Exhibit
4.2


 


NEITHER
THIS SECURITY NOR THE SECURITIES FOR WHICH THIS SECURITY IS EXERCISABLE HAVE BEEN REGISTERED WITH THE SECURITIES AND EXCHANGE
COMMISSION OR THE SECURITIES COMMISSION OF ANY STATE IN RELIANCE UPON AN EXEMPTION FROM REGISTRATION UNDER THE SECURITIES ACT
OF 1933, AS AMENDED (THE “SECURITIES ACT”), AND, ACCORDINGLY, MAY NOT BE OFFERED OR SOLD EXCEPT PURSUANT TO AN EFFECTIVE
REGISTRATION STATEMENT UNDER THE SECURITIES ACT OR PURSUANT TO AN AVAILABLE EXEMPTION FROM, OR IN A TRANSACTION NOT SUBJECT TO,
THE REGISTRATION REQUIREMENTS OF THE SECURITIES ACT AND IN ACCORDANCE WITH APPLICABLE STATE SECURITIES LAWS. THIS SECURITY AND
THE SECURITIES ISSUABLE UPON EXERCISE OF THIS SECURITY MAY BE PLEDGED IN CONNECTION WITH A BONA FIDE MARGIN ACCOUNT OR OTHER LOAN
SECURED BY SUCH SECURITIES


 


CLASS
B COMMON STOCK PURCHASE WARRANT


 


hemispherx
biopharma, inc.


 


	Warrant
    Shares:	Initial
    Exercise Date: October 24, 2018
	 	Issue
    Date: April 24, 2018


 


THIS
CLASS B COMMON STOCK PURCHASE WARRANT (the “Warrant”) certifies that, for value received, ___________________________
or its assigns (the “Holder”) is entitled, upon the terms and subject to the limitations on exercise and the
conditions hereinafter set forth, at any time on or after October 24, 2018 (the “Initial Exercise Date”)
and on or prior to the close of business on five (5) year anniversary of the Initial Exercise Date (the “Termination
Date”) but not thereafter, to subscribe for and purchase from Hemispherx BioPharma, Inc., a Delaware corporation (the
“Company”), up to ______ shares (as subject to adjustment hereunder, the “Warrant Shares”)
of Common Stock. The purchase price of one share of Common Stock under this Warrant shall be equal to the Exercise Price, as defined
in Section 2(b).


 


Section
1. Definitions. Capitalized terms used and not otherwise defined herein shall have the meanings set forth in that certain
Securities Purchase Agreement (the “Purchase Agreement”), dated April 20, 2018, among the Company and
the purchasers signatory thereto.










 




    	 	1	 



     


    

 


Section
2. Exercise.


 


a)
Exercise of Warrant. Exercise of the purchase rights represented by this Warrant may be made, in whole or in part, at any
time or times on or after the Initial Exercise Date and on or before the Termination Date by delivery to the Company or the Transfer
Agent (or such other office or agency that the Company may designate by notice in writing to the registered Holder at the address
of the Holder appearing on the books of the Company), as applicable, of a duly executed facsimile copy or PDF copy submitted by
e-mail (or e-mail attachment) of the Notice of Exercise in the form annexed hereto (the “Notice of Exercise”).
Within the earlier of (i) two (2) Trading Days and (ii) the number of Trading Days comprising the Standard Settlement Period
(as defined in Section 2(d)(i) herein) following the date of exercise as aforesaid, the Holder shall deliver the aggregate Exercise
Price for the shares specified in the applicable Notice of Exercise by wire transfer or cashier’s check drawn on a United
States bank unless the cashless exercise procedure specified in Section 2(c) below is specified in the applicable Notice of Exercise.
No ink-original Notice of Exercise shall be required, nor shall any medallion guarantee (or other type of guarantee or notarization)
of any Notice of Exercise form be required. Notwithstanding anything herein to the contrary, the Holder shall not be required
to physically surrender this Warrant to the Company until the Holder has purchased all of the Warrant Shares available hereunder
and the Warrant has been exercised in full, in which case, the Holder shall surrender this Warrant to the Company for cancellation
within three (3) Trading Days of the date the final Notice of Exercise is delivered to the Company. Partial exercises of this
Warrant resulting in purchases of a portion of the total number of Warrant Shares available hereunder shall have the effect of
lowering the outstanding number of Warrant Shares purchasable hereunder in an amount equal to the applicable number of Warrant
Shares purchased. The Holder and the Company shall maintain records showing the number of Warrant Shares purchased and the date
of such purchases. The Company shall deliver any objection to any Notice of Exercise within one (1) Business Day of receipt of
such notice. The Holder and any assignee, by acceptance of this Warrant, acknowledge and agree that, by reason of the provisions
of this paragraph, following the purchase of a portion of the Warrant Shares hereunder, the number of Warrant Shares available
for purchase hereunder at any given time may be less than the amount stated on the face hereof.


 


b)
Exercise Price. The exercise price per share of the Common Stock under this Warrant shall be $0.39, subject to adjustment
hereunder (the “Exercise Price”).


 


c)
Cashless Exercise. If at any time after the six-month anniversary of the Closing Date, there is no effective registration
statement registering, or no current prospectus available for, the resale of the Warrant Shares by the Holder, then this Warrant
may also be exercised, in whole or in part, at such time by means of a “cashless exercise” in which the Holder shall
be entitled to receive a number of Warrant Shares equal to the quotient obtained by dividing [(A-B) (X)] by (A), where:


 


