Exhibit
4.1


 




 


Hemispherx
Biopharma, Inc.


 


and


 


American
Stock Transfer & Trust Company, LLC, as


Warrant
Agent


 


 




Warrant
Agency Agreement


 


Dated
as of March 8, 2019


 




    	 	 	 



    	 



    

 


WARRANT
AGENCY AGREEMENT


 


WARRANT
AGENCY AGREEMENT, dated as of March 8, 2019 (“Agreement”), between Hemispherx Biopharma, Inc., a Delaware
corporation (the “Company”), and American Stock Transfer & Trust Company, LLC, a New York limited liability
company (the “Warrant Agent”).


 


W
I T N E S S E T H


 


WHEREAS,
the Company is engaged in a public rights offering (the “Offering”) pursuant to which the Company has distributed,
at no charge, non-transferable subscription rights to purchase units (the “Units”) to each of the Company’s
holders of common stock (the “Common Stock”) and to certain of the Company’s warrant and option holders
pursuant to an effective registration statement on Form S-1 (File No. 333-229051) (the “Registration Statement”);


 


WHEREAS,
the Units consists of shares of Series B Convertible Preferred Stock (the “Preferred Stock”) and warrants (collectively,
the “Warrants”) to purchase shares of Common Stock, and the Company wishes to issue the Warrants in book entry
form entitling the respective holders of the Warrants (the “Holders”, which term shall include a Holder’s
transferees, successors and assigns and “Holder” shall include, if the Warrants are held in “street name,”
a Participant (as defined below) or a designee appointed by such Participant) to purchase an aggregate of up to 40,000,000 shares
of Common Stock upon the terms and subject to the conditions hereinafter set forth;


 


WHEREAS,
the Preferred Stock and Warrants to be issued in connection with the Offering shall be immediately separable and will be issued
separately, but will be purchased together in the Offering; and


 


WHEREAS,
the Company wishes the Warrant Agent to act on behalf of the Company, and the Warrant Agent is willing so to act, in connection
with the issuance, registration, transfer, exchange, exercise and replacement of the Warrants and, in the Warrant Agent’s
capacity as the Company’s transfer agent, the delivery of the Warrant Shares (as defined below).


 


NOW,
THEREFORE, in consideration of the premises and the mutual agreements herein set forth, the parties hereby agree as follows:


 


Section
1. Certain Definitions. For purposes of this Agreement, the following terms have the meanings indicated:


 


(a)
“Business Day” means any day except any Saturday, any Sunday, any day which is a federal legal holiday in the
United States or any day on which the New York Stock Exchange is authorized or required by law or other governmental action to
close.


 


(b)
“Close of Business” on any given date means 5:00 p.m., New York City time, on such date; provided, however,
that if such date is not a Business Day it means 5:00 p.m., New York City time, on the next succeeding Business Day.


 


(c)
“Person” means an individual, corporation, association, partnership, limited liability company, joint venture,
trust, unincorporated organization, government or political subdivision thereof or governmental agency or other entity.


 


(d)
“Warrant Certificate” means a certificate issued to a Holder, representing such number of Warrant Shares as
is indicated therein.


 


(e)
“Warrant Shares” means the shares of Common Stock underlying the Warrants and issuable upon exercise of the
Warrants.


 


All
other capitalized terms used but not otherwise defined herein shall have the meaning ascribed to such terms in the Warrant.


 


Section
2. Appointment of Warrant Agent. The Company hereby appoints the Warrant Agent to act as agent for the Company in accordance
with the terms and conditions hereof, and the Warrant Agent hereby accepts such appointment. The Company may from time to time
appoint a Co-Warrant Agent as it may, in its sole discretion, deem necessary or desirable. The Warrant Agent shall have no duty
to supervise, and will in no event be liable for the acts or omissions of, any co-Warrant Agent.


 




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Section
3. Global Warrants.


 


(a)
The Warrants shall be issuable in book entry form (the “Global Warrants”). All of the Warrants shall initially
be represented by one or more Global Warrants deposited with the Warrant Agent and registered in the name of Cede & Co., a
nominee of The Depository Trust Company (the “Depositary”), or as otherwise directed by the Depositary. Ownership
of beneficial interests in the Warrants shall be shown on, and the transfer of such ownership shall be effected through, records
maintained by (i) the Depositary or its nominee for each Global Warrant or (ii) institutions that have accounts with the Depositary
(such institution, with respect to a Warrant in its account, a “Participant”).


 


(b)
If the Depositary subsequently ceases to make its book-entry settlement system available for the Warrants, the Company may instruct
the Warrant Agent regarding other arrangements for book-entry settlement. In the event that the Warrants are not eligible for,
or it is no longer necessary to have the Warrants available in, book-entry form, the Warrant Agent shall provide written instructions
to the Depositary to deliver to the Warrant Agent for cancellation each Global Warrant, and the Company shall instruct the Warrant
Agent to deliver to each Holder a Warrant Certificate.


