Warrant Agent), for the purpose of any exercise
thereof, and for all other purposes, and neither the Company nor the Warrant Agent shall be affected by any notice to the contrary.


 


2.5. Detachability
of Warrants. The securities comprising the Units will not be separately transferable until the 90th day following
the date of the prospectus or, if such 90th day is not on a day, other than Saturday, Sunday or federal holiday,
on which banks in New York City are generally open for normal business (a “Business Day”), then on the immediately
succeeding Business Day following such date, or earlier with the consent of LifeSci Capital LLC and Ladenburg Thalmann & Co.
Inc. (the “Representatives”), as representatives of the several underwriters, but in no event will the Representatives
allow separate trading of the securities comprising the Units until (i) the Company has filed a Current Report on Form 8-K which
includes an audited balance sheet reflecting the receipt by the Company of the gross proceeds of the Public Offering including
the proceeds received by the Company from the exercise of the underwriters’ over-allotment option in the Public Offering,
if the over-allotment option is exercised prior to the filing of the Form 8-K, and (ii) the Company has issued a press release
and has filed a Current Report on Form 8-K announcing when such separate trading shall begin (the “Detachment Date”).


 


2.6. Private
Warrant and Working Capital Warrant Attributes. The Private Warrants and Working Capital Warrants will be issued in the same
form as the Public Warrants but they (i) will not be redeemable by the Company and (ii) may be exercised for cash or on a cashless
basis at the holder’s option, in either case as long as they are held by the initial purchasers or their permitted transferees
(as prescribed in Section 5.6 hereof). Once a Private Warrant or Working Capital Warrant is transferred to a holder other than
an affiliate or permitted transferee, it shall be treated as a Public Warrant hereunder for all purposes.


 


2.7. Post IPO
Warrants. The Post IPO Warrants, when and if issued, shall have the same terms and be in the same form as the Public Warrants
except as may be agreed upon by the Company.


 






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3. Terms and Exercise of Warrants


 


3.1. Warrant
Price. Each Warrant shall, when countersigned by the Warrant Agent (except with respect to uncertificated Warrants), entitle
the registered holder thereof, subject to the provisions of such Warrant and of this Agreement, to purchase from the Company the
number of shares of Common Stock stated therein, at the price of $11.50 per share, subject to the adjustments provided in Section
4 hereof and in the last sentence of this Section 3.1. The term “Warrant Price” as used in this Agreement refers to
the price per share at which the shares of Common Stock may be purchased at the time a Warrant is exercised. The Company in its
sole discretion may lower the Warrant Price at any time prior to the Expiration Date (as defined below) for a period of not less
than twenty (20) Business Days; provided, that the Company shall provide at least twenty (20) days’ prior written notice
of such reduction to registered holders of the Warrants and, provided further that any such reduction shall be applied consistently
to all of the Warrants.


 


3.2. Duration
of Warrants. A Warrant may be exercised only during the period commencing on the later of 30 days after the consummation by
the Company of a merger, share exchange, asset acquisition, stock purchase, recapitalization, reorganization or other similar business
combination with one or more businesses or entities (“Business Combination”) (as described more fully in the
Registration Statement) or 12 months from the closing of the Public Offering, and terminating at 5:00 p.m., New York City time
on the earlier to occur of (i) five years from the consummation of a Business Combination, (ii) the Redemption Date as provided
in Section 6.2 of this Agreement and (iii) the liquidation of the Company (“Expiration Date”). The period of
time from the date the Warrants will first become exercisable until the expiration of the Warrants shall hereafter be referred
to as the “Exercise Period.” Except with respect to the right to receive the Redemption Price (as set forth in Section
6 hereunder), as applicable, each Warrant not exercised on or before the Expiration Date shall become void, and all rights thereunder
and all rights in respect thereof under this Agreement shall cease at the close of business on the Expiration Date. The Company
in its sole discretion may extend the duration of the Warrants by delaying the Expiration Date; provided, however, that the Company
will provide at least twenty (20) days’ prior written notice of any such extension to registered holders and, provided further
that any such extension shall be applied consistently to all of the Warrants.


 


3.3. Exercise
of Warrants.


 


3.3.1. Payment.
Subject to the provisions of the Warrant and this Agreement, a Warrant, when countersigned by the Warrant Agent, may be exercised
by the registered holder thereof by surrendering it, at the office of the Warrant Agent, or at the office of its successor as Warrant
Agent, in the Borough of Manhattan, City and State of New York, with the subscription form, as set forth in the Warrant, duly executed,
and by paying in full the Warrant Price for each share of Common Stock as to which the Warrant is exercised and any and all applicable
taxes due in connection with the exercise of the Warrant, as follows:


 


(a) by good
certified check or good bank draft payable to the order of the Warrant Agent or wire transfer; or


 


(b) in the
event of redemption pursuant to Section 6 hereof in which the Company’s management has elected to force all holders of Warrants
to exercise such Warrants on a “cashless basis,” by surrendering the Warrants for that number of shares of Common Stock
equal to the quotient obtained by dividing (x) the product of the number of shares of Common Stock underlying the Warrants, multiplied
by the difference between the Warrant Price and the “Fair Market Value” (defined below) by (y) the Fair Market Value.
Solely for purposes of this Section 3.3.1(b), the “Fair Market Value” shall mean the average last reported sale
price of the Common Stock for the five (5) trading days ending on the third trading day prior to the date on which the notice of
redemption is sent to holders of the Warrants pursuant to Section 6 hereof; or