(A)
= as applicable: (i) the VWAP on the Trading Day immediately preceding the date of the applicable Notice of Exercise if such Notice
of Exercise is (1) both executed and delivered pursuant to Section 2(a) hereof on a day that is not a Trading Day or (2) both
executed and delivered pursuant to Section 2(a) hereof on a Trading Day prior to the opening of “regular trading hours”
(as defined in Rule 600(b)(64) of Regulation NMS promulgated under the federal securities laws) on such Trading Day, (ii) at the
option of the Holder, either (y) the VWAP on the Trading Day immediately preceding the date of the applicable Notice of Exercise
or (z) the Bid Price of the Common Stock on the principal Trading Market as reported by Bloomberg L.P. as of the time of the Holder’s
execution of the applicable Notice of Exercise if such Notice of Exercise is executed during “regular trading hours”
on a Trading Day and is delivered within two (2) hours thereafter (including until two (2) hours after the close of “regular
trading hours” on a Trading Day) pursuant to Section 2(a) hereof or (iii) the VWAP on the date of the applicable Notice
of Exercise if the date of such Notice of Exercise is a Trading Day and such Notice of Exercise is both executed and delivered
pursuant to Section 2(a) hereof after the close of “regular trading hours” on such Trading Day;


 




    	 	2	 



     


    




 


(B)
= the Exercise Price of this Warrant, as adjusted hereunder; and


 


(X)
= the number of Warrant Shares that would be issuable upon exercise of this Warrant in accordance with the terms of this Warrant
if such exercise were by means of a cash exercise rather than a cashless exercise.


 


If
Warrant Shares are issued in such a cashless exercise, the parties acknowledge and agree that in accordance with Section 3(a)(9)
of the Securities Act, the Warrant Shares shall take on the characteristics of the Warrants being exercised, and the holding period
of the Warrant Shares being issued may be tacked on to the holding period of this Warrant. The Company agrees not to take any
position contrary to this Section 2(c).


 


“Bid
Price” 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 a Trading Market, the bid price of the Common Stock for the time in question (or the nearest
preceding date) on the Trading Market on which the Common Stock is then listed or quoted as reported by Bloomberg L.P. (based
on a Trading Day from 9:30 a.m. (New York City time) to 4:02 p.m. (New York City time)), (b) if OTCQB or OTCQX is not a Trading
Market, the volume weighted average price of the Common Stock for such date (or the nearest preceding date) on OTCQB or OTCQX
as applicable, (c) if the Common Stock is not then listed or quoted for trading on 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 most recent bid price per share of the Common Stock so reported, or (d)
in all other cases, the fair market value of a share of Common Stock as determined by an independent appraiser selected in good
faith by the Purchasers of a majority in interest of the Securities then outstanding and reasonably acceptable to the Company,
the fees and expenses of which shall be paid by the Company.


 


“VWAP”
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 a Trading Market, the daily volume weighted average price of the Common Stock for such date (or the nearest
preceding date) on the Trading Market on which the Common Stock is then listed or quoted as reported by Bloomberg L.P. (based
on a Trading Day from 9:30 a.m. (New York City time) to 4:02 p.m. (New York City time)), (b) if OTCQB or OTCQX is not a Trading
Market, the volume weighted average price of the Common Stock for such date (or the nearest preceding date) on OTCQB or OTCQX
as applicable, (c) if the Common Stock is not then listed or quoted for trading on 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 most recent bid price per share of the Common Stock so reported, or (d)
in all other cases, the fair market value of a share of Common Stock as determined by an independent appraiser selected in good
faith by the Purchasers of a majority in interest of the Securities then outstanding and reasonably acceptable to the Company,
the fees and expenses of which shall be paid by the Company.


 




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Notwithstanding
anything herein or in the Purchase Agreement to the contrary, on the Termination Date, this Warrant shall be automatically exercised
via cashless exercise pursuant to Section 2(c).


 


	 	d)	Mechanics
    of Exercise.


 


	 	i.	Delivery
                                         of Warrant Shares Upon Exercise. Warrant Shares purchased hereunder shall be transmitted
                                         by the Transfer Agent to the Holder by crediting the account of the Holder’s or
                                         its designee’s balance account with The Depository Trust Company through its Deposit
                                         or Withdrawal at Custodian system (“DWAC”) if the Company is then
                                         a participant in such system and either (A) there is an effective registration statement
                                         permitting the issuance of the Warrant Shares to or resale of the Warrant Shares by the
                                         Holder or (B) the Warrant Shares are eligible for resale by the Holder without volume
                                         or manner-of-sale limitations pursuant to Rule 144 (assuming cashless exercise of this
                                         Warrant), and otherwise by physical delivery of a certificate, registered in the Company’s
                                         share register in the name of the Holder or its designee, for the number of Warrant Shares
                                         to which the Holder is entitled pursuant to such exercise to the address specified by
                                         the Holder in the Notice of Exercise by the date that is the earliest of (i) two (2)
                                         Trading Days, (iii) one (1) Trading Day after delivery of the aggregate Exercise
                                         Price to the Company and (iii) the number of Trading Days comprising the Standard Settlement
                                         Period after the delivery to the Company of the Notice of Exercise (such date, the “Warrant
                                         Share Delivery Date”); provided, under no circumstances is the Company required
                                         to cause the Warrant Shares to be delivered prior to payment of the aggregate Exercise
                                         Price (other than in the case of a cashless exercise). Upon delivery of the Notice of
                                         Exercise, the Holder shall be deemed for all corporate purposes to have become the holder
                                         of record of the Warrant Shares with respect to which this Warrant has been exercised,
                                         irrespective of the date of delivery of the Warrant Shares, provided that payment of
                                         the aggregate Exercise Price (other than in the case of a cashless exercise) is received
                                         within the earlier of (i) two (2) Trading Days and (ii) the number of Trading
                                         Days comprising the Standard Settlement Period following delivery of the Notice of Exercise.
                                         If the Company fails for any reason to deliver to the Holder the Warrant Shares subject
                                         to a Notice of Exercise by the Warrant Share Delivery Date and the applicable aggregate
                                         Exercise Price has been delivered (other than in the case of a cashless exercise), the
                                         Company shall pay to the Holder, in cash, as liquidated damages and not as a penalty,
                                         for each $1,000 of Warrant Shares subject to such exercise (based on the VWAP of the
                                         Common Stock on the date of the applicable Notice of Exercise), $10 per Trading Day (increasing
                                         to $20 per Trading Day on the fifth Trading Day after such liquidated damages begin to
                                         accrue) for each Trading Day after such Warrant Share Delivery Date until such Warrant
                                         Shares are delivered or Holder rescinds such exercise. The Company agrees to maintain
                                         a transfer agent that is a participant in the FAST program so long as this Warrant remains
                                         outstanding and exercisable. As used herein, “Standard Settlement Period”
                                         means the standard settlement period, expressed in a number of Trading Days, on the Company’s
                                         primary Trading Market with respect to the Common Stock as in effect on the date of delivery
                                         of the Notice of Exercise.