 


(c)
A Holder has the right to elect at any time or from time to time a Warrant Exchange (as defined below) pursuant to a Warrant Certificate
Request Notice (as defined below). Upon written notice by a Holder to the Warrant Agent for the exchange of some or all of such
Holder’s Global Warrants for a Warrant Certificate evidencing the same number of Warrants, which request shall be in the
form attached hereto as Annex A (a “Warrant Certificate Request Notice” and the date of delivery of
such Warrant Certificate Request Notice by the Holder, the “Warrant Certificate Request Notice Date” and the
deemed surrender upon delivery by the Holder of a number of Global Warrants for the same number of Warrants evidenced by a Warrant
Certificate, a “Warrant Exchange”), the Warrant Agent shall promptly effect the Warrant Exchange and shall
promptly issue and deliver to the Holder a Warrant Certificate for such number of Warrants in the name set forth in the Warrant
Certificate Request Notice. Such Warrant Certificate shall be dated the original issue date of the Warrants and shall be executed
by an authorized signatory of the Company. In connection with a Warrant Exchange, the Company agrees to deliver, or to direct
the Warrant Agent to deliver, the Warrant Certificate to the Holder within two (2) Business Days of the Warrant Certificate Request
Notice pursuant to the delivery instructions in the Warrant Certificate Request Notice (“Warrant Certificate Delivery
Date”). If the Company fails for any reason to deliver to the Holder the Warrant Certificate subject to the Warrant
Certificate Request Notice by the Warrant Certificate Delivery Date, the Company shall pay to the Holder, in cash, as liquidated
damages and not as a penalty, for each $1,000 of Warrant Shares evidenced by such Warrant Certificate (based on the VWAP (as defined
in the Warrant) of the Common Stock on the Warrant Certificate Request Notice Date), $10 per Business Day (increasing to $20 per
Business Day on the fifth Business Day after such liquidated damages begin to accrue) for each Business Day after such Warrant
Certificate Delivery Date until such Warrant Certificate is delivered or, prior to delivery of such Warrant Certificate, the Holder
rescinds such Warrant Exchange. The Company covenants and agrees that, upon the date of delivery of the Warrant Certificate Request
Notice, the Holder shall be deemed to be the holder of the Warrant Certificate and, notwithstanding anything to the contrary set
forth herein, the Warrant Certificate shall be deemed for all purposes to contain all of the terms and conditions of the Warrants
evidenced by such Warrant Certificate and the terms of this Agreement, other than Section 3(c), which shall not apply to the Warrants
evidenced by a Warrant Certificate. In the event a beneficial owner requests a Warrant Exchange, upon issuance of the paper Warrant
Certificate, the Company shall act as warrant agent and the terms of the paper Warrant Certificate so issued shall exclusively
govern in respect thereof.


 


Section
4. Form of Warrant. The Warrants, together with the form of election to purchase Common Stock (the “Exercise Notice”)
and the form of assignment to be printed on the reverse thereof, whether a Warrant Certificate or a Global Warrant, shall be substantially
in the form of Exhibit 1 hereto.


 


Section
5. Countersignature and Registration. The Warrants shall be executed on behalf of the Company by its Chief Executive Officer
or Chief Financial Officer, either manually or by facsimile signature, and have affixed thereto the Company’s seal or a
facsimile thereof which shall be attested by the Secretary or an Assistant Secretary of the Company, either manually or by facsimile
signature. The Warrants shall be countersigned by the Warrant Agent either manually or by facsimile signature and shall not be
valid for any purpose unless so countersigned. In case any officer of the Company who shall have signed a Warrant shall cease
to be such officer of the Company before countersignature by the Warrant Agent and issuance and delivery by the Company, such
Warrant, nevertheless, may be countersigned by the Warrant Agent, issued and delivered with the same force and effect as though
the person who signed such Warrant had not ceased to be such officer of the Company; and any Warrant may be signed on behalf of
the Company by any person who, at the actual date of the execution of such Warrant, shall be a proper officer of the Company to
sign such Warrant, although at the date of the execution of this Warrant Agreement any such person was not such an officer.


 




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The
Warrant Agent will keep or cause to be kept, at one of its offices, or at the office of one of its agents, books for registration
and transfer of the Warrant Certificates issued hereunder. Such books shall show the names and addresses of the respective registered
Holders of the Warrant Certificates, the number of warrants evidenced on the face of each of such Warrant Certificate and the
date of each of such Warrant Certificate. The Warrant Agent will create a special account for the issuance of Warrant Certificates.


 


Section
6. Transfer, Split Up, Combination and Exchange of Warrant Certificates; Mutilated, Destroyed, Lost or Stolen Warrant Certificates.
Subject to the provisions of the Warrant and the last sentence of this first paragraph of Section 6 and subject to applicable
law, rules or regulations, or any “stop transfer” instructions the Company may give to the Warrant Agent, at any time
after the closing date of the Offering, and at or prior to the Close of Business on the Termination Date, any Warrant Certificate
or Warrant Certificates or Global Warrant or Global Warrants may be transferred, split up, combined or exchanged for another Warrant
Certificate or Warrant Certificates or Global Warrant or Global Warrants, entitling the Holder to purchase a like number of shares
of Common Stock as the Warrant Certificate or Warrant Certificates or Global Warrant or Global Warrants surrendered then entitled
such Holder to purchase. Any Holder desiring to transfer, split up, combine or exchange any Warrant Certificate or Global Warrant
shall make such request in writing delivered to the Warrant Agent, and shall surrender the Warrant Certificate or Warrant Certificates
to be transferred, split up, combined or exchanged at the principal office of the Warrant Agent, provided that no such surrender
is applicable to the Holder of a Global Warrant. Any requested transfer of Warrants, whether a Global Warrant or a Warrant Certificate,
shall be accompanied by reasonable evidence of authority of the party making such request that may be required by the Warrant
Agent. Thereupon the Warrant Agent shall, subject to the last sentence of this first paragraph of Section 6, countersign and deliver
to the Person entitled thereto any Warrant Certificate or Global Warrant, as the case may be, as so requested. The Company may
require payment from the Holder of a sum sufficient to cover any tax or governmental charge that may be imposed in connection
with any transfer, split up, combination or exchange of Warrants. The Company shall compensate the Warrant Agent per the fee schedule
mutually agreed upon by the parties hereto and provided separately on the date hereof.