 


(c)
with respect to any Private Warrants or Working Capital Warrants, so long as such Private Warrants or Working Capital
Warrants are held by the initial purchasers or their permitted transferees, by surrendering such Private Warrants or Working
Capital Warrants for that number of shares of Common Stock equal to the quotient obtained by dividing (x) the product of the
number of shares of Common Stock underlying the Warrants, multiplied by the difference between the exercise price of the
Warrants and the “Fair Market Value” by (y) the Fair Market Value; provided, however, that no cashless exercise
shall be permitted unless the Fair Market Value is equal to or higher than the exercise price. Solely for purposes of this
Section 3.3.1(c), the “Fair Market Value” shall mean the average reported last sale price of the Common
Stock for the five (5) trading days ending on the third trading day prior to the date of exercise; or


 






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(d) in the
event the registration statement required by Section 7.4 hereof is not effective and current within ninety (90) days after the
closing of a Business Combination, by surrendering such Warrants for that number of shares of Common Stock equal to the quotient
obtained by dividing (x) the product of the number of shares of Common Stock underlying the Warrants, multiplied by the difference
between the exercise price of the Warrants and the “Fair Market Value” by (y) the Fair Market Value; provided, however,
that no cashless exercise shall be permitted unless the Fair Market Value is equal to or higher than the exercise price. Solely
for purposes of this Section 3.3.1(d), the “Fair Market Value” shall mean the average reported last sale price
of the Common Stock for the five (5) trading days ending on the trading day prior to the date of exercise.


 


3.3.2. Issuance
of Shares of Common Stock. As soon as practicable after the exercise of any Warrant and the clearance of the funds in payment
of the Warrant Price (if any), the Company shall issue to the registered holder of such Warrant a certificate or certificates,
or book entry position, for the number of shares of Common Stock to which he, she or it is entitled, registered in such name or
names as may be directed by him, her or it, and if such Warrant shall not have been exercised in full, a new countersigned Warrant,
or book entry position, for the number of shares as to which such Warrant shall not have been exercised. Notwithstanding the foregoing,
in no event will the Company be required to net cash settle the Warrant exercise. No Warrant shall be exercisable for cash and
the Company shall not be obligated to issue shares of Common Stock upon exercise of a Warrant unless the Common Stock issuable
upon such Warrant exercise has been registered, qualified or deemed to be exempt under the securities laws of the state of residence
of the registered holder of the Warrants. In the event that the condition in the immediately preceding sentence is not satisfied
with respect to a Warrant, the holder of such Warrant shall not be entitled to exercise such Warrant for cash and such Warrant
may have no value and expire worthless, in which case the purchaser of a Unit containing such Public Warrants shall have paid the
full purchase price for the Unit solely for the shares of Common Stock underlying such Unit. Warrants may not be exercised by,
or securities issued to, any registered holder in any state in which such exercise would be unlawful.


 


3.3.3. Valid
Issuance. All shares of Common Stock issued upon the proper exercise of a Warrant in conformity with this Agreement shall be
validly issued, fully paid and nonassessable.


 


3.3.4. Date of
Issuance. Each person in whose name any book entry position or certificate for shares of Common Stock is issued shall for all
purposes be deemed to have become the holder of record of such shares on the date on which the Warrant, or book entry position
representing such Warrant, was surrendered and payment of the Warrant Price was made, irrespective of the date of delivery of such
certificate, except that, if the date of such surrender and payment is a date when the share transfer books of the Company or book
entry system of the Warrant Agent are closed, such person shall be deemed to have become the holder of such shares at the close
of business on the next succeeding date on which the share transfer books or book entry system are open.


 






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3.3.5 Maximum
Percentage. A holder of a Warrant may notify the Company in writing in the event it elects to be subject to the
provisions contained in this subsection 3.3.5; however, no holder of a Warrant shall be subject to this subsection 3.3.5
unless he, she or it makes such election. If the election is made by a holder, the Warrant Agent shall not effect the
exercise of the holder’s Warrant, and such holder shall not have the right to exercise such Warrant, to the extent that
after giving effect to such exercise, such person (together with such person’s affiliates), to the Warrant
Agent’s actual knowledge, would beneficially own in excess of 9.8% (the “Maximum Percentage”) of the
shares of Common Stock outstanding immediately after giving effect to such exercise. For purposes of the foregoing sentence,
the aggregate number of shares of Common Stock beneficially owned by such person and its affiliates shall include the number
of shares of Common Stock issuable upon exercise of the Warrant with respect to which the determination of such sentence is
being made, but shall exclude shares of Common Stock that would be issuable upon (x) exercise of the remaining, unexercised
portion of the Warrant beneficially owned by such person and its affiliates and (y) exercise or conversion of the unexercised
or unconverted portion of any other securities of the Company beneficially owned by such person and its affiliates
(including, without limitation, any convertible notes or convertible preferred stock or warrants) subject to a limitation on
conversion or exercise analogous to the limitation contained herein. Except as set forth in the preceding sentence, for
purposes of this paragraph, beneficial ownership shall be calculated in accordance with Section 13(d) of the Securities
Exchange Act of 1934, as amended (the “Exchange Act”). For purposes of the Warrant, in determining the
number of outstanding shares of Common Stock, the holder may rely on the number of outstanding shares of Common Stock as
reflected in (1) the Company’s most recent annual report on Form 10-K, quarterly report on Form 10-Q, current report on
Form 8-K or other public filing with the SEC as the case may be, (2) a more recent public announcement by the Company or (3)
any other notice by the Company or the Warrant Agent setting forth the number of shares of Common Stock outstanding. For any
reason at any time, upon the written request of the holder of the Warrant, the Company shall, within two (2) Business Days,
confirm orally and in writing to such holder the number of shares of Common Stock then outstanding. In any case, the number
of outstanding shares of Common Stock shall be determined after giving effect to the conversion or exercise of equity
securities of the Company by the holder and its affiliates since the date as of which such number of outstanding shares of
Common Stock was reported. By written notice to the Company, the holder of a Warrant may from time to time increase or
decrease the Maximum Percentage applicable to such holder to any other percentage specified in such notice; provided,
however, that any such increase shall not be effective until the sixty-first (61st) day after such notice is delivered to the
Company.


