THIS NOTE HAS NOT BEEN REGISTERED UNDER
THE SECURITIES ACT OF 1933, AS AMENDED, OR ANY STATE SECURITIES LAWS, AND MAY NOT BE TRANSFERRED UNLESS THE COMPANY HAS RECEIVED
A WRITTEN OPINION FROM COUNSEL IN FORM AND SUBSTANCE SATISFACTORY TO THE COMPANY STATING THAT SUCH TRANSFER IS BEING MADE IN COMPLIANCE
WITH ALL APPLICABLE FEDERAL AND STATE SECURITIES LAWS.


 


FOURTH AMENDED AND RESTATED 


PROMISSORY NOTE


 


	Frederick, Maryland	$1,800,000.00
	May 31, 2013	Due: July 31, 2013


 


For value received,
the undersigned, Vaccinogen, Inc., a Maryland corporation (“Maker”), promises to pay to the order of
The Abell Foundation, Inc., a Maryland corporation (“Payee”), at such place as the holder of this Note
may from time to time designate the principal sum of One Million Eight Hundred Thousand Dollars ($1,800,000.00), together with
the interest thereon at the rate hereinafter specified and any and all other sums which may be due and owing to the holder of
this Note in accordance with the following terms:


 


1.          Note
Issuance. This non-negotiable promissory note (this “Note”) is issued pursuant to the Note and Warrant
Purchase Agreement dated as of October 26, 2011, between Maker and Payee, as amended by that certain Amendment No. 1 to Note and
Warrant Purchase Agreement February 16, 2012, between Maker and Payee, as further amended by that certain Amendment No. 2 to Note
and Warrant Purchase Agreement dated January 16, 2013, by and between Maker and Payee, as further amended by that certain Amendment
No. 3 to Note and Warrant Purchase Agreement dated April 18, 2013, by and between Maker and Payee, and as further amended by that
certain Amendment No. 4 to Note and Warrant Purchase Agreement dated as of the date hereof by and between Maker and Payee (as
amended, and as the same may be further amended, supplemented or otherwise modified from time to time, the “Note and
Warrant Purchase Agreement”), and Payee is subject to the terms and entitled to the benefits of this Note and the
Note and Warrant Purchase Agreement and may enforce the agreements of Maker contained herein and therein and exercise the remedies
provided for hereby and thereby or otherwise available in respect hereto and thereto. Capitalized terms used herein without definition
have the meaning assigned thereto in the Note and Warrant Purchase Agreement.


 


2.          Payment;
Interest Rate. Subject to the further provisions of this Section 2 and of Section 4, the principal amount under this
Note shall be due and payable on July 31, 2013 (the “Maturity Date”). Simple interest shall accrue
from and after the date of this Note on the principal amount outstanding from time to time at a rate of eight percent (8%)
per annum and, together with all accrued interest under the Existing Note (as hereinafter defined), shall be due and payable
on the Maturity Date. Notwithstanding the foregoing, to the extent necessary to repay the principal amount of this Note in
full and all accrued interest thereon, this Note shall be paid concurrently with the closing of each issuance or sale of
additional shares of capital stock, or securities directly or indirectly convertible or exchangeable for capital stock, of
the Company (each an “Equity Issuance”) occurring after May 28, 2013 in an amount equal to (a) twenty
percent (20%) of the next $3,778,771 of gross proceeds of such Equity Issuance(s), (b) twenty-five percent (25%) of the next
$6,000,000 of gross proceeds of such Equity Issuance(s), and (c) one hundred percent (100%) of the net proceeds of all Equity
Issuance(s) thereafter.


 




    	 



    	 



    

 


3.          Calculation
of Interest. Interest on this Note shall be calculated on the basis of a 360 day per year factor applied to the actual days
on which there exists an unpaid principal balance due under this Note.


 


4.          Application
of Payments. All payments made hereunder shall be applied first to late penalties, costs of collection or other sums owing
the holder, then to accrued interest (including accrued interest under the Existing Note) and last to payment of the principal
amount of this Note.


 


5.          Prepayment.
Maker may prepay this Note in whole or in part at any time or from time to time without penalty or additional interest, provided
that payments are applied as provided in Section 4 above. Amounts repaid hereunder may not be reborrowed.


 


6.          Use
of Proceeds. The purpose of this Note is to fund the working capital needs of Maker, and, by its execution and delivery of
this Note, Maker covenants and agrees that the proceeds of this Note shall be used solely for such purpose. Without limitation
of the foregoing, no proceeds of this Note will be used to purchase or carry any margin stock (within the meaning of Regulation
U issued by the Board of Governors of the Federal Reserve System) or to extend credit to others for the purpose of purchasing or
carrying any margin stock.