 


Upon
receipt by the Warrant Agent of evidence reasonably satisfactory to it of the loss, theft, destruction or mutilation of a Warrant
Certificate, which evidence shall include an affidavit of loss, or in the case of mutilated certificates, the certificate or portion
thereof remaining, and, in case of loss, theft or destruction, of indemnity in customary form and amount, and satisfaction of
any other reasonable requirements established by Section 8-405 of the Uniform Commercial Code as in effect in the State of Delaware,
and reimbursement to the Company and the Warrant Agent of all reasonable expenses incidental thereto, and upon surrender to the
Warrant Agent and cancellation of the Warrant Certificate if mutilated, the Company will make and deliver a new Warrant Certificate
of like tenor to the Warrant Agent for delivery to the Holder in lieu of the Warrant Certificate so lost, stolen, destroyed or
mutilated.


 


Section
7. Exercise of Warrants; Exercise Price; Termination Date.


 


(a)
The Warrants shall be exercisable commencing on the Initial Exercise Date. The Warrants shall cease to be exercisable and shall
terminate and become void, and all rights thereunder and under this Agreement shall cease, at or prior to the Close of Business
on the Termination Date. Subject to the foregoing and to Section 7(b) below, the Holder of a Warrant may exercise the Warrant
in whole or in part upon providing the items required by Section 7(c) below to the Warrant Agent at the principal office of the
Warrant Agent or to the office of one of its agents as may be designated by the Warrant Agent from time to time. In the case of
the Holder of a Global Warrant, the Holder shall deliver the executed Exercise Notice and payment of the Exercise Price pursuant
to Section 2(a) of the Warrant. Notwithstanding any other provision in this Agreement, a holder whose interest in a Global Warrant
is a beneficial interest in a Global Warrant held in book-entry form through the Depositary (or another established clearing corporation
performing similar functions), shall effect exercises by delivering to the Depositary (or such other clearing corporation, as
applicable) the appropriate instruction form for exercise, complying with the procedures to effect exercise that are required
by the Depositary (or such other clearing corporation, as applicable). The Company acknowledges that the bank accounts maintained
by the Warrant Agent in connection with the services provided under this Agreement will be in its name and that the Warrant Agent
may receive investment earnings in connection with the investment at Warrant Agent risk and for its benefit of funds held in those
accounts from time to time. Neither the Company nor the Holders will receive interest on any deposits or Exercise Price.


 


(b)
Upon receipt of an Exercise Notice for a cashless exercise pursuant to Section 2(c) of the Warrant (each, a “Cashless
Exercise”), the Company will promptly calculate and transmit to the Warrant Agent the number of Warrant Shares issuable
in connection with such Cashless Exercise and deliver a copy of the Exercise Notice to the Warrant Agent, which shall issue such
number of Warrant Shares in connection with such Cashless Exercise.


 




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(c)
Upon the Warrant Agent’s receipt, at or prior to the Close of Business on the Termination Date set forth in a Warrant, of
the executed Exercise Notice, accompanied by payment of the Exercise Price pursuant to Section 2(a) of the Warrant, the shares
to be purchased (other than in the case of a Cashless Exercise), an amount equal to any applicable tax, governmental charge or
expense reimbursement referred to in Section 6 by wire transfer, in cash, or by certified check or bank draft payable to the order
of the Company and, in the case of an exercise of a Warrant in the form of a Warrant Certificate for all of the Warrant Shares
represented thereby, the Warrant Certificate, the Warrant Agent shall cause the Warrant Shares underlying such Warrant to be delivered
to or upon the order of the Holder of such Warrant, registered in such name or names as may be designated by such Holder, no later
than the Warrant Share Delivery Date. If the Company is then a participant in the DWAC system of the Depositary and either (A)
there is an effective registration statement permitting the issuance of the Warrant Shares to or resale of the Warrant Shares
by Holder or (B) the Warrant is being exercised via Cashless Exercise, then the certificates for Warrant Shares shall be transmitted
by the Warrant Agent to the Holder by crediting the account of the Holder’s broker with the Depositary through its DWAC
system, provided the Holder’s broker has properly initiated said DWAC. For the avoidance of doubt, if the Company becomes
obligated to pay any amounts to any Holders pursuant to Section 2(d)(i) or 2(d)(iv) of the Warrant, such obligation shall be solely
that of the Company and not that of the Warrant Agent. Notwithstanding anything else to the contrary in this Agreement, except
in the case of a Cashless Exercise, if any Holder fails to duly deliver payment to the Warrant Agent of an amount equal to the
aggregate Exercise Price of the Warrant Shares to be purchased upon exercise of such Holder’s Warrant as set forth in Section
7(a) hereof, the Warrant Agent will not obligated to deliver certificates representing any such Warrant Shares (via DWAC or otherwise)
until following receipt of such payment, and the applicable Warrant Share Delivery Date shall be deemed extended by one day for
each day (or part thereof) until such payment is delivered to the Warrant Agent.