 


4. Adjustments.


 


4.1. Stock
Dividends; Split Ups. If after the date hereof, and subject to the provisions of Section 4.6 below, the number of outstanding
shares of Common Stock is increased by a stock dividend payable in shares of Common Stock, or by a split up of shares of Common
Stock, or other similar event, then, on the effective date of such stock dividend, split up or similar event, the number of shares
of Common Stock issuable on exercise of each Warrant shall be increased in proportion to such increase in outstanding shares of
Common Stock.


 


4.2. Aggregation
of Shares. If after the date hereof, the number of outstanding shares of Common Stock is decreased by a consolidation, combination,
reverse stock split or reclassification of shares of Common Stock or other similar event, then, on the effective date of such consolidation,
combination, reverse stock split, reclassification or similar event, the number of shares of Common Stock issuable on exercise
of each Warrant shall be decreased in proportion to such decrease in outstanding shares of Common Stock.


 


4.3 Extraordinary
Dividends. If the Company, at any time while the Warrants are outstanding and unexpired, shall pay a dividend or make a distribution
in cash, securities or other assets to the holders of the shares of Common Stock or other shares of the Company’s capital
stock into which the Warrants are convertible (an “Extraordinary Dividend”), then the Warrant Price shall be
decreased, effective immediately after the effective date of such Extraordinary Dividend, by the amount of cash and the fair market
value (as determined by the Company’s Board of Directors, in good faith) of any securities or other assets paid on each share
of Common Stock in respect of such Extraordinary Dividend; provided, however, that none of the following shall be deemed an Extraordinary
Dividend for purposes of this provision: (a) any adjustment described in subsection 4.1 above, (b) any cash dividends or cash distributions
which, when combined on a per share basis with all other cash dividends and cash distributions paid on the Common Stock during
the 365-day period ending on the date of declaration of such dividend or distribution does not exceed $0.50 (as adjusted to appropriately
reflect any of the events referred to in other subsections of this Section 4 and excluding cash dividends or cash distributions
that resulted in an adjustment to the Warrant Price or to the number of shares of Common Stock issuable on exercise of each Warrant)
but only with respect to the amount of the aggregate cash dividends or cash distributions equal to or less than $0.50, (c) any
payment to satisfy the conversion rights of the holders of the shares of Common Stock in connection with a proposed initial Business
Combination or (d) any payment in connection with the Company’s liquidation and the distribution of its assets upon its failure
to consummate a Business Combination. Solely for purposes of illustration, if the Company, at a time while the Warrants are outstanding
and unexpired, pays a cash dividend of $0.35 and previously paid an aggregate of $0.40 of cash dividends and cash distributions
on the Common Stock during the 365-day period ending on the date of declaration of such $0.35 dividend, then the Warrant Price
will be decreased, effectively immediately after the effective date of such $0.35 dividend, by $0.25 (the absolute value of the
difference between $0.75 (the aggregate amount of all cash dividends and cash distributions paid or made in such 365-day period,
including such $0.35 dividend) and $0.50 (the greater of (x) $0.50 and (y) the aggregate amount of all cash dividends and cash
distributions paid or made in such 365-day period prior to such $0.35 dividend)).


 






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4.4 Adjustments
in Exercise Price. Whenever the number of shares of Common Stock purchasable upon the exercise of the Warrants is
adjusted, as provided in Sections 4.1 and 4.2 above, the Warrant Price shall be adjusted (to the nearest cent) by multiplying
such Warrant Price immediately prior to such adjustment by a fraction (x) the numerator of which shall be the number of
shares of Common Stock purchasable upon the exercise of the Warrants immediately prior to such adjustment, and (y) the
denominator of which shall be the number of shares of Common Stock so purchasable immediately thereafter. 


 


4.5. Replacement
of Securities upon Reorganization, etc. In case of any reclassification or reorganization of the outstanding shares of Common
Stock (other than a change covered by Section 4.1, 4.2 or 4.3 hereof or that solely affects the par value of the Common Stock),
or in the case of any merger or consolidation of the Company with or into another corporation (other than a consolidation or merger
in which the Company is the continuing corporation and that does not result in any reclassification or reorganization of the outstanding
Common Stock), or in the case of any sale or conveyance to another corporation or entity of the assets or other property of the
Company as an entirety or substantially as an entirety in connection with which the Company is dissolved, the Warrant holders shall
thereafter have the right to purchase and receive, upon the basis and upon the terms and conditions specified in the Warrants and
in lieu of the shares of Common Stock of the Company immediately theretofore purchasable and receivable upon the exercise of the
rights represented thereby, the kind and amount of shares of stock or other securities or property (including cash) receivable
upon such reclassification, reorganization, merger or consolidation, or upon a dissolution following any such sale or transfer,
that the Warrant holder would have received if such Warrant holder had exercised his, her or its Warrant(s) immediately prior to
such event. If any reclassification also results in a change in the Common Stock covered by Section 4.1, 4.2 or 4.3, then such
adjustment shall be made pursuant to Sections 4.1, 4.2, 4.3, 4.4 and this Section 4.5. The provisions of this Section 4.5 shall
similarly apply to successive reclassifications, reorganizations, mergers or consolidations, sales or other transfers. In no event
will the Warrant Price be reduced to less than the par value per share issuable upon exercise of the Warrant.