 




    	 	4	 



     


    

 


ii.
Delivery of New Warrants Upon Exercise. If this Warrant shall have been exercised in part, the Company shall, at the request
of a Holder and upon surrender of this Warrant certificate, at the time of delivery of the Warrant Shares, deliver to the Holder
a new Warrant evidencing the rights of the Holder to purchase the unpurchased Warrant Shares called for by this Warrant, which
new Warrant shall in all other respects be identical with this Warrant.


 


iii.
Rescission Rights. If the Company fails to cause the Transfer Agent to transmit to the Holder the Warrant Shares pursuant
to Section 2(d)(i) by the Warrant Share Delivery Date, then the Holder will have the right to rescind such exercise.


 


iv.
Compensation for Buy-In on Failure to Timely Deliver Warrant Shares Upon Exercise. In addition to any other rights available
to the Holder, if the Company fails to cause the Transfer Agent to transmit to the Holder the Warrant Shares in accordance with
the provisions of Section 2(d)(i) above pursuant to an exercise on or before the Warrant Share Delivery Date, and if after such
date the Holder is required by its broker to purchase (in an open market transaction or otherwise) or the Holder’s brokerage
firm otherwise purchases, shares of Common Stock to deliver in satisfaction of a sale by the Holder of the Warrant Shares which
the Holder anticipated receiving upon such exercise (a “Buy-In”), then the Company shall (A) pay in cash to
the Holder the amount, if any, by which (x) the Holder’s total purchase price (including brokerage commissions, if any)
for the shares of Common Stock so purchased exceeds (y) the amount obtained by multiplying (1) the number of Warrant Shares that
the Company was required to deliver to the Holder in connection with the exercise at issue times (2) the price at which the sell
order giving rise to such purchase obligation was executed, and (B) at the option of the Holder, either reinstate the portion
of the Warrant and equivalent number of Warrant Shares for which such exercise was not honored (in which case such exercise shall
be deemed rescinded) or deliver to the Holder the number of shares of Common Stock that would have been issued had the Company
timely complied with its exercise and delivery obligations hereunder. For example, if the Holder purchases Common Stock having
a total purchase price of $11,000 to cover a Buy-In with respect to an attempted exercise of shares of Common Stock with an aggregate
sale price giving rise to such purchase obligation of $10,000, under clause (A) of the immediately preceding sentence the Company
shall be required to pay the Holder $1,000. The Holder shall provide the Company written notice indicating the amounts payable
to the Holder in respect of the Buy-In and, upon request of the Company, evidence of the amount of such loss. Nothing herein shall
limit a Holder’s right to pursue any other remedies available to it hereunder, at law or in equity including, without limitation,
a decree of specific performance and/or injunctive relief with respect to the Company’s failure to timely deliver shares
of Common Stock upon exercise of the Warrant as required pursuant to the terms hereof.


 




    	 	5	 



     


    

 


v.
No Fractional Shares or Scrip. No fractional shares or scrip representing fractional shares shall be issued upon the exercise
of this Warrant. As to any fraction of a share which the Holder would otherwise be entitled to purchase upon such exercise, the
Company shall, at its election, either pay a cash adjustment in respect of such final fraction in an amount equal to such fraction
multiplied by the Exercise Price or round up to the next whole share.


 


vi.
Charges, Taxes and Expenses. Issuance of Warrant Shares shall be made without charge to the Holder for any issue or transfer
tax or other incidental expense in respect of the issuance of such Warrant Shares, all of which taxes and expenses shall be paid
by the Company, and such Warrant Shares shall be issued in the name of the Holder or in such name or names as may be directed
by the Holder; provided, however, that in the event that Warrant Shares are to be issued in a name other than the
name of the Holder, this Warrant when surrendered for exercise shall be accompanied by the Assignment Form attached hereto duly
executed by the Holder and the Company may require, as a condition thereto, the payment of a sum sufficient to reimburse it for
any transfer tax incidental thereto. The Company shall pay all Transfer Agent fees required for same-day processing of any Notice
of Exercise and all fees to the Depository Trust Company (or another established clearing corporation performing similar functions)
required for same-day electronic delivery of the Warrant Shares.


 


vii.
Closing of Books. The Company will not close its stockholder books or records in any manner which prevents the timely exercise
of this Warrant, pursuant to the terms hereof.


 




    	 	6	 



     


    

 