 


(d)
The Warrant Agent shall deposit all funds received by it in payment of the Exercise Price for all Warrants in the account of the
Company maintained with the Warrant Agent for such purpose (or to such other account as directed by the Company in writing) and
shall advise the Company via telephone at the end of each day on which funds for the exercise of any Warrant are received of the
amount so deposited to its account. The Warrant Agent shall promptly confirm such telephonic advice to the Company in writing.


 


(e)
In case the Holder of any Warrant Certificate exercises fewer than all Warrants evidenced thereby and surrenders such Warrant
Certificate in connection with such partial exercise, a new Warrant Certificate evidencing the number of Warrant Shares equivalent
to the number of Warrant Shares remaining unexercised may be issued by the Warrant Agent to the Holder of such Warrant Certificate
or to his duly authorized assigns in accordance with Section 2(d)(ii) of the Warrant, subject to the provisions of Section 6 hereof.


 


Section
8. Cancellation and Destruction of Warrant Certificates. All Warrant Certificates surrendered for the purpose of exercise,
transfer, split up, combination or exchange shall, if surrendered to the Company or to any of its agents, be delivered to the
Warrant Agent for cancellation or in canceled form, or, if surrendered to the Warrant Agent, shall be canceled by it, and no Warrant
Certificates shall be issued in lieu thereof except as expressly permitted by any of the provisions of this Agreement. The Company
shall deliver to the Warrant Agent for cancellation and retirement, and the Warrant Agent shall so cancel and retire, any other
Warrant Certificate purchased or acquired by the Company otherwise than upon the exercise thereof. The Warrant Agent shall deliver
all canceled Warrant Certificates to the Company, or shall, at the written request of the Company, destroy such canceled Warrant
Certificates, and in such case shall deliver a certificate of destruction thereof to the Company, subject to any applicable law,
rule or regulation requiring the Warrant Agent to retain such canceled certificates.


 


Section
9. Certain Representations; Reservation and Availability of Shares of Common Stock or Cash.


 


(a)
This Agreement has been duly authorized, executed and delivered by the Company and, assuming due authorization, execution and
delivery hereof by the Warrant Agent, constitutes a valid and legally binding obligation of the Company enforceable against the
Company in accordance with its terms, and the Warrants have been duly authorized, executed and issued by the Company and, assuming
due authentication thereof by the Warrant Agent pursuant hereto and payment therefor by the Holders as provided in the Registration
Statement, constitute valid and legally binding obligations of the Company enforceable against the Company in accordance with
their terms and entitled to the benefits thereof; in each case except as enforceability may be limited by bankruptcy, insolvency,
reorganization, moratorium and other similar laws relating to or affecting creditors’ rights generally or by general equitable
principles (regardless of whether such enforceability is considered in a proceeding in equity or at law).


 




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(b)
As of the date hereof and prior to the Offering, the authorized capital stock of the Company consists of (i) 350,000,000 shares
of Common Stock, of which 48,935,318 shares of Common Stock are issued and outstanding, and (ii) 5,000,000 shares of preferred
stock, par value $0.01 per share, of which 250,000 are designated Series A Junior Participating Preferred Stock, of which none
are issued and outstanding, and 10,000 are designated Series B Convertible Preferred Stock, of which none are issued and outstanding.
40,000,000 shares of Common Stock are reserved for issuance upon exercise of the Warrants. Except as disclosed in the Registration
Statement, there are no other outstanding obligations, warrants, options or other rights to subscribe for or purchase from the
Company any class of capital stock of the Company.


 


(c)
The Company covenants and agrees that it will cause to be reserved and kept available out of its authorized and unissued shares
of Common Stock or its authorized and issued shares of Common Stock held in its treasury, free from preemptive rights, the number
of shares of Common Stock that will be sufficient to permit the exercise in full of all outstanding Warrants.


 


(d)
The Warrant Agent will create a special account for the issuance of Common Stock upon the exercise of Warrants.


 


(e)
The Company further covenants and agrees that it will pay when due and payable any and all federal and state transfer taxes and
charges which may be payable in respect of the original issuance or delivery of the Warrant Certificates or certificates evidencing
Common Stock upon exercise of the Warrants. The Company shall not, however, be required to pay any tax or governmental charge
which may be payable in respect of any transfer involved in the transfer or delivery of Warrant Certificates or the issuance or
delivery of certificates for Common Stock in a name other than that of the Holder of the Warrant Certificate evidencing Warrants
surrendered for exercise or to issue or deliver any certificate for shares of Common Stock upon the exercise of any Warrants until
any such tax or governmental charge shall have been paid (any such tax or governmental charge being payable by the Holder of such
Warrant Certificate at the time of surrender) or until it has been established to the Company’s reasonable satisfaction
that no such tax or governmental charge is due.


 


Section
10. Common Stock Record Date. Each Holder shall be deemed to have become the holder of record for the Warrant Shares pursuant
to Section 2(d)(i) of the Warrants.