 


4.6 Issuance in
connection with a Business Combination. If, in connection with a Business Combination, the Company (a) issues additional shares
of Common Stock or equity-linked securities at an issue price or effective issue price of less than $9.50 per share (with such
issue price or effective issue price as determined by the Company’s Board of Directors, in good faith, and in the case of
any such issuance to Petra Investment Holdings, LLC, the initial stockholders, or their affiliates, without taking into account
any founders’ shares held by them prior to such issuance), (y) the aggregate gross proceeds from such issuances represent
more than 60% of the total equity proceeds, and interest thereon, available for the funding of the Business Combination on the
date of the consummation of such Business Combination (net of redemptions), and (z) the Fair Market Value (as defined below) is
below $9.50 per share, the exercise price of the warrants will be adjusted (to the nearest cent) to be equal to 115% of the greater
of (i) the Fair Market Value or (ii) the price at which the Company issues the Common Stock or equity-linked securities. Solely
for purposes of this Section 4.6, the “Fair Market Value” shall mean the average reported last sale price of
the Common Stock for the five (5) trading days ending on the trading day prior to the issuance of Common Stock or equity-linked
securities.


 


4.7. Notices
of Changes in Warrant. Upon every adjustment of the Warrant Price or the number of shares issuable upon exercise of a Warrant,
the Company shall give written notice thereof to the Warrant Agent, which notice shall state the Warrant Price resulting from such
adjustment and the increase or decrease, if any, in the number of shares purchasable at such price upon the exercise of a Warrant,
setting forth in reasonable detail the method of calculation and the facts upon which such calculation is based. Upon the occurrence
of any event specified in Sections 4.1, 4.2, 4.3, 4.4, 4.5, or 4.6, then, in any such event, the Company shall give written notice
to each Warrant holder, at the last address set forth for such holder in the Warrant Register, of the record date or the effective
date of the event. Failure to give such notice, or any defect therein, shall not affect the legality or validity of such event.


 


4.8. No Fractional
Warrants or Shares. Notwithstanding any provision contained in this Agreement to the contrary, the Company shall not issue
fractional shares upon exercise of Warrants. If, by reason of any adjustment made pursuant to this Section 4, the holder of any
Warrant would be entitled, upon the exercise of such Warrant, to receive a fractional interest in a share, the Company shall, upon
such exercise, round up to the nearest whole number of shares of Common Stock to be issued to the Warrant holder.


 






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4.9. Form
of Warrant. The form of Warrant need not be changed because of any adjustment pursuant to this Section 4, and Warrants
issued after such adjustment may state the same Warrant Price and the same number of shares as is stated in the Warrants
initially issued pursuant to this Agreement. However, the Company may at any time in its sole discretion make any change in
the form of Warrant that the Company may deem appropriate and that does not affect the substance thereof, and any Warrant
thereafter issued or countersigned, whether in exchange or substitution for an outstanding Warrant or otherwise, may be in
the form as so changed.


  


4.10 Other
Events. In case any event shall occur affecting the Company as to which none of the provisions of preceding subsections of
this Section 4 are strictly applicable, but which would require an adjustment to the terms of the Warrants in order to (i) avoid
an adverse impact on the Warrants and (ii) effectuate the intent and purpose of this Section 4, then, in each such case, the Company
shall appoint a firm of independent public accountants, investment banking or other appraisal firm of recognized national standing,
which shall give its opinion as to whether or not any adjustment to the rights represented by the Warrants is necessary to effectuate
the intent and purpose of this Section 4 and, if they determine that an adjustment is necessary, the terms of such adjustment.
The Company shall adjust the terms of the Warrants in a manner that is consistent with any adjustment recommended in such opinion.


 


5. Transfer and Exchange of Warrants.


 


5.1. Registration
of Transfer. The Warrant Agent shall register the transfer, from time to time, of any outstanding Warrant upon the Warrant
Register, upon surrender of such Warrant for transfer, properly endorsed with signatures, in the case of certificated Warrants,
properly guaranteed and accompanied by appropriate instructions for transfer. Upon any such transfer, a new Warrant representing
an equal aggregate number of Warrants shall be issued and the old Warrant shall be cancelled by the Warrant Agent. In the case
of certificated Warrants, the Warrants so cancelled shall be delivered by the Warrant Agent to the Company from time to time upon
request.


 


5.2. Procedure
for Surrender of Warrants. Warrants may be surrendered to the Warrant Agent, either in certificated form or in book entry position,
together with a written request for exchange or transfer, and thereupon the Warrant Agent shall issue in exchange therefor one
or more new Warrants, or book entry positions, as requested by the registered holder of the Warrants so surrendered, representing
an equal aggregate number of Warrants; provided, however, that in the event that a Warrant surrendered for transfer bears a restrictive
legend, the Warrant Agent shall not cancel such Warrant and issue new Warrants in exchange therefor until the Warrant Agent has
received an opinion of counsel for the Company stating that such transfer may be made and indicating whether the new Warrants must
also bear a restrictive legend.


