Exhibit 10.33


 


PROMISSORY NOTE


 


	$75,000.00	West Chester, Pennsylvania


January 7, 2021


 


For value received,
the undersigned, Virpax Pharmaceuticals, Inc., a Delaware corporation, (herein called “Maker”), promises to pay to
the order of Anthony P. Mack (herein, together with its successors and assigns who become holders of this Promissory Note (the
“Note”), called “Holder”) at the address set forth on the signature page hereof, or such other place as
Holder may designate in writing, the principal sum of $75,000.00 together with simple interest on the unpaid principal amount from
time to time owing hereunder, commencing on the above date, at the rate of 1.35% per annum.


 


Interest and principal
payments on this Note shall be payable as follows:


 


Interest shall accrue
on this Note and not be payable until the maturity date described below (or repayment of the Note). All principal and accrued and
unpaid interest under this Note shall be payable on January 6, 2022 (the “Maturity Date”), when the entire principal
balance and any accrued interest on this Note shall be due and payable. Maker shall pay all of Holder’s costs, expenses,
and attorneys’ fees incurred in connection with the collection or enforcement of this Note.


 


All payments required
hereunder shall be calculated on the basis of a 360-day year, divided into twelve 30-day months.


 


This Note may be prepaid
in whole or in part at any time without penalty or bonus.


 


Both principal and
interest shall be paid by Maker in lawful money of the United States of America. This Note has been executed under and shall be
construed and enforced in accordance with the laws of the State of New York from time to time in effect, except to the extent that
the United States federal laws preempt or otherwise control the laws of the State of New York, including without limitation the
extent to which the United States federal law permits Holder to contract for, charge or receive a greater amount of interest than
do the laws of the State of New York. This Note is unsecured.


 


No delay or omission
on the part of Holder hereof in exercising any right hereunder shall operate as a waiver of such right or of any other right under
this Note.


 


Neither this Note nor
any term hereof may be waived, amended, discharged, modified, changed, or terminated orally, nor shall any waiver of any provision
hereof be effective except by an instrument in writing signed by Maker and Holder thereof.


 


Whenever used herein,
the words “Maker” and “Holder” shall be deemed to include their respective heirs, personal representatives,
successors and assigns.


 


All notices to be given
under this Note shall be deemed served upon receipt by the addressee or, if mailed, upon the expiration of twenty-four (24) hours
after deposit in the United States Postal Service, certified mail, postage prepaid, addressed to the address of Maker or Holder
as set forth in the books and records of Virpax Pharmaceuticals, Inc.


 


[REST OF PAGE
INTENTIONALLY LEFT BLANK]


 




     


     


    

 


	Signed on January 7, 2021.	 
	 	 
	MAKER	 
	 	 
	/s/ Jeffrey Gudin	 
	 	 
	Virpax Pharmaceuticals, Inc.	 
	 	 
	By: Jeffrey Gudin	 
	 	 
	EVP, Chief Medical Officer	 
	 	 
	HOLDER	 
	 	 
	/s/ Anthony P. Mack	 
	 	 
	Anthony P. Mack	 


 


[Signature
page to Unsecured Promissory Note]