Exhibit 4.3


 


THE REGISTERED HOLDER OF
THIS PURCHASE WARRANT BY ITS ACCEPTANCE HEREOF, AGREES THAT IT WILL NOT SELL, TRANSFER OR ASSIGN THIS PURCHASE WARRANT EXCEPT AS HEREIN
PROVIDED AND THE REGISTERED HOLDER OF THIS PURCHASE WARRANT AGREES THAT IT WILL NOT SELL, TRANSFER, ASSIGN, PLEDGE OR HYPOTHECATE THIS
PURCHASE WARRANT FOR A PERIOD OF ONE HUNDRED EIGHTY DAYS FOLLOWING [●], 20[●] (THE “EFFECTIVE DATE”) TO
ANYONE OTHER THAN (I) [●] OR A SELECTED DEALER IN CONNECTION WITH THE OFFERING FOR WHICH THIS PURCHASE WARRANT WAS ISSUED TO THE
UNDERWRITER AS CONSIDERATION (THE “OFFERING”), OR (II) A BONA FIDE OFFICER OR PARTNER OF [●].


 


THIS PURCHASE WARRANT IS
NOT EXERCISABLE PRIOR TO [●], 2022. VOID AFTER 5:00 P.M., EASTERN TIME, [●], 202_.


 


COMMON STOCK PURCHASE WARRANT


 


For the Purchase of [●] Shares of Common
Stock


 


of


 


PaxMedica, Inc.


 


1.       Purchase
Warrant. THIS CERTIFIES THAT, in consideration of funds duly paid by or on behalf of [●] (“Holder”), as
registered owner of this Purchase Warrant, to PaxMedica, Inc., a Delaware corporation (the “Company”), Holder is entitled,
at any time or from time to time beginning [●], 202_ (the “Commencement Date”), and at or before 5:00 p.m.,
Eastern time, [●], 202_1 (the “Expiration Date”), but not thereafter, to subscribe
for, purchase and receive, in whole or in part, up to [●] shares of common stock of the Company, par value $0.0001 per share (the
 “Shares”), subject to adjustment as provided in Section 6 hereof. If the Expiration Date is a day on which banking
institutions are authorized by law to close, then this Purchase Warrant may be exercised on the next succeeding day which is not such
a day in accordance with the terms herein. During the period ending on the Expiration Date, the Company agrees not to take any action
that would terminate this Purchase Warrant. This Purchase Warrant is initially exercisable at $[●] per Share2; provided, however,
that upon the occurrence of any of the events specified in Section 6 hereof, the rights granted by this Purchase Warrant, including the
exercise price per Share and the number of Shares to be received upon such exercise, shall be adjusted as therein specified. The term
 “Exercise Price” shall mean the initial exercise price or the adjusted exercise price, depending on the context.


 


2.       Exercise.


 


2.1       Exercise
Form. In order to exercise this Purchase Warrant, the exercise form attached hereto must be duly executed and completed and delivered
to the Company, together with this Purchase Warrant and payment of the Exercise Price for the Shares being purchased payable in cash
by wire transfer of immediately available funds to an account designated by the Company or by certified check or official bank check.
If the subscription rights represented hereby shall not be exercised at or before 5:00 p.m., Eastern time, on the Expiration Date, this
Purchase Warrant shall become and be void without further force or effect, and all rights represented hereby shall cease and expire.
Each exercise hereof shall be irrevocable.


 


1 [To be 4.5 years from 6 months
following the S-1 offering closing date.]


2 [To be 125% of the public offering
price per Share]


 






    


    


    

 


2.2       Cashless
Exercise. In lieu of exercising this Purchase Warrant by payment of cash or check payable to the order of the Company pursuant
to Section 2.1 above, Holder may elect to receive the number of Shares equal to the value of this Purchase Warrant (or the portion thereof
being exercised), by surrender of this Purchase Warrant to the Company, together with the exercise form attached hereto, in which event
the Company will issue to Holder Shares in accordance with the following formula:


	X	=	 

                                                                                Y(A-B)
	 
	A	 
	 	 	 	 
	Where,	 	 	 
	 	X	=	The number of Shares to
    be issued to Holder;
	 	Y	=	The number of Shares for
    which the Purchase Warrant is being exercised;
	 	A	=	The fair market value
    of one Share; and
	 	B	=	The Exercise Price.