 


7.          Events
of Default. The occurrence of any one or more of the following events (the “Events of Default”)
shall constitute an Event of Default hereunder:


 


(a)          any
failure by Maker to pay any principal, interest or other amount due under this Note at or prior to the time when it is due and
payable;


 


(b)          any
failure of Maker to duly perform, comply with or observe any of the other terms, conditions or covenants contained in this Note
or in any of the other Transaction Documents, if such failure remains uncured for a period of five (5) business days after written
notice of such failure is delivered by Payee;


 


(c)          any
representation or warranty made by Maker herein or in any of the other Transaction Documents or in connection therewith, or any
information provided by or on behalf of Maker pursuant hereto or pursuant to any of the other Transaction Documents or in connection
therewith, being or becoming false, misleading, incomplete or incorrect in any material respect;


 




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(d)          Maker
(i) defaults in any payment of principal of or interest on any of its Debt (as defined below) (other than this Note), beyond the
period of grace, if any, provided in the instrument or promissory note under which such Debt was created; or (ii) defaults in the
observance or performance of any other agreement or condition relating to any such Debt or contained in any instrument or agreement
relating thereto, or any other event occurs or condition exists, the effect of which default or other event or condition is to
cause, or to permit the holder(s) of such Debt to cause, with the giving of notice if required, such Debt to become due prior to
its stated maturity;


 


(e)          any
judgment against Maker or any attachment or levy against the property of Maker with respect to a claim remains unpaid, unstayed,
on appeal, undischarged, unbonded or undismissed for a period of thirty (30) days;


 


(f)          Maker
generally does not pay its debts as such debts become due, or admits in writing its inability to pay its debts generally; or a
petition for relief in a bankruptcy court is filed by Maker; or Maker applies for, consents to or acquiesces in the appointment
of a trustee, custodian or receiver for Maker or any of its assets or property or makes a general assignment for the benefit of
its creditors or, in the absence of such application, consent or acquiescence, a trustee, custodian or receiver is appointed for
Maker or for a substantial part of its assets or property and is not discharged within thirty (30) days hereafter; or any bankruptcy,
reorganization, debt arrangement or other proceeding or case under any bankruptcy or insolvency law or any dissolution or liquidation
proceeding is instituted against Maker and if instituted against Maker is consented to or acquiesced in by Maker or remains undismissed
for sixty (60) days thereafter; or Maker takes any action to authorize any of the actions described in this subsection; or


 


(g)          any
demand by a holder of any of the Current Payables (as defined below) to make payment in excess of $30,000 on any Current Payable
which remains unsatisfied by Maker for a period of ten (10) days.


 


“Debt” of any
person means, without duplication, (a) all indebtedness of such person for borrowed money, (b) all obligations of such person to
pay the deferred purchase price of property or services, except trade accounts payable arising in the ordinary course of business,
(c) all obligations of such person evidenced by notes, bonds, debentures or other similar instruments, (d) all
obligations of such person created or arising under any conditional sale or other title retention agreement or arrangement with
respect to property acquired by such person, (e) all obligations of such person as lessee under leases that have been or should
be, in accordance with generally accepted accounting principles, recorded as capital leases, (f) all obligations, contingent or
otherwise, of such person in respect of acceptances, letters of credit or similar extensions of credit, (g) all Debt of others
guaranteed directly or indirectly in any manner by such person, and (h) all Debt of others secured by a lien or other encumbrance
on any asset of such person, whether or not such person has assumed or become liable for the payment of such Debt. Notwithstanding
the foregoing, the term “Debt” shall not include payables of the Maker which are outstanding prior to
the date of this Note (whether or not past due) (the “Current Payables”) including, but not limited
to, the amounts owing to Organon Teknika Corporation and Organon BioSciences International B.V. (and their successors) pursuant
to that certain letter agreement dated October 31, 2007.


 




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8.          Default
Interest Rate. Upon the occurrence of an Event of Default until this Note is paid in full, the interest rate applicable to
the then outstanding balance shall be increased to ten percent (10%) upon written notice to Maker by Payee of such Event of Default.


 


9.          Rights
and Remedies. If any one or more Events of Default shall occur, then in each and every such case, Payee at its option may at
any time thereafter exercise and/or enforce any or all of the following rights and remedies:


 


(a)          declare
upon notice to Maker all of the amounts payable hereunder to be immediately due and payable, whereupon same shall become due and
payable, together with accrued and unpaid interest thereon and all other sums due hereunder, immediately without presentment, demand
or protest, all of which Maker hereby waives, provided that upon the occurrence of an Event of Default described in Section 7(f),
all amounts shall automatically be and become due and payable immediately without any declaration; and


 


(b)          bring
suit for payment and exercise any other rights and remedies available to Payee pursuant to this Note, any of the other Transaction
Documents or applicable law.