 


Section
11. Adjustment of Exercise Price, Number of Shares of Common Stock or Number of the Company Warrants. The Exercise Price,
the number of shares covered by each Warrant and the number of Warrants outstanding are subject to adjustment from time to time
as provided in Section 3 of the Warrant. In the event that at any time, as a result of an adjustment made pursuant to Section
3 of the Warrant, the Holder of any Warrant thereafter exercised shall become entitled to receive any shares of capital stock
of the Company other than shares of Common Stock, thereafter the number of such other shares so receivable upon exercise of any
Warrant shall be subject to adjustment from time to time in a manner and on terms as nearly equivalent as practicable to the provisions
with respect to the shares contained in Section 3 of the Warrant, and the provisions of Sections 7, 9 and 13 of this Agreement
with respect to the shares of Common Stock shall apply on like terms to any such other shares. All Warrants originally issued
by the Company subsequent to any adjustment made to the Exercise Price pursuant to the Warrant shall evidence the right to purchase,
at the adjusted Exercise Price, the number of shares of Common Stock purchasable from time to time hereunder upon exercise of
the Warrants, all subject to further adjustment as provided herein.


 


Section
12. Certification of Adjusted Exercise Price or Number of Shares of Common Stock. Whenever the Exercise Price or the number
of shares of Common Stock issuable upon the exercise of each Warrant is adjusted as provided in Section 11 or 13, the Company
shall (a) promptly prepare a certificate setting forth the Exercise Price of each Warrant as so adjusted, and a brief statement
of the facts accounting for such adjustment, (b) promptly file with the Warrant Agent and with each transfer agent for the Common
Stock a copy of such certificate and (c) instruct the Warrant Agent to send a brief summary thereof to each Holder of a Warrant.


 


Section
13. Fractional Shares of Common Stock.


 


(a)
The Company shall not issue fractions of Warrants or distribute a Global Warrant or Warrant Certificates that evidence fractional
Warrants. Whenever any fractional Warrant would otherwise be required to be issued or distributed, the actual issuance or distribution
shall reflect a rounding of such fraction either up or down to the nearest whole Warrant.


 




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(b)
The Company shall not issue fractions of shares of Common Stock upon exercise of Warrants or distribute stock certificates that
evidence fractional shares of Common Stock. Whenever any fraction of a share of Common Stock would otherwise be required to be
issued or distributed, the actual issuance or distribution in respect thereof shall be made in accordance with Section 2(d)(v)
of the Warrant.


 


Section
14. Conditions of the Warrant Agent’s Obligations. The Warrant Agent accepts its obligations herein set forth upon
the terms and conditions hereof, including the following to all of which the Company agrees and to all of which the rights hereunder
of the Holders from time to time of the Warrant shall be subject:


 


(a)
Compensation and Indemnification. The Company agrees promptly to pay the Warrant Agent the compensation detailed on Exhibit 2
hereto for all services rendered by the Warrant Agent and to reimburse the Warrant Agent for reasonable out-of-pocket expenses
(including reasonable counsel fees) incurred without gross negligence, bad faith or willful misconduct by the Warrant Agent in
connection with the services rendered hereunder by the Warrant Agent. The Company also agrees to indemnify the Warrant Agent for,
and to hold it harmless against, any loss, liability or expense incurred without gross negligence, bad faith or willful misconduct
on the part of the Warrant Agent, arising out of or in connection with its acting as Warrant Agent hereunder, including the reasonable
costs and expenses of defending against any claim of such liability.


 


(b)
Agent for the Company. In acting under this Warrant Agreement and in connection with the Warrant Certificates, the Warrant Agent
is acting solely as agent of the Company and does not assume any obligations or relationship of agency or trust for or with any
of the Holders of Warrant Certificates or beneficial owners of Warrants.


 


(c)
Counsel. The Warrant Agent may consult with counsel satisfactory to it, which may include counsel for the Company, and the written
advice of such counsel shall be full and complete authorization and protection in respect of any action taken, suffered or omitted
by it hereunder in good faith and in accordance with the advice of such counsel.


 


(d)
Documents. The Warrant Agent shall be protected and shall incur no liability for or in respect of any action taken or omitted
by it in reliance upon any Warrant Certificate, notice, direction, consent, certificate, affidavit, statement or other paper or
document reasonably believed by it to be genuine and to have been presented or signed by the proper parties.


 


(e)
Certain Transactions. The Warrant Agent, and its officers, directors and employees, may become the owner of, or acquire any interest
in, Warrants, with the same rights that it or they would have if it were not the Warrant Agent hereunder, and, to the extent permitted
by applicable law, it or they may engage or be interested in any financial or other transaction with the Company and may act on,
or as depositary, trustee or agent for, any committee or body of Holders of Warrant Securities or other obligations of the Company
as freely as if it were not the Warrant Agent hereunder. Nothing in this Warrant Agreement shall be deemed to prevent the Warrant
Agent from acting as trustee under any indenture to which the Company is a party.


 


(f)
No Liability for Interest. Unless otherwise agreed with the Company, the Warrant Agent shall have no liability for interest on
any monies at any time received by it pursuant to any of the provisions of this Agreement or of the Warrant Certificates.


 


(g)
No Liability for Invalidity. The Warrant Agent shall have no liability with respect to any invalidity of this Agreement or any
of the Warrant Certificates (except as to the Warrant Agent’s countersignature thereon).


 


(h)
No Responsibility for Representations. The Warrant Agent shall not be responsible for any of the recitals or representations herein
or in the Warrant Certificates (except as to the Warrant Agent’s countersignature thereon), all of which are made solely
by the Company.