e)
Holder’s Exercise Limitations. The Company shall not effect any exercise of this Warrant, and a Holder shall not
have the right to exercise any portion of this Warrant, pursuant to Section 2 or otherwise, to the extent that after giving effect
to such issuance after exercise as set forth on the applicable Notice of Exercise, the Holder (together with the Holder’s
Affiliates, and any other Persons acting as a group together with the Holder or any of the Holder’s Affiliates (such Persons,
“Attribution Parties”)), would beneficially own in excess of the Beneficial Ownership Limitation (as defined
below). For purposes of the foregoing sentence, the number of shares of Common Stock beneficially owned by the Holder and its
Affiliates and Attribution Parties shall include the number of shares of Common Stock issuable upon exercise of this Warrant with
respect to which such determination is being made, but shall exclude the number of shares of Common Stock which would be issuable
upon (i) exercise of the remaining, nonexercised portion of this Warrant beneficially owned by the Holder or any of its Affiliates
or Attribution Parties and (ii) exercise or conversion of the unexercised or nonconverted portion of any other securities of the
Company (including, without limitation, any other Common Stock Equivalents) subject to a limitation on conversion or exercise
analogous to the limitation contained herein beneficially owned by the Holder or any of its Affiliates or Attribution Parties.
Except as set forth in the preceding sentence, for purposes of this Section 2(e), beneficial ownership shall be calculated in
accordance with Section 13(d) of the Exchange Act and the rules and regulations promulgated thereunder, it being acknowledged
by the Holder that the Company is not representing to the Holder that such calculation is in compliance with Section 13(d) of
the Exchange Act and the Holder is solely responsible for any schedules required to be filed in accordance therewith. To the extent
that the limitation contained in this Section 2(e) applies, the determination of whether this Warrant is exercisable (in relation
to other securities owned by the Holder together with any Affiliates and Attribution Parties) and of which portion of this Warrant
is exercisable shall be in the sole discretion of the Holder, and the submission of a Notice of Exercise shall be deemed to be
the Holder’s determination of whether this Warrant is exercisable (in relation to other securities owned by the Holder together
with any Affiliates and Attribution Parties) and of which portion of this Warrant is exercisable, in each case subject to the
Beneficial Ownership Limitation, and the Company shall have no obligation to verify or confirm the accuracy of such determination
and shall have no liability for exercises of the Warrant that are not in compliance with the Beneficial Ownership Limitation,
other than with respect to exercises of the Warrant not in compliance with the Beneficial Ownership Limit as a result of incorrect
information regarding the number of outstanding shares of Common Stock provided to the Holder by the Company pursuant to this
Section 2(e). In addition, a determination as to any group status as contemplated above shall be determined in accordance with
Section 13(d) of the Exchange Act and the rules and regulations promulgated thereunder, and the Company shall have no obligation
to verify or confirm the accuracy of such determination and shall have no liability for exercises of the Warrant that are not
in compliance with the Beneficial Ownership Limitation, other than with respect to exercises of the Warrant not in compliance
with the Beneficial Ownership Limit as a result of incorrect information regarding the number of outstanding shares of Common
Stock provided to the Holder by the Company pursuant to this Section 2(e). For purposes of this Section 2(e), in determining the
number of outstanding shares of Common Stock, a Holder may rely on the number of outstanding shares of Common Stock as reflected
in (A) the Company’s most recent periodic or annual report filed with the Commission, as the case may be, (B) a more recent
public announcement by the Company or (C) a more recent written notice by the Company or the Transfer Agent setting forth the
number of shares of Common Stock outstanding. Upon the written request of a Holder, the Company shall within two Trading Days
confirm orally and in writing to the 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 securities of the
Company, including this Warrant, by the Holder or its Affiliates or Attribution Parties since the date as of which such number
of outstanding shares of Common Stock was reported. The “Beneficial Ownership Limitation” shall be 4.99% of
the number of shares of the Common Stock outstanding immediately after giving effect to the issuance of shares of Common Stock
issuable upon exercise of this Warrant. The Holder, upon notice to the Company, may increase or decrease the Beneficial Ownership
Limitation provisions of this Section 2(e), provided that the Beneficial Ownership Limitation in no event exceeds 9.99% of the
number of shares of the Common Stock outstanding immediately after giving effect to the issuance of shares of Common Stock upon
exercise of this Warrant held by the Holder and the provisions of this Section 2(e) shall continue to apply. Any increase in the
Beneficial Ownership Limitation will not be effective until the 61st day after such notice is delivered to the Company.
The provisions of this paragraph shall be construed and implemented in a manner otherwise than in strict conformity with the terms
of this Section 2(e) to correct this paragraph (or any portion hereof) which may be defective or inconsistent with the intended
Beneficial Ownership Limitation herein contained or to make changes or supplements necessary or desirable to properly give effect
to such limitation. The limitations contained in this paragraph shall apply to a successor holder of this Warrant.


 




    	 	7	 



     


    

 


Section
3. Certain Adjustments.


 


a)
Stock Dividends and Splits. If the Company, at any time while this Warrant is outstanding: (i) pays a stock dividend or
otherwise makes a distribution or distributions on shares of its Common Stock or any other equity or equity equivalent securities
payable in shares of Common Stock (which, for avoidance of doubt, shall not include any shares of Common Stock issued by the Company
upon exercise of this Warrant), (ii) subdivides outstanding shares of Common Stock into a larger number of shares, (iii) combines
(including by way of reverse stock split) outstanding shares of Common Stock into a smaller number of shares or (iv) issues by
reclassification of shares of the Common Stock any shares of capital stock of the Company, then in each case the Exercise Price
shall be multiplied by a fraction of which the numerator shall be the number of shares of Common Stock (excluding treasury shares,
if any) outstanding immediately before such event and of which the denominator shall be the number of shares of Common Stock outstanding
immediately after such event, and the number of shares issuable upon exercise of this Warrant shall be proportionately adjusted
such that the aggregate Exercise Price of this Warrant shall remain unchanged. Any adjustment made pursuant to this Section 3(a)
shall become effective immediately after the record date for the determination of stockholders entitled to receive such dividend
or distribution and shall become effective immediately after the effective date in the case of a subdivision, combination or re-classification.