  


For purposes of this Section
2.2, the fair market value means, for any date, the price determined by the first of the following clauses that applies: (a) if the common
stock is then listed or quoted on an Eligible Market (as such term is defined below), the value shall be deemed to be the closing price
on such Eligible Market on which the common stock is then listed or quoted as reported by Bloomberg L.P. on the day immediately prior
to the exercise form being submitted in connection with the exercise of the Purchase Warrant, (b) if the common stock is not then listed
or quoted on an Eligible Market but is then quoted on the OTCQB or OTCQX, the value shall be deemed to be the closing bid price on the
OTCQB or OTCQX on which the common stock is then quoted as reported by Bloomberg L.P. on the day immediately prior to the exercise form
being submitted in connection with the exercise of the Purchase Warrant, (c) if the common stock is not then listed or quoted for trading
on the OTCQB or OTCQX and if prices for the common stock are then reported in the “Pink Sheets” published by OTC Markets
Group, Inc. (or a similar organization or agency succeeding to its functions of reporting prices), the “OTC Markets Group”,
the value shall be deemed to be the closing bid price on the day immediately prior to the exercise form being submitted in connection
with the exercise of the Purchase Warrant, or (d) in all other cases, the fair market value of a share of common stock as determined
in good faith by the Company’s Board of Directors. “Eligible Market” means The New York Stock Exchange, the NYSE American,
the Nasdaq Global Select Market, the Nasdaq Global Market or the Nasdaq Capital Market.


 


2.3        Legend.
Each certificate for the securities purchased under this Purchase Warrant shall bear a legend as follows unless such securities have
been registered under the Securities Act of 1933, as amended (the “Act”):


 


“The securities represented
by this certificate have not been registered under the Securities Act of 1933, as amended (the “Act”), or applicable
state law. Neither the securities nor any interest therein may be offered for sale, sold or otherwise transferred except pursuant to
an effective registration statement under the Act, or pursuant to an exemption from registration under the Act and applicable state law
which, in the opinion of counsel to the Company, is available.”


 






    


    


    

 


2.4       Resale
of Shares. Holder and the Company acknowledge that as of the date hereof the Staff of the Division of Corporation Finance of the
SEC has published Compliance & Disclosure Interpretation 528.04 in the Securities Act Rules section thereof, stating that the holder
of securities issued in connection with a public offering may not rely upon Rule 144 promulgated under the Act to establish an exemption
from registration requirements under Section 4(a)(1) under the Act, but may nonetheless apply Rule 144 constructively for the resale
of such shares in the following manner: (a) provided that six months has elapsed since the last sale under the registration statement,
an underwriter or finder may resell the securities in accordance with the provisions of Rule 144(c), (e), and (f), except for the notice
requirement; (b) a purchaser of the shares from an underwriter receives restricted securities unless the sale is made with an appropriate,
current prospectus, or unless the sale is made pursuant to the conditions contained in (a) above; (c) a purchaser of the shares from
an underwriter who receives restricted securities may include the underwriter’s holding period, provided that the underwriter or
finder is not an affiliate of the issuer; and (d) if an underwriter transfers the shares to its employees, the employees may tack the
firm’s holding period for purposes of Rule 144(d), but they must aggregate sales of the distributed shares with those of other
employees, as well as those of the underwriter or finder, for a six-month period from the date of the transfer to the employees. Holder
and the Company also acknowledge that the Staff of the Division of Corporation Finance of the SEC has advised in various no-action letters
that the holding period associated with securities issued without registration to a service provider commences upon the completion of
the services, which the Company agrees and acknowledges shall be the final closing of the Offering, and that Rule 144(d)(3)(ii) provides
that securities acquired from the issuer solely in exchange for other securities of the same issuer shall be deemed to have been acquired
at the same time as the securities surrendered for conversion (which the Company agrees is the date of the initial issuance of this Purchase
Warrant). In the event that following a reasonably-timed written request by Holder to transfer the Shares in accordance with Compliance
 & Disclosure Interpretation 528.04 counsel for the Company in good faith concludes that Compliance & Disclosure Interpretation
528.04 no longer may be relied upon as a result of changes in applicable laws, regulations, or interpretations of the SEC Division of
Corporation Finance, or as a result of judicial interpretations not known by the Company or its counsel on the date hereof, then the
Company shall promptly, and in any event within five (5) business days following the request, provide written notice to Holder of such
determination. As a condition to giving such notice, the parties shall negotiate in good faith a single demand registration right pursuant
to an agreement in customary form reasonably acceptable to the parties; provided that notwithstanding anything to the contrary, the obligations
of the Company pursuant to this Section 2 shall terminate on the fifth anniversary of the Effective Date. In the absence of such conclusion
by counsel for the Company, the Company shall, upon such a request of Holder given no earlier than six months after the final closing
of the Offering, instruct its transfer agent to permit the transfer of such shares in accordance with Compliance & Disclosure Interpretation
528.04, provided that Holder has provided such documentation as shall be reasonably be requested by the Company to establish compliance
with the conditions of Compliance & Disclosure Interpretation 528.04. Notwithstanding anything to the contrary, pursuant to FINRA
Rule 5110(g)(8)(B)-(D), the Holder shall not be entitled to more than one demand registration right hereunder and the duration of the
registration rights hereunder shall not exceed five years from the Effective Date.