 


(i)
No Implied Obligations. The Warrant Agent shall be obligated to perform only such duties as are herein and in the Warrants specifically
set forth and no implied duties or obligations shall be read into this Agreement or the Warrants against the Warrant Agent. The
Warrant Agent shall not be under any obligation to take any action hereunder which may tend to involve it in any expense or liability,
the payment of which within a reasonable time is not, in its reasonable opinion, assured to it. The Warrant Agent shall not be
accountable or under any duty or responsibility for the use by the Company of any of the Warrants authenticated by the Warrant
Agent and delivered by it to the Company pursuant to this Agreement or for the application by the Company of the proceeds of the
Warrants. The Warrant Agent shall have no duty or responsibility in case of any default by the Company in the performance of its
covenants or agreements contained herein or in the Warrants or in the case of the receipt of any written demand from a Holder
of a Warrant Certificate with respect to such default, including, without limiting the generality of the foregoing, any duty or
responsibility to initiate or attempt to initiate any proceedings at law.


 




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Section
15. Purchase or Consolidation or Change of Name of Warrant Agent. Any corporation into which the Warrant Agent or any successor
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 or any successor Warrant Agent shall be party, or any corporation succeeding to the corporate trust
business of the Warrant Agent or any successor Warrant Agent, shall be the successor to the Warrant Agent under this Agreement
without the execution or filing of any paper or any further act on the part of any of the parties hereto, provided that such corporation
would be eligible for appointment as a successor Warrant Agent under the provisions of Section 17. In case at the time such successor
Warrant Agent shall succeed to the agency created by this Agreement any of the Warrants shall have been countersigned but not
delivered, any such successor Warrant Agent may adopt the countersignature of the predecessor Warrant Agent and deliver such Warrants
so countersigned; and in case at that time any of the Warrants shall not have been countersigned, any successor Warrant Agent
may countersign such Warrants either in the name of the predecessor Warrant Agent or in the name of the successor Warrant Agent;
and in all such cases such Warrants shall have the full force provided in the Warrants and in this Agreement.


 


In
case at any time the name of the Warrant Agent shall be changed and at such time any of the Warrants shall have been countersigned
but not delivered, the Warrant Agent may adopt the countersignature under its prior name and deliver Warrants so countersigned;
and in case at that time any of the Warrants shall not have been countersigned, the Warrant Agent may countersign such Warrants
either in its prior name or in its changed name; and in all such cases such Warrants shall have the full force provided in the
Warrants and in this Agreement.


 


Section
16. Duties of Warrant Agent. The Warrant Agent undertakes the duties and obligations imposed by this Agreement upon the
following terms and conditions, by all of which the Company, by its acceptance hereof, shall be bound:


 


(a)
The Warrant Agent may consult with legal counsel reasonably acceptable to the Company (who may be legal counsel for the Company),
and the opinion of such counsel shall be full and complete authorization and protection to the Warrant Agent as to any action
taken or omitted by it in good faith and in accordance with such opinion.


 


(b)
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 certificate signed by the Chief Executive Officer or Chief Financial Officer of the Company; and such certificate shall be
full authentication to the Warrant Agent for any action taken or suffered in good faith by it under the provisions of this Agreement
in reliance upon such certificate.


 


(c)
Subject to the limitation set forth in Section 14, the Warrant Agent shall be liable hereunder only for its own gross negligence,
bad faith or willful misconduct, or for a breach by it of this Agreement.


 


(d)
The Warrant Agent shall not be liable for or by reason of any of the statements of fact or recitals contained in this Agreement
or in the Warrants (except its countersignature thereof) by the Company or be required to verify the same, but all such statements
and recitals are and shall be deemed to have been made by the Company only.


 


(e)
The Warrant Agent shall not be under any responsibility in respect of the validity of this Agreement or the execution and delivery
hereof (except the due execution hereof by the Warrant Agent) or in respect of 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 for the adjustment of the Exercise Price or the making of any
change in the number of shares of Common Stock required under the provisions of Section 11 or 13 or responsible for the manner,
method or amount of any such change or the ascertaining of the existence of facts that would require any such adjustment or change
(except with respect to the exercise of Warrants evidenced by Warrant Certificates after actual notice of any adjustment of the
Exercise Price); 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 duly authorized, validly issued, fully paid and nonassessable.


 




    	 	8	 



    	 



    

 


(f)
Each party hereto agrees that it will 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 other party hereto
for the carrying out or performing by any party of the provisions of this Agreement.


 


(g)
The Warrant Agent is hereby authorized to accept instructions with respect to the performance of its duties hereunder from the
Chief Executive Officer or Chief Financial Officer of the Company, and to apply to such officers for advice or instructions in
connection with its duties, and it shall not be liable and shall be indemnified and held harmless for any action taken or suffered
to be taken by it in good faith in accordance with instructions of any such officer, provided Warrant Agent carries out such instructions
without gross negligence, bad faith or willful misconduct.


 


(h)
The Warrant Agent and any shareholder, director, officer or employee of the Warrant Agent may buy, sell or deal in any of the
Warrants or other securities of the Company or become pecuniarily interested in any transaction in which the Company may be interested,
or contract with or lend money to the Company or otherwise act as fully and freely as though it were not Warrant Agent under this
Agreement. Nothing herein shall preclude the Warrant Agent from acting in any other capacity for the Company or for any other
legal entity.