 


5.3. Fractional
Warrants. The Warrant Agent shall not be required to effect any registration of transfer or exchange which will result in the
issuance of a warrant certificate or book-entry position for a fraction of a warrant.


 


5.4. Service
Charges. No service charge shall be made for any exchange or registration of transfer of Warrants.


 


5.5. Warrant
Execution and Countersignature. The Warrant Agent is hereby authorized to countersign and to deliver, in accordance with the
terms of this Agreement, the Warrants required to be issued pursuant to the provisions of this Section 5, and the Company, whenever
required by the Warrant Agent, will supply the Warrant Agent with Warrants duly executed on behalf of the Company for such purpose.


 


5.6. Private
Warrants. The Warrant Agent shall not register any transfer of Private Warrants or Working Capital Warrants until after
the consummation by the Company of an initial Business Combination, except for transfers (i) among the initial stockholders
or to the initial stockholders’ or the Company’s officers, directors, consultants or their affiliates, (ii) to a
holder’s stockholders or members upon the holder’s liquidation, in each case if the holder is an entity, (iii) by
bona fide gift to a member of the holder’s immediate family or to a trust, the beneficiary of which is the holder or a
member of the holder’s immediate family, in each case for estate planning purposes, (iv) by virtue of the laws of
descent and distribution upon death, (v) pursuant to a qualified domestic relations order, (vi) to the Company for no value
for cancellation in connection with the consummation of a Business Combination, (vii) in connection with the consummation of
a Business Combination by private sales at prices no greater than the price at which the Private Warrants were originally
purchased, (viii) in the event of the Company’s liquidation prior to its consummation of an initial Business
Combination or (ix) in the event that, subsequent to the consummation of an initial Business Combination, the Company
completes a liquidation, merger, share exchange or other similar transaction which results in all of the Company’s
stockholders having the right to exchange their Common Stock for cash, securities or other property, in each case (except for
clauses (vi), (viii) or (ix) or with the Company’s prior written consent) on the condition that prior to such
registration for transfer, the Warrant Agent shall be presented with written documentation pursuant to which each transferee
or the trustee or legal guardian for such transferee agrees to be bound by the terms of the Subscription Agreement and any
other applicable agreement the transferor is bound by. 


  






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5.7. Transfers
prior to Detachment. Prior to the Detachment Date, the Public Warrants may be transferred or exchanged only together with the
Unit in which such Warrant is included, and only for the purpose of effecting, or in conjunction with, a transfer or exchange of
such Unit. Furthermore, each transfer of a Unit on the register relating to such Units shall operate also to transfer the Warrants
included in such Unit. Notwithstanding the foregoing, the provisions of this Section 5.7 shall have no effect on any transfer of
Warrants on or after the Detachment Date.


 


6. Redemption.


 


6.1. Redemption.
Subject to Section 6.4 hereof, not less than all of the outstanding Warrants may be redeemed, at the option of the Company, at
any time during the Exercise Period, at the office of the Warrant Agent, upon the notice referred to in Section 6.2, at the price
of $0.01 per Warrant (“Redemption Price”), provided that the last sales price of the Common Stock equals or
exceeds $18.00 per share (subject to adjustment in accordance with Section 4 hereof), on each of twenty (20) trading days within
any thirty (30) trading day period ending on the third trading day prior to the date on which notice of redemption is given and
provided that there is an effective registration statement covering the shares of Common Stock issuable upon exercise of the Warrants,
and a current prospectus relating thereto, available throughout the 30-day redemption or the Company has elected to require the
exercise of the Warrants on a “cashless basis” pursuant to subsection 3.3.1(b); provided, however, that if and when
the Public Warrants become redeemable by the Company, the Company may not exercise such redemption right if the issuance of shares
of Common Stock upon exercise of the Public Warrants is not exempt from registration or qualification under applicable state blue
sky laws or the Company is unable to effect such registration or qualification.


  


6.2. Date Fixed
for, and Notice of, Redemption. In the event the Company shall elect to redeem all of the Warrants that are subject to redemption,
the Company shall fix a date for the redemption (the “Redemption Date”). Notice of redemption shall be mailed
by first class mail, postage prepaid, by the Company not less than thirty (30) days prior to the Redemption Date to the registered
holders of the Warrants to be redeemed at their last addresses as they shall appear on the registration books. Any notice mailed
in the manner herein provided shall be conclusively presumed to have been duly given whether or not the registered holder received
such notice.


 


6.3. Exercise
After Notice of Redemption. The Public Warrants may be exercised, for cash (or on a “cashless basis” in accordance
with Section 3 of this Agreement) at any time after notice of redemption shall have been given by the Company pursuant to Section
6.2 hereof and prior to the Redemption Date. In the event the Company determines to require all holders of Public Warrants to exercise
their Warrants on a “cashless basis” pursuant to Section 3.3.1(b), the notice of redemption will contain the information
necessary to calculate the number of shares of Common Stock to be received upon exercise of the Warrants, including the “Fair
Market Value” in such case. On and after the Redemption Date, the record holder of the Warrants shall have no further rights
except to receive, upon surrender of the Warrants, the Redemption Price.