 


3.       Transfer.


 


3.1       General
Restrictions. The registered Holder of this Purchase Warrant agrees by his, her or its acceptance hereof, that such Holder will not
for a period of one hundred eighty (180) days following the Effective Date: (a) sell, transfer, assign, pledge or hypothecate this Purchase
Warrant to anyone other than: (i) [●] or an underwriter, placement agent, or a selected dealer participating in the Offering, or
(ii) a bona fide officer or partner of [●] or of any such underwriter, placement agent or selected dealer, in each case in accordance
with FINRA Conduct Rule 5110(e)(1), or (b) cause this Purchase Warrant or the securities issuable hereunder to be the subject of any
hedging, short sale, derivative, put or call transaction that would result in the effective economic disposition of this Purchase Warrant
or the securities hereunder, except as provided for in FINRA Rule 5110(e)(2). After 180 days after the Effective Date, transfers to others
may be made subject to compliance with or exemptions from applicable securities laws. In order to make any permitted assignment, the
Holder must deliver to the Company the assignment form attached hereto duly executed and completed, together with the Purchase Warrant
and payment of all transfer taxes, if any, payable in connection therewith. The Company shall within five (5) Business Days transfer
this Purchase Warrant on the books of the Company and shall execute and deliver a new Purchase Warrant or Purchase Warrants of like tenor
to the appropriate assignee(s) expressly evidencing the right to purchase the aggregate number of Shares purchasable hereunder or such
portion of such number as shall be contemplated by any such assignment.


 


3.2        Restrictions
Imposed by the Act. The securities evidenced by this Purchase Warrant shall not be transferred unless and until: (i) if required
by applicable law, the Company has received the opinion of counsel for the Company that the securities may be transferred pursuant to
an exemption from registration under the Act and applicable state securities laws, or (ii) a registration statement or a post-effective
amendment to the Registration Statement relating to the offer and sale of such securities has been filed by the Company and declared
effective by the U.S. Securities and Exchange Commission (the ”Commission”) and compliance with applicable state
securities law has been established.


 






    


    


    

 


4.       Piggyback
Registration Rights.


 