 


CONFESSION OF JUDGMENT. IF THIS NOTE IS
NOT PAID WHEN DUE, MAKER HEREBY IRREVOCABLY AUTHORIZES AND EMPOWERS PAYEE, BY ITS ATTORNEY, OR BY THE PRONOTHARY OR CLERK OF ANY
COURT OF RECORD IN THE STATE OF MARYLAND OR IN ANY JURISDICTION WHERE PERMITTED BY LAW TO BE MAKER’S TRUE AND LAWFUL ATTORNEY-IN-FACT,
AND IN MAKER’S NAME AND STEAD, TO APPEAR FOR MAKER AND CONFESS AND ENTER JUDGMENT AGAINST IT IN FAVOR OF PAYEE IN ANY JURISDICTION
IN WHICH MAKER OR ANY OF ITS PROPERTY IS LOCATED FOR: (i) THE ENTIRE UNPAID PRINCIPAL AMOUNT OF THIS NOTE THEN REMAINING UNPAID,
(ii) INTEREST THEREON THEN ACCRUED AND UNPAID, (iii) ATTORNEYS’ FEES IN THE AMOUNT OF $10,000, AND (iv) COURT COSTS, WITH
OR WITHOUT DECLARATION, WITHOUT STAY OF EXECUTION AND WITH RELEASE OF ALL ERRORS AND THE RIGHT TO ISSUE EXECUTION FORTHWITH, AND
FOR DOING SO THIS NOTE OR A COPY VERIFIED BY AFFIDAVIT SHALL BE A SUFFICIENT WARRANT. MAKER HEREBY WAIVES AND RELEASES ALL RELIEF
FROM ANY AND ALL APPRAISEMENT, STAY OR EXEMPTION LAW OF ANY STATE NOW IN FORCE OR HEREAFTER ENACTED. THIS AUTHORITY AND POWER SHALL
NOT BE EXHAUSTED BY THE EXERCISE THEREOF, AND SHALL CONTINUE UNTIL THE OBLIGATIONS ARE FULLY PAID, PERFORMED, DISCHARGED AND SATISFIED.
IT IS THE INTENTION OF THE PARTIES HERETO THAT THE PROVISONS OF THIS NOTE RELATING TO THE PAYMENT OF ATTORNEYS FEES SHALL NOT MERGE
INTO ANY JUDGMENT ENTERED IN CONNECTION HEREWITH, AND PAYEE SHALL RETAIN THE RIGHT TO RECOVER FROM MAKER FEES INCURRED IN THE COLLECTION
HEREOF WHICH ARE INCURRED AFTER THE ENTRY OF FINAL JUDGMENT ON THIS NOTE. Notwithstanding the amount of attorneys’ fees for
which judgment may be confessed hereunder, by its acceptance hereof Payee agrees to use reasonable efforts to retain counsel who
will charge Payee only for time and expenses at standard hourly rates, and Payee will not enforce the attorney’s fee portion
of any confessed judgment for an amount in excess of the actual fees and expenses charged to Payee by its counsel in connection
with confessing judgment against Maker and collecting on such judgment. (This provision shall not limit the obligation of Maker
to pay all reasonable attorneys’ fees incurred by Payee in connection with this Note.)


 




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Each right, power and
remedy of Payee specified herein or available at law or in equity or by statute shall be cumulative and concurrent and shall be
in addition to every other right, power or remedy provided for in this Note or available at law or in equity and the exercise or
beginning of the exercise by Payee of any one or more of such rights, powers or remedies shall not preclude the simultaneous or
later exercise by Payee of any or all other rights, powers or remedies.


 


10.         Costs
of Collection. If at any time the indebtedness evidenced by this Note is collected through legal proceedings or this Note is
placed in the hands of an attorney or attorneys for collection, Maker hereby agrees to pay all costs and expenses (including attorneys’
fees) incurred by the holder of this Note in enforcing its rights and collecting or attempting to collect all amounts due hereunder
and under any related documents.


 


11.         Extensions
or Modifications. Maker agrees that the maturity of this Note or any payment due hereunder may be extended by Payee at any
time or from time to time, this Note may be modified by Payee, and any defaults hereunder may be waived by Payee without releasing,
discharging or affecting the liability of Maker. No modification or waiver of any provision of this Note, and no consent by Payee
to any failure of Maker to comply with any provision of this Note, shall in any event be effective unless the same shall be in
writing signed by Payee.