 


6.4 Exclusion
of Certain Warrants. The Company agrees that the redemption rights provided in this Section 6 shall not apply to (i) the Private
Warrants and Working Capital Warrants if at the time of the redemption such Private Warrants or Working Capital Warrants continue
to be held by the initial purchasers or their permitted transferees or (ii) Post IPO Warrants if such warrants provide that they
are non-redeemable by the Company. However, with respect to the Private Warrants or Working Capital Warrants, once such Private
Warrants or Working Capital Warrants are transferred (other than to permitted transferees under Section 5.6), the Company may redeem
the Private Warrants and Working Capital Warrants in the same manner as the Public Warrants.


 






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7. Other Provisions Relating to Rights of Holders of
Warrants.


 


7.1. No Rights
as Stockholder. A Warrant does not entitle the registered holder thereof to any of the rights of a stockholder of the Company,
including, without limitation, the right to receive dividends, or other distributions, exercise any preemptive rights to vote or
to consent or to receive notice as stockholders in respect of the meetings of stockholders or the election of directors of the
Company or any other matter.


 


7.2. Lost,
Stolen, Mutilated, or Destroyed Warrants. If any Warrant is lost, stolen, mutilated, or destroyed, the Company and the Warrant
Agent may on such terms as to indemnity or otherwise as they may in their discretion impose (which shall, in the case of a mutilated
Warrant, include the surrender thereof), issue a new Warrant of like denomination, tenor, and date as the Warrant so lost, stolen,
mutilated, or destroyed. Any such new Warrant shall constitute a substitute contractual obligation of the Company, whether or not
the allegedly lost, stolen, mutilated, or destroyed Warrant shall be at any time enforceable by anyone. 


 


7.3. Reservation
of Shares of Common Stock. The Company shall at all times reserve and keep available a number of its authorized but unissued
shares of Common Stock that will be sufficient to permit the exercise in full of all outstanding Warrants issued pursuant to this
Agreement.


 


7.4. Registration
of Shares of Common Stock. The Company agrees that as soon as practicable after the closing of its initial Business Combination,
it shall use its best efforts to file with the Securities and Exchange Commission a registration statement for the registration,
under the Act, of the shares of Common Stock issuable upon exercise of the Warrants, and it shall use its best efforts to take
such action as is necessary to register or qualify for sale, in those states in which the Warrants were initially offered by the
Company and in those states where holders of Warrants then reside, the shares of Common Stock issuable upon exercise of the Warrants,
to the extent an exemption is not available. The Company will use its best efforts to cause the same to become effective and to
maintain the effectiveness of such registration statement until the expiration of the Warrants in accordance with the provisions
of this Agreement. If any such registration statement has not been declared effective by the 90th day following the closing of
the Business Combination, holders of the Warrants shall have the right, during the period beginning on the 91st day after the closing
of the Business Combination and ending upon such registration statement being declared effective by the Securities and Exchange
Commission, and during any other period when the Company shall fail to have maintained an effective registration statement covering
the shares of Common Stock issuable upon exercise of the Warrants, to exercise such Warrants on a “cashless basis”
as determined in accordance with Section 3.3.1(d). The Company shall provide the Warrant Agent with an opinion of counsel for the
Company (which shall be an outside law firm with securities law experience) stating that (i) the exercise of the Warrants on a
cashless basis in accordance with this Section 7.4 is not required to be registered under the Act and (ii) the shares of Common
Stock issued upon such exercise will be freely tradable under U.S. federal securities laws by anyone who is not an affiliate (as
such term is defined in Rule 144 under the Act) of the Company and, accordingly, will not be required to bear a restrictive legend.
For the avoidance of any doubt, unless and until all of the Warrants have been exercised on a cashless basis, the Company shall
continue to be obligated to comply with its registration obligations under the first three sentences of this Section 7.4. The provisions
of this Section 7.4 may not be modified, amended or deleted without the prior written consent of the Representatives.


 


8. Concerning the Warrant Agent and Other Matters.


 


8.1. Payment
of Taxes. The Company will from time to time promptly pay all taxes and charges that may be imposed upon the Company or the
Warrant Agent in respect of the issuance or delivery of shares of Common Stock upon the exercise of Warrants, but the Company shall
not be obligated to pay any transfer taxes in respect of the Warrants or such shares.


 






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8.2. Resignation,
Consolidation, or Merger of Warrant Agent.


 


8.2.1. Appointment
of Successor Warrant Agent. The Warrant Agent, or any successor to it hereafter appointed, may resign its duties and be
discharged from all further duties and liabilities hereunder after giving sixty (60) days’ notice in writing to the
Company. If the office of the Warrant Agent becomes vacant by resignation or incapacity to act or otherwise, the Company
shall appoint in writing a successor Warrant Agent in place of the Warrant Agent. If the Company shall fail to make such
appointment within a period of thirty (30) days after it has been notified in writing of such resignation or incapacity by
the Warrant Agent or by the holder of the Warrant (who shall, with such notice, submit his Warrant for inspection by the
Company), then the holder of any Warrant may apply to the Supreme Court of the State of New York for the County of New York
for the appointment of a successor Warrant Agent at the Company’s cost. Any successor Warrant Agent, whether appointed
by the Company or by such court, shall be a corporation organized and existing under the laws of the State of New York, in
good standing and having its principal office in the Borough of Manhattan, City and State of New York, and authorized under
such laws to exercise corporate trust powers and subject to supervision or examination by federal or state authority. After
appointment, any successor Warrant Agent shall be vested with all the authority, powers, rights, immunities, duties, and
obligations of its predecessor Warrant Agent with like effect as if originally named as Warrant Agent hereunder, without any
further act or deed; but if for any reason it becomes necessary or appropriate, the predecessor Warrant Agent shall execute
and deliver, at the expense of the Company, an instrument transferring to such successor Warrant Agent all the authority,
powers, and rights of such predecessor Warrant Agent hereunder; and upon request of any successor Warrant Agent the Company
shall make, execute, acknowledge, and deliver any and all instruments in writing for more fully and effectually vesting in
and confirming to such successor Warrant Agent all such authority, powers, rights, immunities, duties, and
obligations. 