4.1       Grant
of Right. Whenever the Company proposes to register any shares of its common stock under the Act (other than (i) a registration effected
solely to implement an employee benefit plan or a transaction to which Rule 145 of the Act is applicable, or (ii) a registration statement
on Form S-4, S-8 or any successor form thereto or another form not available for registering the Shares issuable upon exercise of this
Purchase Warrant for sale to the public, whether for its own account or for the account of one or more stockholders of the Company (a
 “Piggyback Registration”), the Company shall give prompt written notice (in any event no later than ten (10) Business Days
prior to the filing of such registration statement) to the Holder of the Company’s intention to effect such a registration and,
subject to the remaining provisions of this Section 4.1, shall include in such registration such number of Shares underlying this Purchase
Warrant (the “Registrable Securities”) that the Holders have (within ten (10) Business Days of the respective Holder’s
receipt of such notice) requested in writing (including such number) to be included within such registration. If a Piggyback Registration
is an underwritten offering and the managing underwriter advises the Company that it has determined in good faith that marketing factors
require a limit on the number of shares of common stock to be included in such registration, including all Shares issuable upon exercise
of this Purchase Warrant (if the Holder has elected to include such shares in such Piggyback Registration) and all other shares of common
stock proposed to be included in such underwritten offering, , the Company shall include in such registration (i) first, the number of
shares of common stock that the Company proposes to sell and (ii) second, the number of shares of common stock, if any, requested to
be included therein by selling stockholders (including the Holder) allocated pro rata among all such persons on the basis of the number
of shares of common stock then owned by each such person. If any Piggyback Registration is initiated as a primary underwritten offering
on behalf of the Company, the Company shall select the investment banking firm or firms to act as the managing underwriter or underwriters
in connection with such offering. Notwithstanding anything to the contrary, the obligations of the Company pursuant to this Section 4.1
shall terminate on the earlier of (i) the fifth anniversary of the Effective Date and (ii) the date that Rule 144 would allow the Holder
to sell its Registrable Securities during any ninety (90) day period, and shall not be applicable so long as the Company’s Registration
Statement on Form S-1 (No. 333-239676) covering the Registrable Securities remains effective at such time.


 


4.2       Indemnification.
The Company shall indemnify the Holder(s) of the Registrable Securities to be sold pursuant to any registration statement hereunder and
each person, if any, who controls such Holders within the meaning of Section 15 of the Act or Section 20 (a) of the Securities Exchange
Act of 1934, as amended (“Exchange Act”), against all loss, claim, damage, expense or liability (including all reasonable
attorneys’ fees and other out-of-pocket expenses reasonably incurred in investigating, preparing or defending against any claim
whatsoever) to which any of them may become subject under the Act, the Exchange Act or otherwise, arising from such registration statement
but only to the same extent and with the same effect as the provisions pursuant to which the Company has agreed to indemnify the Underwriters
contained in the Underwriting Agreement among the Underwriters and the Company, dated as of [●], 2022. The Holder(s) of the Registrable
Securities to be sold pursuant to such registration statement, and their successors and assigns, shall severally, and not jointly, indemnify
the Company, against all loss, claim, damage, expense or liability (including all reasonable attorneys’ fees and other expenses
reasonably incurred in investigating, preparing or defending against any claim whatsoever) to which they may become subject under the
Act, the Exchange Act or otherwise, arising from information furnished by or on behalf of such Holders, or their successors or assigns,
in writing, for specific inclusion in such registration statement to the same extent and with the same effect as the provisions contained
in the Underwriting Agreement pursuant to which the Underwriters have agreed to indemnify the Company.


 


4.3        Exercise
of Purchase Warrants. Nothing contained in this Purchase Warrant shall be construed as requiring the Holder(s) to exercise their
Purchase Warrants prior to or after the initial filing of any registration statement or the effectiveness thereof.


 


4.4        Reserved.



 


4.5        Underwriting
Agreement. The Holders shall be parties to any underwriting agreement relating to a Piggyback Registration. Such Holders shall not
be required to make any representations or warranties to or agreements with the Company or the underwriters except as they may relate
to such Holders, their Shares and the amount and nature of their ownership thereof and their intended methods of distribution.


 


4.6        Documents
to be Delivered by Holder(s). Each of the Holder(s) participating in any of the foregoing offerings shall furnish to the Company
a completed and executed questionnaire provided by the Company requesting information customarily sought of selling security holders.


 


4.7        Damages.
Should the registration or effectiveness thereof required by Section 4.1 hereof be delayed by the Company, or the Company otherwise fails
to comply with such provisions, the Holder(s) shall, in addition to any other legal or other relief available to the Holder(s), be entitled
to obtain specific performance or other equitable (including injunctive) relief against the threatened breach of such provisions or the
continuation of any such breach, without the necessity of proving actual damages and without the necessity of posting bond or other security.