 


(i)
The Warrant Agent may execute and exercise any of the rights or powers hereby vested in it or perform any duty hereunder either
itself or by or through its attorney or agents, and the Warrant Agent shall not be answerable or accountable for any act, default,
neglect or misconduct of any such attorney or agents or for any loss to the Company resulting from any such act, default, neglect
or misconduct, provided reasonable care was exercised in the selection and continued employment thereof.


 


Section
17. Change of Warrant Agent. The Warrant Agent may resign and be discharged from its duties under this Agreement upon 30
days’ notice in writing sent to the Company and to each transfer agent of the Common Stock, and to the Holders of the Warrant
Certificates. The Company may remove the Warrant Agent or any successor Warrant Agent upon 30 days’ notice in writing, sent
to the Warrant Agent or successor Warrant Agent, as the case may be, and to each transfer agent of the Common Stock, and to the
Holders of the Warrant Certificates. If the Warrant Agent shall resign or be removed or shall otherwise become incapable of acting,
the Company shall appoint a successor to the Warrant Agent. If the Company shall fail to make such appointment within a period
of 30 days after such removal or after it has been notified in writing of such resignation or incapacity by the resigning or incapacitated
Warrant Agent or by the Holder of a Warrant Certificate (who shall, with such notice, submit his Warrant Certificate for inspection
by the Company), then the Holder of any Warrant Certificate may apply to any court of competent jurisdiction for the appointment
of a new Warrant Agent. Any successor Warrant Agent, whether appointed by the Company or by such a court, shall be a corporation
organized and doing business under the laws of the United States or of a state thereof, in good standing, which is authorized
under such laws to exercise corporate trust powers and is subject to supervision or examination by federal or state authority
and which has at the time of its appointment as Warrant Agent a combined capital and surplus of at least $50,000,000. After appointment,
the successor Warrant Agent shall be vested with the same powers, rights, duties and responsibilities as if it had been originally
named as Warrant Agent without further act or deed; but the predecessor Warrant Agent shall deliver and transfer to the successor
Warrant Agent any property at the time held by it hereunder, and execute and deliver any further assurance, conveyance, act or
deed necessary for the purpose. Not later than the effective date of any such appointment, the Company shall file notice thereof
in writing with the predecessor Warrant Agent and each transfer agent of the Common Stock, and mail a notice thereof in writing
to the Holders of the Warrant Certificates. However, failure to give any notice provided for in this Section 17, or any defect
therein, shall not affect the legality or validity of the resignation or removal of the Warrant Agent or the appointment of the
successor Warrant Agent, as the case may be.


 


Section
18. Issuance of New Warrants. Notwithstanding any of the provisions of this Agreement or of the Warrants to the contrary,
the Company may, at its option, issue a new Global Warrant or Warrant Certificates, if any, evidencing Warrants in such form as
may be approved by its Board of Directors to reflect any adjustment or change in the Exercise Price per share and the number or
kind or class of shares of stock or other securities or property purchasable under the Global Warrant or Warrant Certificates,
if any, made in accordance with the provisions of this Agreement.


 




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Section
19. Notices. Notices or demands authorized by this Agreement to be given or made (i) by the Warrant Agent or by the Holder
of any Warrant Certificate to or on the Company, (ii) subject to the provisions of Section 17, by the Company or by the Holder
of any Warrant Certificate to or on the Warrant Agent or (iii) by the Company or the Warrant Agent to the Holder of any Warrant
Certificate, shall be deemed given (a) on the date delivered, if delivered personally, (b) on the first Business Day following
the deposit thereof with Federal Express or another recognized overnight courier, if sent by Federal Express or another recognized
overnight courier, (c) on the fourth Business Day following the mailing thereof with postage prepaid, if mailed by registered
or certified mail (return receipt requested), and (d) the date of transmission, if such notice or communication is delivered via
facsimile or email attachment at or prior to 5:30 p.m. (New York City time) on a Business Day and (e) the next Business Day after
the date of transmission, if such notice or communication is delivered via facsimile or email attachment on a day that is not
a Business Day or later than 5:30 p.m. (New York City time) on any Business Day, in each case to the parties at the following
addresses (or at such other address for a party as shall be specified by like notice):


 


(a)
If to the Company, to:


 


Hemispherx
Biopharma, Inc.


2117
SW Highway 484


Ocala,
FL 34473


Facsimile:
352-480-4620


Attention:
Thomas K. Equels, Chief Executive Officer


 


(b)
If to the Warrant Agent, to:


 


American
Stock Transfer & Trust Company, LLC


6201
15th Avenue, Brooklyn, NY 11219


Attention:
Sharon Best-Jhagroo


 


(c)
If to the Holder of any Warrant Certificate, to the address of such Holder as shown on the registry books of the Company. Any
notice required to be delivered by the Company to the Holder of any Warrant may be given by the Warrant Agent on behalf of the
Company. Notwithstanding any other provision of this Agreement, where this Agreement provides for notice of any event to a Holder
of any Warrant Certificate, for a Global Warrant, such notice shall be sufficiently given if given to the Depositary (or its designee)
pursuant to the procedures of the Depositary or its designee


 


For
any notice delivered by email to be deemed given or made, such notice must be followed by notice sent by overnight courier service
to be delivered on the next business day following such email, unless the recipient of such email has acknowledged via return
email receipt of such email.


 


Section
20. Supplements and Amendments.