 


b)
Reserved


 


c)
Subsequent Rights Offerings. In addition to any adjustments pursuant to Section 3(a) above, if at any time the Company
grants, issues or sells any Common Stock Equivalents or rights to purchase stock, warrants, securities or other property pro rata
to the record holders of any class of shares of Common Stock (the “Purchase Rights”), then the Holder will
be entitled to acquire, upon the terms applicable to such Purchase Rights, the aggregate Purchase Rights which the Holder could
have acquired if the Holder had held the number of shares of Common Stock acquirable upon complete exercise of this Warrant (without
regard to any limitations on exercise hereof, including without limitation, the Beneficial Ownership Limitation) immediately before
the date on which a record is taken for the grant, issuance or sale of such Purchase Rights, or, if no such record is taken, the
date as of which the record holders of shares of Common Stock are to be determined for the grant, issue or sale of such Purchase
Rights (provided, however, to the extent that the Holder’s right to participate in any such Purchase Right would result
in the Holder exceeding the Beneficial Ownership Limitation, then the Holder shall not be entitled to participate in such Purchase
Right to such extent (or beneficial ownership of such shares of Common Stock as a result of such Purchase Right to such extent)
and such Purchase Right to such extent shall be held in abeyance for the Holder until such time, if ever, as its right thereto
would not result in the Holder exceeding the Beneficial Ownership Limitation).


 


d)
Pro Rata Distributions. During such time as this Warrant is outstanding, if the Company shall declare or make any dividend
or other distribution of its assets (or rights to acquire its assets) to holders of shares of Common Stock, by way of return of
capital or otherwise (including, without limitation, any distribution of cash, stock or other securities, property or options
by way of a dividend, spin off, reclassification, corporate rearrangement, scheme of arrangement or other similar transaction)
(a “Distribution”), at any time after the issuance of this Warrant, then, in each such case, the Holder shall
be entitled to participate in such Distribution to the same extent that the Holder would have participated therein if the Holder
had held the number of shares of Common Stock acquirable upon complete exercise of this Warrant (without regard to any limitations
on exercise hereof, including without limitation, the Beneficial Ownership Limitation) immediately before the date of which a
record is taken for such Distribution, or, if no such record is taken, the date as of which the record holders of shares of Common
Stock are to be determined for the participation in such Distribution (provided, however, to the extent that the
Holder’s right to participate in any such Distribution would result in the Holder exceeding the Beneficial Ownership Limitation,
then the Holder shall not be entitled to participate in such Distribution to such extent (or in the beneficial ownership of any
shares of Common Stock as a result of such Distribution to such extent) and the portion of such Distribution shall be held in
abeyance for the benefit of the Holder until such time, if ever, as its right thereto would not result in the Holder exceeding
the Beneficial Ownership Limitation).


 




    	8



    	 



    

 


e)
Fundamental Transaction. If, at any time while this Warrant is outstanding, (i) the Company, directly or indirectly, in
one or more related transactions effects any merger or consolidation of the Company with or into another Person, (ii) the Company,
directly or indirectly, effects any sale, lease, license, assignment, transfer, conveyance or other disposition of all or substantially
all of its assets in one or a series of related transactions, (iii) any, direct or indirect, purchase offer, tender offer or exchange
offer (whether by the Company or another Person) is completed pursuant to which holders of Common Stock are permitted to sell,
tender or exchange their shares for other securities, cash or property and has been accepted by the holders of 50% or more of
the outstanding Common Stock, (iv) the Company, directly or indirectly, in one or more related transactions effects any reclassification,
reorganization or recapitalization of the Common Stock or any compulsory share exchange pursuant to which the Common Stock is
effectively converted into or exchanged for other securities, cash or property, or (v) the Company, directly or indirectly, in
one or more related transactions consummates a stock or share purchase agreement or other business combination (including, without
limitation, a reorganization, recapitalization, spin-off or scheme of arrangement) with another Person or group of Persons whereby
such other Person or group acquires more than 50% of the outstanding shares of Common Stock (not including any shares of Common
Stock held by the other Person or other Persons making or party to, or associated or affiliated with the other Persons making
or party to, such stock or share purchase agreement or other business combination) (each a “Fundamental Transaction”),
then, upon any subsequent exercise of this Warrant, the Holder shall have the right to receive, for each Warrant Share that would
have been issuable upon such exercise immediately prior to the occurrence of such Fundamental Transaction, at the option of the
Holder (without regard to any limitation in Section 2(e) on the exercise of this Warrant), the number of shares of Common Stock
of the successor or acquiring corporation or of the Company, if it is the surviving corporation, and any additional consideration
(the “Alternate Consideration”) receivable as a result of such Fundamental Transaction by a holder of the number
of shares of Common Stock for which this Warrant is exercisable immediately prior to such Fundamental Transaction (without regard
to any limitation in Section 2(e) on the exercise of this Warrant). For purposes of any such exercise, the determination of the
Exercise Price shall be appropriately adjusted to apply to such Alternate Consideration based on the amount of Alternate Consideration
issuable in respect of one share of Common Stock in such Fundamental Transaction, and the Company shall apportion the Exercise
Price among the Alternate Consideration in a reasonable manner reflecting the relative value of any different components of the
Alternate Consideration. If holders of Common Stock are given any choice as to the securities, cash or property to be received
in a Fundamental Transaction, then the Holder shall be given the same choice as to the Alternate Consideration it receives upon
any exercise of this Warrant following such Fundamental Transaction. Notwithstanding anything to the contrary, in the event of
a Fundamental Transaction, the Company or any Successor Entity (as defined below) shall, at the Holder’s option, exercisable
at any time concurrently with, or within 30 days after, the consummation of the Fundamental Transaction (of, if later, the
date of the public announcement of the applicable Fundamental Transaction), purchase this Warrant from the Holder by paying
to the Holder an amount of cash equal to the Black Scholes Value of the remaining unexercised portion of this Warrant on the date
of the consummation of such Fundamental Transaction. “Black Scholes Value” means the value of this Warrant
based on the Black and Scholes Option Pricing Model obtained from the “OV” function on Bloomberg, L.P. (“Bloomberg”)
determined as of the day of consummation of the applicable Fundamental Transaction for pricing purposes and reflecting (A) a risk-free
interest rate corresponding to the U.S. Treasury rate for a period equal to the time between the date of the public announcement
of the applicable Fundamental Transaction and the Termination Date, (B) an expected volatility equal to the greater of 100% and
the 100 day volatility obtained from the HVT function on Bloomberg as of the Trading Day immediately following the public
announcement of the applicable Fundamental Transaction, (C) the underlying price per share used in such calculation shall be the
greater of (i) the sum of the price per share being offered in cash, if any, plus the value of any non-cash consideration,
if any, being offered in such Fundamental Transaction (ii) the greater of (x) the last VWAP immediately prior to the public
announcement of such Fundamental Transaction and (y) the last VWAP immediately prior to the consummation of such Fundamental Transaction
and (D) a remaining option time equal to the time between the date of the public announcement of the applicable Fundamental
Transaction and the Termination Date. The payment of the Black Scholes Value will be made by wire transfer of immediately available
funds within five Business Days of the Holder’s election (or, if later, on the effective date of the Fundamental Transaction).
The Company shall cause any successor entity in a Fundamental Transaction in which the Company is not the survivor (the “Successor
Entity”) to assume in writing all of the obligations of the Company under this Warrant and the other Transaction Documents
in accordance with the provisions of this Section 3(e) pursuant to written agreements in form and substance reasonably satisfactory
to the Holder and approved by the Holder (without unreasonable delay) prior to such Fundamental Transaction and shall, at the
option of the Holder, deliver to the Holder in exchange for this Warrant a security of the Successor Entity evidenced by a written
instrument substantially similar in form and substance to this Warrant which is exercisable for a corresponding number of shares
of capital stock of such Successor Entity (or its parent entity) equivalent to the shares of Common Stock acquirable and receivable
upon exercise of this Warrant (without regard to any limitations on the exercise of this Warrant) prior to such Fundamental Transaction,
and with an exercise price which applies the exercise price hereunder to such shares of capital stock (but taking into account
the relative value of the shares of Common Stock pursuant to such Fundamental Transaction and the value of such shares of capital
stock, such number of shares of capital stock and such exercise price being for the purpose of protecting the economic value of
this Warrant immediately prior to the consummation of such Fundamental Transaction), and which is reasonably satisfactory in form
and substance to the Holder. Upon the occurrence of any such Fundamental Transaction, the Successor Entity shall succeed to, and
be substituted for (so that from and after the date of such Fundamental Transaction, the provisions of this Warrant and the other
Transaction Documents referring to the “Company” shall refer instead to the Successor Entity), and may exercise every
right and power of the Company and shall assume all of the obligations of the Company under this Warrant and the other Transaction
Documents with the same effect as if such Successor Entity had been named as the Company herein.