 






    


    


    

 


4.8       Termination
of Registration Rights. The registration rights afford to Holder(s) under this Section 4 shall terminate on the earliest date when
all Registrable Securities of such Holder either (i) have been sold by such Holder pursuant to a registration statement or (ii) may be
sold by the Holder (including on a cashless basis) within a 90-day period without registration pursuant to Rule 144.


 


5.       New
Purchase Warrants to be Issued.


 


5.1       Partial
Exercise or Transfer. Subject to the restrictions in Section 3 hereof, this Purchase Warrant may be exercised or assigned in whole
or in part. In the event of the exercise or assignment hereof in part only, upon surrender of this Purchase Warrant for cancellation,
together with the duly executed exercise or assignment form and funds sufficient to pay any Exercise Price and/or transfer tax if exercised
pursuant to Section 2.1 hereto, the Company shall cause to be delivered to the Holder without charge a new Purchase Warrant of like tenor
to this Purchase Warrant in the name of the Holder evidencing the right of the Holder to purchase the number of Shares purchasable hereunder
as to which this Purchase Warrant has not been exercised or assigned.


 


5.2        Lost
Certificate. Upon receipt by the Company of evidence satisfactory to it of the loss, theft, destruction or mutilation of this Purchase
Warrant and of reasonably satisfactory indemnification or the posting of a bond, determined in the sole discretion of the Company, the
Company shall execute and deliver a new Purchase Warrant of like tenor and date. Any such new Purchase Warrant executed and delivered
as a result of such loss, theft, mutilation or destruction shall constitute a substitute contractual obligation on the part of the Company.


 


6.       Adjustments.


 


6.1       Adjustments
to Exercise Price and Number of Securities. The Exercise Price and the number of Shares underlying the Purchase Warrant shall be
subject to adjustment from time to time as hereinafter set forth:


 


6.1.1       Share
Dividends; Split Ups. If, after the date hereof, and subject to the provisions of Section 6.3 below, the number of outstanding
Shares is increased by a stock dividend payable in Shares or by a split up of Shares or other similar event, then, on the effective day
thereof, the number of Shares purchasable hereunder shall be increased in proportion to such increase in outstanding Shares, and the
Exercise Price shall be proportionately decreased.


 


6.1.2        Aggregation
of Shares. If, after the date hereof, and subject to the provisions of Section 6.3 below, the number of outstanding Shares is decreased
by a consolidation, combination or reclassification of Shares or other similar event, then, on the effective date thereof, the number
of Shares purchasable hereunder shall be decreased in proportion to such decrease in outstanding Shares, and the Exercise Price shall
be proportionately increased.


 


6.1.3        Replacement
of Securities upon Reorganization, etc. In case of any reclassification or reorganization of the outstanding Shares other than
a change covered by Section 6.1.1 or 6.1.2 hereof or that solely affects the par value of such Shares, or in the case of any share reconstruction
or amalgamation or consolidation or merger of the Company with or into another corporation (other than a consolidation or share reconstruction
or amalgamation or merger in which the Company is the continuing corporation and that does not result in any reclassification or reorganization
of the outstanding Shares), or in the case of any sale or conveyance to another corporation or entity of the property of the Company
as an entirety or substantially as an entirety in connection with which the Company is dissolved, the Holder of this Purchase Warrant
shall have the right thereafter (until the expiration of the right of exercise of this Purchase Warrant) to receive upon the exercise
hereof, for the same aggregate Exercise Price payable hereunder immediately prior to such event, the kind and amount of shares of stock
or other securities or property (including cash) receivable upon such reclassification, reorganization, share reconstruction or amalgamation,
or consolidation, or upon a dissolution following any such sale or transfer, by a Holder of the number of Shares of the Company obtainable
upon exercise of this Purchase Warrant immediately prior to such event; and if any reclassification also results in a change in Shares
covered by Section 6.1.1 or 6.1.2, then such adjustment shall be made pursuant to Sections 6.1.1, 6.1.2 and this Section 6.1.3. The provisions
of this Section 6.1.3 shall similarly apply to successive reclassifications, reorganizations, share reconstructions or amalgamations,
or consolidations, sales or other transfers.