 


8.2.2. Notice
of Successor Warrant Agent. In the event a successor Warrant Agent shall be appointed, the Company shall give notice thereof
to the predecessor Warrant Agent and the transfer agent for the shares of Common Stock not later than the effective date of any
such appointment.


 


8.2.3. Merger
or Consolidation of Warrant Agent. Any corporation into which the Warrant Agent may be merged or with which it may be consolidated
or any corporation resulting from any merger or consolidation to which the Warrant Agent shall be a party shall be the successor
Warrant Agent under this Agreement without any further act.


 


8.3. Fees and
Expenses of Warrant Agent.


 


8.3.1. Remuneration.
The Company agrees to pay the Warrant Agent reasonable remuneration for its services as such Warrant Agent hereunder and will reimburse
the Warrant Agent upon demand for all expenditures that the Warrant Agent may reasonably incur in the execution of its duties hereunder.


 


8.3.2. Further
Assurances. The Company agrees to perform, execute, acknowledge, and deliver or cause to be performed, executed, acknowledged,
and delivered all such further and other acts, instruments, and assurances as may reasonably be required by the Warrant Agent for
the carrying out or performing of the provisions of this Agreement.


 


8.4. Liability
of Warrant Agent.


 


8.4.1. Reliance
on Company Statement. Whenever in the performance of its duties under this Agreement, the Warrant Agent shall deem it necessary
or desirable that any fact or matter be proved or established by the Company prior to taking or suffering any action hereunder,
such fact or matter (unless other evidence in respect thereof be herein specifically prescribed) may be deemed to be conclusively
proved and established by a statement signed by the Chief Executive Officer or Chairman of the Board of Directors of the Company
and delivered to the Warrant Agent. The Warrant Agent may rely upon such statement for any action taken or suffered in good faith
by it pursuant to the provisions of this Agreement.


 


8.4.2. Indemnity.
The Warrant Agent shall be liable hereunder only for its own fraud, gross negligence, willful misconduct or bad faith. The Company
agrees to indemnify the Warrant Agent and save it harmless against any and all liabilities, including judgments, costs and reasonable
counsel fees, for anything done or omitted by the Warrant Agent in the execution of this Agreement except as a result of the Warrant
Agent’s fraud, gross negligence, willful misconduct, or bad faith.


 


8.4.3. Exclusions.
The Warrant Agent shall have no responsibility with respect to the validity of this Agreement or with respect to the validity
or execution of any Warrant (except its countersignature thereof); nor shall it be responsible for any breach by the Company
of any covenant or condition contained in this Agreement or in any Warrant; nor shall it be responsible to make any
adjustments required under the provisions of Section 4 hereof or responsible for the manner, method, or amount of any such
adjustment or the ascertaining of the existence of facts that would require any such adjustment; nor shall it by any act
hereunder be deemed to make any representation or warranty as to the authorization or reservation of any shares of Common
Stock to be issued pursuant to this Agreement or any Warrant or as to whether any shares of Common Stock will, when issued,
be valid and fully paid and nonassessable.


 






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8.5. Acceptance
of Agency. The Warrant Agent hereby accepts the agency established by this Agreement and agrees to perform the same upon the
terms and conditions herein set forth and among other things, shall account promptly to the Company with respect to Warrants exercised
and concurrently account for, and pay to the Company, all monies received by the Warrant Agent for the purchase of shares of Common
Stock through the exercise of Warrants.


  


9. Miscellaneous Provisions.


 


9.1. Successors.
All the covenants and provisions of this Agreement by or for the benefit of the Company or the Warrant Agent shall bind and inure
to the benefit of their respective successors and assigns.


 


9.2. Notices.
Any notice, statement or demand authorized by this Agreement to be given or made by the Warrant Agent or by the holder of any Warrant
to or on the Company shall be sufficiently given when so delivered if by hand or overnight delivery or if sent by certified mail
or private courier service within five (5) days after deposit of such notice, postage prepaid, addressed (until another address
is filed in writing by the Company with the Warrant Agent), as follows:


 


Petra Acquisition, Inc.


5 West 21st Street


New York, NY 10010


Attn: Andreas Typaldos, CEO


 


Any notice, statement or demand authorized
by this Agreement to be given or made by the holder of any Warrant or by the Company to or on the Warrant Agent shall be sufficiently
given when so delivered if by hand or overnight delivery or if sent by certified mail or private courier service within five days
after deposit of such notice, postage prepaid, addressed (until another address is filed in writing by the Warrant Agent with the
Company), as follows:


 


Continental Stock Transfer & Trust Company


1 State Street


New York, New York 10004


Attn: Compliance Department


 


with a copy in each case to:


 


Horwitz + Armstrong, APLC


14 Orchard, Suite 200


Lake Forest, CA 92630


Attn: Lawrence W. Horwitz, Esq.