 




    	9



    	 



    




 


f)
Calculations. All calculations under this Section 3 shall be made to the nearest cent or the nearest 1/100th of a share,
as the case may be. For purposes of this Section 3, the number of shares of Common Stock deemed to be issued and outstanding as
of a given date shall be the sum of the number of shares of Common Stock (excluding treasury shares, if any) issued and outstanding.


 


g)
Notice to Holder.


 


i.
Adjustment to Exercise Price. Whenever the Exercise Price is adjusted pursuant to any provision of this Section 3, the
Company shall promptly deliver to the Holder by facsimile or email a notice setting forth the Exercise Price after such adjustment
and any resulting adjustment to the number of Warrant Shares and setting forth a brief statement of the facts requiring such adjustment.


 


ii.
Notice to Allow Exercise by Holder. If (A) the Company shall declare a dividend (or any other distribution in whatever
form) on the Common Stock, (B) the Company shall declare a special nonrecurring cash dividend on or a redemption of the Common
Stock, (C) the Company shall authorize the granting to all holders of the Common Stock rights or warrants to subscribe for or
purchase any shares of capital stock of any class or of any rights, (D) the approval of any stockholders of the Company shall
be required in connection with any reclassification of the Common Stock, any consolidation or merger to which the Company is a
party, any sale or transfer of all or substantially all of the assets of the Company, or any compulsory share exchange whereby
the Common Stock is converted into other securities, cash or property, or (E) the Company shall authorize the voluntary or involuntary
dissolution, liquidation or winding up of the affairs of the Company, then, in each case, the Company shall cause to be delivered
by facsimile or email to the Holder at its last facsimile number or email address as it shall appear upon the Warrant Register
of the Company, at least 20 calendar days prior to the applicable record or effective date hereinafter specified, a notice stating
(x) the date on which a record is to be taken for the purpose of such dividend, distribution, redemption, rights or warrants,
or if a record is not to be taken, the date as of which the holders of the Common Stock of record to be entitled to such dividend,
distributions, redemption, rights or warrants are to be determined or (y) the date on which such reclassification, consolidation,
merger, sale, transfer or share exchange is expected to become effective or close, and the date as of which it is expected that
holders of the Common Stock of record shall be entitled to exchange their shares of the Common Stock for securities, cash or other
property deliverable upon such reclassification, consolidation, merger, sale, transfer or share exchange; provided that the failure
to deliver such notice or any defect therein or in the delivery thereof shall not affect the validity of the corporate action
required to be specified in such notice. To the extent that any notice provided in this Warrant constitutes, or contains, material,
non-public information regarding the Company or any of the Subsidiaries, the Company shall simultaneously file such notice with
the Commission pursuant to a Current Report on Form 8-K. The Holder shall remain entitled to exercise this Warrant during the
period commencing on the date of such notice to the effective date of the event triggering such notice except as may otherwise
be expressly set forth herein.


 




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Section
4. Transfer of Warrant.


 


a)
Transferability. Subject to compliance with any applicable securities laws and the conditions set forth in Section 4(d)
hereof and to the provisions of Section 4.1 of the Purchase Agreement, this Warrant and all rights hereunder are transferable,
in whole or in part, upon surrender of this Warrant at the principal office of the Company or its designated agent, together with
a written assignment of this Warrant substantially in the form attached hereto duly executed by the Holder or its agent or attorney
and funds sufficient to pay any transfer taxes payable upon the making of such transfer. Upon such surrender and, if required,
such payment, the Company shall execute and deliver a new Warrant or Warrants in the name of the assignee or assignees, as applicable,
and in the denomination or denominations specified in such instrument of assignment, and shall issue to the assignor a new Warrant
evidencing the portion of this Warrant not so assigned, and this Warrant shall promptly be cancelled. Notwithstanding anything
herein to the contrary, the Holder shall not be required to physically surrender this Warrant to the Company unless the Holder
has assigned this Warrant in full, in which case, the Holder shall surrender this Warrant to the Company within three (3) Trading
Days of the date the Holder delivers an assignment form to the Company assigning this Warrant full. The Warrant, if properly assigned
in accordance herewith, may be exercised by a new holder for the purchase of Warrant Shares without having a new Warrant issued.