 






    


    


    

 


6.1.4        Changes
in Form of Purchase Warrant. This form of Purchase Warrant need not be changed because of any change pursuant to this Section
6.1, and Purchase Warrants issued after such change may state the same Exercise Price and the same number of Shares as are stated in
the Purchase Warrants initially issued pursuant to this Agreement. The acceptance by any Holder of the issuance of new Purchase Warrants
reflecting a required or permissive change shall not be deemed to waive any rights to an adjustment occurring after the Commencement
Date or the computation thereof.


 


6.2        Substitute
Purchase Warrant. In case of any consolidation of the Company with, or share reconstruction or amalgamation or merger of the Company
with or into, another corporation (other than a consolidation or share reconstruction or amalgamation or merger which does not result
in any reclassification or change of the outstanding Shares), the corporation formed by such consolidation or share reconstruction or
amalgamation shall execute and deliver to the Holder a supplemental Purchase Warrant providing that the holder of each Purchase Warrant
then outstanding or to be outstanding shall have the right thereafter (until the stated expiration of such Purchase Warrant) to receive,
upon exercise of such Purchase Warrant, the kind and amount of shares of stock and other securities and property receivable upon such
consolidation or share reconstruction or amalgamation, by a holder of the number of Shares of the Company for which such Purchase Warrant
might have been exercised immediately prior to such consolidation, share reconstruction or amalgamation or merger, sale or transfer.
Such supplemental Purchase Warrant shall provide for adjustments which shall be identical to the adjustments provided for in this Section
6. The above provision of this Section shall similarly apply to successive consolidations or share reconstructions or amalgamations or
mergers.


 


6.3        Elimination
of Fractional Interests. The Company shall not be required to issue certificates representing fractions of Shares upon the exercise
of the Purchase Warrant, nor shall it be required to issue scrip or pay cash in lieu of any fractional interests, it being the intent
of the parties that all fractional interests shall be eliminated by rounding any fraction up or down, as the case may be, to the nearest
whole number of Shares or other securities, properties or rights.


 


7.       Reservation.
The Company shall at all times reserve and keep available out of its authorized Shares, solely for the purpose of issuance upon exercise
of the Purchase Warrants, such number of Shares or other securities, properties or rights as shall be issuable upon the exercise thereof.
The Company covenants and agrees that, upon exercise of the Purchase Warrants and payment of the Exercise Price therefor, in accordance
with the terms hereby, all Shares and other securities issuable upon such exercise shall be duly and validly issued, fully paid and non-assessable
and not subject to preemptive rights of any shareholder.


 


8.       Certain
Notice Requirements.


 


8.1       Holder’s
Right to Receive Notice. Nothing herein shall be construed as conferring upon the Holders the right to vote or consent or to receive
notice as a shareholder for the election of directors or any other matter, or as having any rights whatsoever as a shareholder of the
Company. If, however, at any time prior to the expiration of the Purchase Warrants and their exercise, any of the events described in
Section 8.2 shall occur, then, in one or more of said events, the Company shall deliver to each Holder a copy of each notice relating
to such events given to the other shareholders of the Company at the same time and in the same manner that such notice is given to the
shareholders.


 


8.2        Events
Requiring Notice. The Company shall be required to give the notice described in this Section 8 upon one or more of the following
events: (i) if the Company shall take a record of the holders of its Shares for the purpose of entitling them to receive a dividend or
distribution payable otherwise than in cash, or a cash dividend or distribution payable otherwise than out of retained earnings, as indicated
by the accounting treatment of such dividend or distribution on the books of the Company, or (ii) the Company shall offer to all the
holders of its Shares any additional shares of capital stock of the Company or securities convertible into or exchangeable for shares
of capital stock of the Company, or any option, right or warrant to subscribe therefor.


 


8.3        Notice
of Change in Exercise Price. The Company shall, promptly after an event requiring a change in the Exercise Price pursuant to Section
6 hereof, send notice to the Holders of such event and change (“Price Notice”). The Price Notice shall describe the
event causing the change and the method of calculating same.