 


and


 


Ellenoff Grossman & Schole LLP


1345 Avenue of the Americas


New York, New York 10105


Attn: Stuart Neuhauser, Esq.


 


and


 


LifeSci Capital LLC


250 West 55th Street,
Suite 3401


New York, NY 10019


Attn: David Dobkin, Managing Director


 






    11


     


    

 


and




Ladenburg Thalmann & Co.


277 Park Avenue, 26th Floor


New York, NY 10172


Attn: Steven Kaplan, Head of
Capital Markets


 


9.3. Applicable
Law. The validity, interpretation, and performance of this Agreement and of the Warrants shall be governed in all respects
by the laws of the State of New York, without giving effect to conflicts of law principles that would result in the application
of the substantive laws of another jurisdiction. The Company hereby agrees that any action, proceeding or claim against it arising
out of or relating in any way to this Agreement shall be brought and enforced in the courts of the State of New York or the United
States District Court for the Southern District of New York, and irrevocably submits to such jurisdiction, which jurisdiction shall
be exclusive. The Company hereby waives any objection to such exclusive jurisdiction and that such courts represent an inconvenient
forum. Any such process or summons to be served upon the Company may be served by transmitting a copy thereof by registered or
certified mail, return receipt requested, postage prepaid, addressed to it at the address set forth in Section 9.2 hereof. Such
mailing shall be deemed personal service and shall be legal and binding upon the Company in any action, proceeding or claim.


 


9.4. Persons
Having Rights under this Agreement. Nothing in this Agreement expressed and nothing that may be implied from any of the provisions
hereof is intended, or shall be construed, to confer upon, or give to, any person or corporation other than the parties hereto
and the registered holders of the Warrants and, for the purposes of Sections 7.4, 9.4 and 9.8 hereof, the Representatives, any
right, remedy, or claim under or by reason of this Warrant Agreement or of any covenant, condition, stipulation, promise, or agreement
hereof. LifeSci Capital shall be deemed to be a third-party beneficiary of this Agreement with respect to Sections 7.4, 9.4 and
9.8 hereof. All covenants, conditions, stipulations, promises, and agreements contained in this Warrant Agreement shall be for
the sole and exclusive benefit of the parties hereto (and the Representatives with respect to the Sections 7.4, 9.4 and 9.8 hereof)
and their successors and assigns and of the registered holders of the Warrants.


 


9.5. Examination
of the Warrant Agreement. A copy of this Agreement shall be available at all reasonable times at the office of the Warrant
Agent in the Borough of Manhattan, City and State of New York, for inspection by the registered holder of any Warrant. The Warrant
Agent may require any such holder to submit his Warrant for inspection by it.


 


9.6. Counterparts.
This Agreement may be executed in any number of original or facsimile counterparts and each of such counterparts shall for all
purposes be deemed to be an original, and all such counterparts shall together constitute but one and the same instrument.


 


9.7. Effect
of Headings. The section headings herein are for convenience only and are not part of this Agreement and shall not affect the
interpretation thereof.


 


9.8 Amendments.
This Agreement may be amended by the parties hereto without the consent of any registered holder for the purpose of curing any
ambiguity, or of curing, correcting or supplementing any defective provision contained herein or adding or changing any other provisions
with respect to matters or questions arising under this Agreement as the parties may deem necessary or desirable and that the parties
deem shall not adversely affect the interest of the registered holders. All other modifications or amendments, including any amendment
to increase the Warrant Price or shorten the Exercise Period, shall require the written consent or vote of the registered holders
of a majority of the then outstanding Public Warrants. Notwithstanding the foregoing, the Company may lower the Warrant Price or
extend the duration of the Exercise Period pursuant to Sections 3.1 and 3.2, respectively, without the consent of the registered
holders. The provisions of this Section 9.8 may not be modified, amended or deleted without the prior written consent of the Representatives.


 






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9.9 Trust
Account Waiver. The Warrant Agent acknowledges and agrees that it shall not make any claims or proceed against the trust account
established by the Company in connection with the Public Offering (as more fully described in the Registration Statement) (“Trust
Account”), including by way of set-off, and shall not be entitled to any funds in the Trust Account under any circumstance.
In the event that the Warrant Agent has a claim against the Company under this Agreement, the Warrant Agent will pursue such claim
solely against the Company and not against the property held in the Trust Account.





 


9.10 Severability.
This Agreement shall be deemed severable, and the invalidity or unenforceability of any term or provision hereof shall not affect
the validity or enforceability of this Agreement or of any other term or provision hereof. Furthermore, in lieu of any such invalid
or unenforceable term or provision, the parties hereto intend that there shall be added as a part of this Agreement a provision
as similar in terms to such invalid or unenforceable provision as may be possible and be valid and enforceable.


 


[Signature Page Follows]


 






    13


     


    

  


IN WITNESS WHEREOF,
this Agreement has been duly executed by the parties hereto as of the day and year first above written.


 


	 	PETRA ACQUISITION, INC.
	 	 	 	 
	 	By:	/s/
Andreas Typaldos
	 	 	Name:	 Andreas Typaldos
	 	 	Title:	 CEO
	 	 	 	 
	 	CONTINENTAL STOCK TRANSFER &

TRUST COMPANY
	 	 	 	 
	 	By:	/s/
    Stacy Aqui
	 	 	Name:	 Stacy Aqui
	 	 	Title:	 Vice President