 


(a)
The Company and the Warrant Agent may from time to time supplement or amend this Agreement without the approval of any Holders
of Warrant Certificates in order to cure any ambiguity, to correct or supplement any provision contained herein which may be defective
or inconsistent with any other provisions herein, or to make any other provisions with regard to matters or questions arising
hereunder which the Company and the Warrant Agent may deem necessary or desirable and which shall not adversely affect the interests
of the Holders of the Warrants Certificates in any material respect.


 


(b)
In addition to the foregoing, with the consent of Holders of Warrants, the Company and the Warrant Agent may modify this Agreement
for the purpose of adding any provisions to or changing in any manner or eliminating any of the provisions of this Warrant Agreement
or modifying in any manner the rights of the Holders of the Warrant Certificates; provided, however, that no modification
of the terms (including but not limited to the adjustments described in Section 11) upon which the Warrants are exercisable or
reducing the percentage required for consent to modification of this Agreement may be made without the consent of the Holder of
each outstanding warrant certificate affected thereby. As a condition precedent to the Warrant Agent’s execution of any
amendment, the Company shall deliver to the Warrant Agent a certificate from a duly authorized officer of the Company that states
that the proposed amendment complies with the terms of this Section 20.


 


Section
21. Successors. All 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 hereunder.


 


Section
22. Benefits of this Agreement. Nothing in this Agreement shall be construed to give any Person other than the Company,
the Holders of Warrant Certificates and the Warrant Agent any legal or equitable right, remedy or claim under this Agreement;
but this Agreement shall be for the sole and exclusive benefit of the Company, the Warrant Agent and the Holders of the Warrant
Certificates.


 




    	 	10	 



    	 



    

 


Section
23. Governing Law. This Agreement and each Warrant issued hereunder shall be governed by, and construed in accordance with,
the laws of the State of New York without giving effect to the conflicts of law principles thereof.


 


Section
24. Counterparts. This Agreement may be executed in any number of 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.


 


Section
25. Captions. The captions of the sections of this Agreement have been inserted for convenience only and shall not control
or affect the meaning or construction of any of the provisions hereof.


 


Section
26. Information. The Company agrees to promptly provide to the Holders of the Warrants any information it provides to all
holders of the Common Stock, except to the extent any such information is publicly available on the EDGAR system (or any successor
thereof) of the Securities and Exchange Commission.


 


Section
27. Force Majeure. Notwithstanding anything to the contrary contained herein, Warrant Agent shall not be liable for any
delays or failures in performance resulting from acts beyond its reasonable control including, without limitation, acts of God,
terrorist acts, shortage of supply, breakdowns or malfunctions, interruptions or malfunction of computer facilities, or loss of
data due to power failures or mechanical difficulties with information storage or retrieval systems, labor difficulties, war,
or civil unrest, it being understood that the Warrant Agent shall use reasonable best efforts which are consistent with accepted
practices in the banking industry to resume performance as soon as practicable under the circumstances.


 


[Signature
Page to Follow]


 




    	 	11	 



    	 



    

 


IN
WITNESS WHEREOF, the parties hereto have caused this Agreement to be duly executed as of the day and year first above written.


 


	 	Hemispherx Biopharma, Inc.
	 	 	 
	 	By:
    	/s/
    Adam Pascale
	 	 	Adam
    Pascale, CFO
	 	 	 
	 	American Stock Transfer & Trust Company, LLC
	 	 	 
	 	By:
    	/s/
    Michael Legregin
	 	Name:
    	Michael Legregin
	 	Title:
    	SVP


 




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Annex
A: Form of Warrant Certificate Request Notice


 


WARRANT
CERTIFICATE REQUEST NOTICE


 


To:
American Stock Transfer & Trust Company, LLC as Warrant Agent for Hemispherx Biopharma, Inc. (the “Company”)


 


The
undersigned Holder of Common Stock Purchase Warrants (“Warrants”) in the form of Global Warrants issued by the Company
hereby elects to receive a Warrant Certificate evidencing the Warrants held by the Holder as specified below:


 


	1.	Name
    of Holder of Warrants in form of Global Warrants: _____________________________
	 	 
	2.	Name
    of Holder in Warrant Certificate (if different from name of Holder of Warrants in form of Global Warrants): ________________________________
	 	 
	3.	Number
    of Warrants in name of Holder in form of Global Warrants: ___________________
	 	 
	4.	Number
    of Warrants for which Warrant Certificate shall be issued: __________________
	 	 
	5.	Number
    of Warrants in name of Holder in form of Global Warrants after issuance of Warrant Certificate, if any: ___________


 


	6.	Warrant
    Certificate shall be delivered to the following address:


 


	 	 
	 	 
	 	 
	 	 
	 	 
	 	 
	 	 


 


The
undersigned hereby acknowledges and agrees that, in connection with this Warrant Exchange and the issuance of the Warrant Certificate,
the Holder is deemed to have surrendered the number of Warrants in form of Global Warrants in the name of the Holder equal to
the number of Warrants evidenced by the Warrant Certificate.


 


[SIGNATURE
OF HOLDER]


 


Name
of Investing Entity: ____________________________________________________


 


Signature
of Authorized Signatory of Investing Entity: ______________________________


 


Name
of Authorized Signatory: ________________________________________________


 


Title
of Authorized Signatory: _________________________________________________


 


Date:
_______________________________________________________________


 




    	 	 	 



    	 



    

 


Exhibit
1: Form of Warrant