 






    


    


    

 


8.4        Transmittal
of Notices. All notices, requests, consents and other communications under this Purchase Warrant shall be in writing and shall be
deemed to have been duly made when hand delivered, or mailed by express mail or private courier service: (i) if to the registered Holder
of the Purchase Warrant, to the address of such Holder as shown on the books of the Company, or (ii) if to the Company, to following
address or to such other address as the Company may designate by notice to the Holders:


 


If to the Holder:


 


[●]


Attention: [●]


 


with a copy (which shall not constitute notice) to:




Brunson Chandler & Jones, PLLC


Walker Center, 14th Floor


175 S. Main St., Suite 1410


Salt Lake City, UT 84111


Attention: Lance Brunson


 


If to the Company:


 


PaxMedica, Inc.


303 South Broadway, Suite 125


Tarrytown, NY 10591


Attention: Howard Weisman


 


with a copy (which shall not constitute notice)
to:




Dechert LLP


1095 Avenue of the Americas


New York, NY 10036


Attention: David S. Rosenthal; Anna Tomczyk


 


9.       Miscellaneous.


 


9.1       Amendments.
The Company and [●] may from time to time supplement or amend this Purchase Warrant without the approval of any of the Holders
in order to cure any ambiguity, to correct or supplement any provision contained herein that may be defective or inconsistent with any
other provisions herein, or to make any other provisions in regard to matters or questions arising hereunder that the Company and [●]
may deem necessary or desirable and that the Company and [●] deem shall not adversely affect the interest of the Holders. All other
modifications or amendments shall require the written consent of and be signed by (i) the Company and (ii) the Holder(s) of Purchase
Warrants then-exercisable for at least a majority of the Shares then-exercisable pursuant to all then-outstanding Purchase Warrants.


 


9.2        Headings.
The headings contained herein are for the sole purpose of convenience of reference, and shall not in any way limit or affect the meaning
or interpretation of any of the terms or provisions of this Purchase Warrant.


 


9.3.        Entire
Agreement. This Purchase Warrant (together with the other agreements and documents being delivered pursuant to or in connection with
this Purchase Warrant) constitutes the entire agreement of the parties hereto with respect to the subject matter hereof, and supersedes
all prior agreements and understandings of the parties, oral and written, with respect to the subject matter hereof.


 


9.4        Binding
Effect. This Purchase Warrant shall inure solely to the benefit of and shall be binding upon, the Holder and the Company and their
permitted assignees, respective successors, legal representative and assigns, and no other person shall have or be construed to have
any legal or equitable right, remedy or claim under or in respect of or by virtue of this Purchase Warrant or any provisions herein contained.


 






    


    


    

 


9.5        Governing
Law; Submission to Jurisdiction; Trial by Jury. This Purchase Warrant shall be governed by and construed and enforced in accordance
with the laws of the State of New York, without giving effect to conflict of laws principles thereof. The Company hereby agrees that
any action, proceeding or claim against it arising out of, or relating in any way to this Purchase Warrant shall be brought and enforced
in the courts located in New York, New York, or in the United States District Court located in New York, 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 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 8 hereof. Such mailing shall be deemed personal service and shall be legal and binding upon the Company in any action, proceeding
or claim. The Company and the Holder agree that the prevailing party(ies) in any such action shall be entitled to recover from the other
party(ies) all of its reasonable attorneys’ fees and expenses relating to such action or proceeding and/or incurred in connection
with the preparation therefor. The Company (on its behalf and, to the extent permitted by applicable law, on behalf of its stockholders
and affiliates) and the Holder hereby irrevocably waive, to the fullest extent permitted by applicable law, any and all right to trial
by jury in any legal proceeding arising out of or relating to this Agreement or the transactions contemplated hereby.


 


9.6        Waiver,
etc. The failure of the Company or the Holder to at any time enforce any of the provisions of this Purchase Warrant shall not be
deemed or construed to be a waiver of any such provision, nor to in any way affect the validity of this Purchase Warrant or any provision
hereof or the right of the Company or any Holder to thereafter enforce each and every provision of this Purchase Warrant. No waiver of
any breach, non-compliance or non-fulfillment of any of the provisions of this Purchase Warrant shall be effective unless set forth in
a written instrument executed by the party or parties against whom or which enforcement of such waiver is sought; and no waiver of any
such breach, non-compliance or non-fulfillment shall be construed or deemed to be a waiver of any other or subsequent breach, non-compliance
or non-fulfillment.