 


b)
New Warrants. This Warrant may be divided or combined with other Warrants upon presentation hereof at the aforesaid office
of the Company, together with a written notice specifying the names and denominations in which new Warrants are to be issued,
signed by the Holder or its agent or attorney. Subject to compliance with Section 4(a), as to any transfer which may be involved
in such division or combination, the Company shall execute and deliver a new Warrant or Warrants in exchange for the Warrant or
Warrants to be divided or combined in accordance with such notice. All Warrants issued on transfers or exchanges shall be dated
the original Issue Date and shall be identical with this Warrant except as to the number of Warrant Shares issuable pursuant thereto.


 


c)
Warrant Register. The Company shall register this Warrant, upon records to be maintained by the Company for that purpose
(the “Warrant Register”), in the name of the record Holder hereof from time to time. The Company may deem and
treat the registered Holder of this Warrant as the absolute owner hereof for the purpose of any exercise hereof or any distribution
to the Holder, and for all other purposes, absent actual notice to the contrary.


 


d)
Transfer Restrictions. If, at the time of the surrender of this Warrant in connection with any transfer of this Warrant,
the transfer of this Warrant shall not be either (i) registered pursuant to an effective registration statement under the Securities
Act and under applicable state securities or blue sky laws or (ii) eligible for resale without volume or manner-of-sale restrictions
or current public information requirements pursuant to Rule 144, the Company may require, as a condition of allowing such transfer,
that the Holder or transferee of this Warrant, as the case may be, comply with the transfer restrictions provided by the Purchase
Agreement, including those set forth in Section 5.7 thereof.


 




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e)
Representation by the Holder. The Holder, by the acceptance hereof, represents and warrants that (i) it is acquiring this
Warrant and, upon any exercise hereof, will acquire the Warrant Shares issuable upon such exercise, for its own account and not
with a view to or for distributing or reselling such Warrant Shares or any part thereof in violation of the Securities Act or
any applicable state securities law, except pursuant to sales registered or exempted under the Securities Act; and (ii) it is
an “accredited investor” as defined in Regulation D promulgated under the Securities Act of 1933, as amended.


 


Section
5. Miscellaneous.


 


a)
No Rights as Stockholder Until Exercise. This Warrant does not entitle the Holder to any voting rights, dividends or other
rights as a stockholder of the Company prior to the exercise hereof as set forth in Section 2(d)(i), except as expressly set forth
in Section 3.


 


b)
Loss, Theft, Destruction or Mutilation of Warrant. The Company covenants that upon receipt by the Company of evidence reasonably
satisfactory to it of the loss, theft, destruction or mutilation of this Warrant or any stock certificate relating to the Warrant
Shares, and in case of loss, theft or destruction, of indemnity or security reasonably satisfactory to it (which, in the case
of the Warrant, shall not include the posting of any bond), and upon surrender and cancellation of such Warrant or stock certificate,
if mutilated, the Company will make and deliver a new Warrant or stock certificate of like tenor and dated as of such cancellation,
in lieu of such Warrant or stock certificate.


 


c)
Saturdays, Sundays, Holidays, etc. If the last or appointed day for the taking of any action or the expiration of any right
required or granted herein shall not be a Business Day, then, such action may be taken or such right may be exercised on the next
succeeding Business Day.


 


d)
Authorized Shares.


 


The
Company covenants that, during the period the Warrant is outstanding, it will reserve from its authorized and unissued Common
Stock a sufficient number of shares to provide for the issuance of the Warrant Shares upon the exercise of any purchase rights
under this Warrant. The Company further covenants that its issuance of this Warrant shall constitute full authority to its officers
who are charged with the duty of issuing the necessary Warrant Shares upon the exercise of the purchase rights under this Warrant.
The Company will take all such reasonable action as may be necessary to assure that such Warrant Shares may be issued as provided
herein without violation of any applicable law or regulation, or of any requirements of the Trading Market upon which the Common
Stock may be listed. The Company covenants that all Warrant Shares which may be issued upon the exercise of the purchase rights
represented by this Warrant will, upon exercise of the purchase rights represented by this Warrant and payment for such Warrant
Shares in accordance herewith, be duly authorized, validly issued, fully paid and nonassessable and free from all taxes, liens
and charges created by the Company in respect of the issue thereof (other than taxes in respect of any transfer occurring contemporaneously
with such issue).


 




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Except
and to the extent as waived or consented to by the Holder, the Company shall not by any action, including, without limitation,
amending its certificate of incorporation or through any reorganization, transfer of assets, consolidation, merger, dissolution,
issue or sale of securities or any other voluntary action, avoid or seek to avoid the observance or performance of any of the
terms of this Warrant, but will at all times in good faith assist in the carrying out of all such terms and in the taking of all
such actions as may be necessary or appropriate to protect the rights of Holder as set forth in this Warrant against impairment.
Without limiting the generality of the foregoing, the Company will (i) not increase the par value of any Warrant Shares above
the amount payable therefor upon such exercise immediately prior to such increase in par value, (ii) take all such action as may
be necessary or appropriate in order that the Company may validly and legally issue fully paid and nonassessable Warrant Shares
upon the exercise of this Warrant and (iii) use commercially reasonable efforts to obtain all such authorizations, exemptions
or consents from any public regulatory body having jurisdiction thereof, as may be, necessary to enable the Company to perform
its obligations under this Warrant.


