Exhibit 10.35


 


NLS Pharmaceutics Ltd.


Alter Postplatz 2


CH-6370 Stans


 


8
January 2021


 


Addendum
Number 4 to Convertible Promissory Note (“Addendum”)


 


Magnetic
Rock Investment AG, a Swiss stock corporation with its registered office at ________________, Switzerland, and company no.
CHE-184.662.704 (the “Lender”), granted to NLS Pharmaceutics Ltd. (formerly NLS-1 Pharma AG), a Swiss
stock corporation with its registered office at Alter Postplatz 2, 6370 Stans, Switzerland, and company no. CHE-447.067.367 (the
“Borrower”), based on the promissory note dated 18 January 2019, as amended on 16 September 2019, in January
2020 and on 3 October 2020 (the “Promissory Note”) the principal sum of CHF 550,000.00 (the “Principal
Amount”), together with interest at 10.0% p.a. (the “Interest”) thereon accruing on and from the
date of payment until the entire Principal Amount is repaid (the Interest and the Principal Amount hereinafter jointly referred
to as the “Loan”). The Interest shall be calculated based on the exact number of days in relation to a year
of 360 days (actual/360), compounded annually.


 


For
the sake of clarity, CHF 500,000.00 of the Principle Amount (“Payment A”) was paid to the Borrower on 31 August
2018 (the “Date of Payment A”) and CHF 50,000.00 of the Principle Amount (“Payment B”) was
paid to the Borrower on 18 December 2018 (the “Date of Payment B”).


 


On
12 March 2019 CHF 526,979.84 of the Principal Amount was settled by conversion into equity (the “Conversion Amount”),
whereas the Lender received eight (8) registered shares at an issue price of CHF 65,872.48 (the “Conversion”).
The Conversion Amount consists of the full amount of Payment B and of CHF 476,979.84 from Payment A. As a result of the Conversion,
an outstanding amount of CHF 23,020.16 with regard to Payment A (the “Open Amount Payment A”) remains open.


 


The
following is a statement of the amended terms and conditions of the Promissory Note:


 


	1
        – Extension Maturity Date

         
	 	According
        to section 2 of the Promissory Note, the Maturity Date and therefore the repayment of the Loan was agreed to take place
        no later than 31 December 2020.

         

        According
        to section 2 of the Promissory Note, the Lender may unilaterally extend the repayment term and set a new Maturity Date.

         

        The
Lender hereby extends the Maturity Date of the Loan, replacing the existing Maturity Date, until 31 March 2021 and, thus, the
Loan shall be due for repayment no later than 31 March 2021. The Borrower hereby acknowledges and agrees with the extension. References
to the Maturity Date in the Promissory Note shall be to 31 March 2021.

	 	 	 
	2
    - Governing Law	 	This
Addendum shall be governed by and construed in accordance with the substantive laws of Switzerland, without reference to principles
of conflict of laws or choice of laws.

	 	 	 
	3
    – Jurisdiction	 	All
disputes arising out of or in connection with this Addendum, including disputes regarding its conclusion, validity, binding effect,
amendment, breach, termination or rescission shall be subject to the exclusive jurisdiction of the ordinary courts of Stans (NW). 



 


 


[signature
page to follow]


 






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The
Lender


Magnetic
Rock Investment


 


	/s/
    Ronald Hafner	 	 
	Ronald
    Hafner	 	 
	Chairman
    of the Board of Directors	 	 
	 	 	 
	 	 	 
	The
    Borrower	 	 
	NLS
    Pharmaceutics Ltd.	 	 
	 	 	 
	/s/
    Alexander Zwyer	 	/s/
    Ronald Hafner
	Alexander
    Zwyer	 	Ronald
    Hafner
	Chief
    Executive Officer	 	Chairman
    of the Board of Directors


 



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