 


9.7        Exchange
Agreement. As a condition of the Holder’s receipt and acceptance of this Purchase Warrant, Holder agrees that, at any time
prior to the complete exercise of this Purchase Warrant by Holder, if the Company and [●] enter into an agreement (“Exchange
Agreement”) pursuant to which they agree that all outstanding Purchase Warrants will be exchanged for securities or cash or
a combination of both, then Holder shall agree to such exchange and become a party to the Exchange Agreement.


 


[Signature Page Follows]


 






    


    


    

 


IN WITNESS WHEREOF, the Company has caused this
Purchase Warrant to be signed by its duly authorized officer as of the [●] day of [●], 202_.


 


		PaxMedica, Inc.	



 


	 	By:	 	 






	 	Name:	 	 
	 	Title:	 	 



 








 






    


    


    

 


[Form to be used to exercise Purchase Warrant]


 


Date: __________, 20___


 


The undersigned
hereby elects irrevocably to exercise the Purchase Warrant for ______ shares of common stock, par value $0.0001 per share (the “Shares”),
of PaxMedica, Inc., a Delaware corporation (the “Company”), and hereby makes payment of $____ (at the rate of $____
per Share) in payment of the Exercise Price pursuant thereto. Please issue the Shares as to which this Purchase Warrant is exercised
in accordance with the instructions given below and, if applicable, a new Purchase Warrant representing the number of Shares for which
this Purchase Warrant has not been exercised.


 


or


 


The undersigned
hereby elects irrevocably to convert its right to purchase ___ Shares of the Company under the Purchase Warrant for ______ Shares, as
determined in accordance with the following formula:


 


	 	X	=	Y(A-B)	 
	A	 



 


	Where,	 	 	 
	 	X	=	The
    number of Shares to be issued to Holder;
	 	Y	=	The
    number of Shares for which the Purchase Warrant is being exercised;
	 	A	=	The
    fair market value of one Share which is equal to $_____; and
	 	B	=	The
    Exercise Price which is equal to $______ per share



 


The undersigned
agrees and acknowledges that the calculation set forth above is subject to confirmation by the Company and any disagreement with respect
to the calculation shall be resolved by the Company in its sole discretion.


 


Please issue the
Shares as to which this Purchase Warrant is exercised in accordance with the instructions given below and, if applicable, a new Purchase
Warrant representing the number of Shares for which this Purchase Warrant has not been converted.


 


 


Signature _____________________________________________


  


 


Signature Guaranteed ____________________________________


 


 


INSTRUCTIONS FOR REGISTRATION OF SECURITIES


 


	Name:	 	 
	 	(Print in Block Letters)	 
	 	 	 
	Address:	 	 
	 	 	 
	 	 	 
	 	 	 


NOTICE: The signature to this form must correspond
with the name as written upon the face of the Purchase Warrant without alteration or enlargement or any change whatsoever, and must be
guaranteed by a bank, other than a savings bank, or by a trust company or by a firm having membership on a registered national securities
exchange.


 






    


    


    

 


[Form to be used to assign Purchase Warrant]


ASSIGNMENT


 


(To be executed by the registered Holder to effect
a transfer of the within Purchase Warrant):


 


FOR VALUE RECEIVED, __________________ does hereby
sell, assign and transfer unto the right to purchase shares of common stock, par value $0.0001 per share, of PaxMedica, Inc., a Delaware
corporation (the “Company”), evidenced by the Purchase Warrant and does hereby authorize the Company to transfer such
right on the books of the Company.


 


Dated: __________, 20__


 


Signature ____________________________________________


 


Signature Guaranteed ___________________________________


 


NOTICE: The signature to this form must correspond with the name as
written upon the face of the within Purchase Warrant without alteration or enlargement or any change whatsoever, and must be guaranteed
by a bank, other than a savings bank, or by a trust company or by a firm having membership on a registered national securities exchange.