 


Before
taking any action which would result in an adjustment in the number of Warrant Shares for which this Warrant is exercisable or
in the Exercise Price, the Company shall obtain all such authorizations or exemptions thereof, or consents thereto, as may be
necessary from any public regulatory body or bodies having jurisdiction thereof.


 


e)
Jurisdiction. All questions concerning the construction, validity, enforcement and interpretation of this Warrant shall
be determined in accordance with the provisions of the Purchase Agreement.


 


f)
Restrictions. The Holder acknowledges that the Warrant Shares acquired upon the exercise of this Warrant, if not registered
and the Holder does not utilize cashless exercise, will have restrictions upon resale imposed by state and federal securities
laws.


 


g)
Nonwaiver and Expenses. No course of dealing or any delay or failure to exercise any right hereunder on the part of Holder
shall operate as a waiver of such right or otherwise prejudice the Holder’s rights, powers or remedies, notwithstanding
the fact that all rights hereunder terminate on the Termination Date. If the Company willfully and knowingly fails to comply with
any provision of this Warrant, which results in any material damages to the Holder, the Company shall pay to the Holder such amounts
as shall be sufficient to cover any costs and expenses including, but not limited to, reasonable attorneys’ fees, including
those of appellate proceedings, incurred by the Holder in collecting any amounts due pursuant hereto or in otherwise enforcing
any of its rights, powers or remedies hereunder.


 




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h)
Notices. Any notice, request or other document required or permitted to be given or delivered to the Holder by the Company
shall be delivered in accordance with the notice provisions of the Purchase Agreement.


 


i)
Limitation of Liability. No provision hereof, in the absence of any affirmative action by the Holder to exercise this Warrant
to purchase Warrant Shares, and no enumeration herein of the rights or privileges of the Holder, shall give rise to any liability
of the Holder for the purchase price of any Common Stock or as a stockholder of the Company, whether such liability is asserted
by the Company or by creditors of the Company.


 


j)
Remedies. The Holder, in addition to being entitled to exercise all rights granted by law, including recovery of damages,
will be entitled to specific performance of its rights under this Warrant. The Company agrees that monetary damages would not
be adequate compensation for any loss incurred by reason of a breach by it of the provisions of this Warrant and hereby agrees
to waive and not to assert the defense in any action for specific performance that a remedy at law would be adequate.


 


k)
Successors and Assigns. Subject to applicable securities laws, this Warrant and the rights and obligations evidenced hereby
shall inure to the benefit of and be binding upon the successors and permitted assigns of the Company and the successors and permitted
assigns of Holder. The provisions of this Warrant are intended to be for the benefit of any Holder from time to time of this Warrant
and shall be enforceable by the Holder or holder of Warrant Shares.


 


l)
Amendment. This Warrant may be modified or amended or the provisions hereof waived with the written consent of the Company
and the Holder.


 


m)
Severability. Wherever possible, each provision of this Warrant shall be interpreted in such manner as to be effective
and valid under applicable law, but if any provision of this Warrant shall be prohibited by or invalid under applicable law, such
provision shall be ineffective to the extent of such prohibition or invalidity, without invalidating the remainder of such provisions
or the remaining provisions of this Warrant.


 


n)
Headings. The headings used in this Warrant are for the convenience of reference only and shall not, for any purpose, be
deemed a part of this Warrant.


 


********************


 


(Signature
Page Follows)


 




    	14



    	 



    

 


IN
WITNESS WHEREOF, the Company has caused this Class B Warrant to be executed by its officer thereunto duly authorized as of the
date first above indicated.


 


	 	hemispherx
                                         biopharma, inc.






	 	 
	 	By:	            
	 	Name:	 
	 	Title:	 
	 	 	 


 







    	15



    	 



    




 


NOTICE
OF EXERCISE


 


To:
hemispherx biopharma, inc.


 


(1)
The undersigned hereby elects to purchase ________ Warrant Shares of the Company pursuant to the terms of the attached Class B
Warrant (only if exercised in full), and tenders herewith payment of the exercise price in full, together with all applicable
transfer taxes, if any.


 


(2)
Payment shall take the form of (check applicable box):


 


[  ] in lawful money of the United States; or


 


[  ] [if permitted the cancellation of such number of Warrant Shares as is necessary, in accordance with the formula set forth in
subsection 2(c), to exercise this Class B Warrant with respect to the maximum number of Warrant Shares purchasable pursuant to
the cashless exercise procedure set forth in subsection 2(c).


 


(3)
Please issue said Warrant Shares in the name of the undersigned or in such other name as is specified below:


_______________________________


 





The
Warrant Shares shall be delivered to the following DWAC Account Number:


 


_______________________________


 


_______________________________


 


_______________________________


 


(4)
Accredited Investor. The undersigned is an “accredited investor” as defined in Regulation D promulgated under
the Securities Act of 1933, as amended.


 


[SIGNATURE
OF HOLDER]


 


Name
of Investing Entity: ___________________________________________________________________________


 


Signature
of Authorized Signatory of Investing Entity: _____________________________________________________


 


Name
of Authorized Signatory: _______________________________________________________________________


 


Title
of Authorized Signatory: ________________________________________________________________________


 


Date:
___________________________________________________________________________________________


 




    	 	 	 



     


    

 


EXHIBIT
B


 


ASSIGNMENT
FORM


 


(To
assign the foregoing Class B Warrant, execute this form and supply required information. Do not use this form to purchase shares.)


 


FOR
VALUE RECEIVED, the foregoing Class B Warrant and all rights evidenced thereby are hereby assigned to


 


	Name:	 
	 	(Please
    Print)
	 	 
	Address:	 
	 	(Please
    Print)
	 	 
	Phone
    Number:	 
	 	 
	Email
    Address:	 
	 	 
	Dated:
    ____________ ____, __________ 	 
	 	 
	Holder’s
    Signature:_____________________	 
	 	 
	Holder’s
    Address:______________________