 


12.         Choice
of Law; Jurisdiction; Severability. This Note shall be governed, construed and enforced in strict accordance with the laws
of the State of Maryland, without reference to principles of conflict of laws. Maker agrees that any suit, action or proceeding
instituted by Payee with respect to any of the obligations of Maker hereunder may be brought in any State or federal court located
in the State of Maryland (in addition to such other courts in which jurisdiction and venue may be appropriate), and Maker consents
to the in personam jurisdiction of such courts. If any provision of this Note shall for any reason be invalid or
unenforceable, such invalidity or unenforceability shall not affect any other provision.


 


13.         Waiver
of Defenses. In the event the holder of this Note transfers this Note for value, Maker agrees that none of such subsequent
holders of this Note shall be subject to any claims or defenses which Maker may have against the prior holder, all of which are
waived as to the subsequent holders and all subsequent holders shall have the rights of a holder in due course with respect to
Maker even though the subsequent holder might not qualify under applicable law absent this paragraph as a holder in due course.


 




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14.         Waivers.
Maker hereby waives (a) presentment, protest and demand and notice of protest, demand, dishonor and nonpayment of this Note; (b)
all claims and causes of action of Maker against Payee for punitive, exemplary or other non-compensatory damages; and (c) diligence
in the enforcement or collection of all of the obligations of Maker hereunder. EACH OF PAYEE AND MAKER AGREES THAT ANY ACTION,
SUIT OR PROCEEDING INVOLVING ANY CLAIM, COUNTERCLAIM OR CROSS-CLAIM ARISING OUT OF OR IN ANY WAY RELATING, DIRECTLY OR INDIRECTLY,
TO ANY OF THE OBLIGATIONS OF MAKER HEREUNDER SHALL BE TRIED BY A COURT AND NOT BY A JURY, EACH OF PAYEE AND MAKER HEREBY WAIVING
ANY RIGHT TO TRIAL BY JURY IN ANY SUCH ACTION, SUIT OR PROCEEDING AND HEREBY AGREEING THAT THIS WAIVER OF TRIAL BY JURY IS A MATERIAL
ASPECT OF THEIR AGREEMENTS.


 


15.         No
Waiver; No assignment. The delay or failure of any holder to exercise its rights hereunder shall not be deemed a waiver thereof.
No waiver of any rights of holder shall be effective unless in writing and signed by the holder and any waiver of any right shall
not apply to any other right or to such right in any subsequent event or circumstance not specifically included in such waiver.
Maker may not assign its rights or obligations under this Note.


 


16.         Headings.
The headings used in this Note are used for convenience only and are not to be considered in construing or interpreting this Note.


 


17.         Replacement
Note. This Note is given pursuant to the terms of that certain Amendment No. 4 to Note and Warrant Purchase Agreement of even
date herewith by and between Maker and Payee in replacement of the “Note” as defined in the Note and Warrant Purchase
Agreement immediately prior to the date hereof (the “Existing Note”). The execution of this Note and
the replacement of the Existing Note hereby shall not constitute or act as a novation, satisfaction or extinguishment of the indebtedness
evidenced by the Existing Note, and all accrued and unpaid interest under the Existing Note shall be due and payable on the Maturity
Date unless required to be paid prior thereto pursuant to the terms hereof. This Note shall for all purposes be the “Note”
as defined in the Note and Warrant Purchase Agreement and in that certain Security Agreement dated October 26, 2011, by
and between Maker and Payee (the “Security Agreement”), the terms of which are incorporated herein and made a part
hereof as if fully set forth herein. This Note is one of the “Transaction Documents” as defined in the Note and Warrant
Purchase Agreement, and the obligations of Maker hereunder are part of the “Obligations” as defined in the Security
Agreement.


 


[THE NEXT PAGE IS THE SIGNATURE PAGE]


 




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IN WITNESS WHEREOF, Maker has caused
this Note to be executed on its behalf by its duly authorized officer as of the day and year first above written.


 


	 	VACCINOGEN, INC.
	 	 	 
	 	By: 	/s/ Michael
G. Hanna, Jr.
	 	Name:	Michael G. Hanna, Jr., Ph.D.
	 	Title:	Chairman and Chief Executive Officer
	 	 	 
	 	By:	/s/ Andrew L. Tussing
	 	Name: 	Andrew L. Tussing
	 	Title:	President and Chief Operating Officer


 




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