Exhibit 10.28


 


AMENDMENT TO

AMENDED AND RESTATED CONSULTING AGREEMENT


 


This Amendment to the
Consulting Agreement (the “First Amendment”) is entered into between PhaseRx Inc., a Delaware corporation having
a place of business at 410 West Harrison Street, Seattle, WA 98119 (“Company”) corporation (“Company”)
and John A. Schmidt, Jr., M.D. LLC having a place of business at 709 7th Ave., Belmar, NJ 07719 Consultant”).


 


RECITALS


 


WHEREAS, the Consultant
and Company entered into a Consulting Agreement effectively dated November 1, 2010 (the “Agreement”), a copy
of which is attached hereto.


 


WHEREAS, Consultant
and Company desire to amend the Agreement to provide for Consultant to increase the available consulting time to eight hours per
week. Company shall continue to pay Consultant at the rates previously agreed to in the Agreement.


 


NOW, THEREFORE, Consultant
and Company agree as follows:


 


		1.0	Definitions



 


Unless the context clearly requires otherwise,
all capitalized terms as used herein shall have the same meanings as used in the Agreement.


 


		2.0	Amendment Date



 


This Amendment shall be effective as of
June 1, 2011.


 


		3.0	Amendments to Agreement



 


The parties agree that the Agreement shall
be amended as described in this Article 3.0.


 


		3.1	Amend Section 1 of Exhibit A to read as follows:



 


1.          Services.
Consultant (or, in the case of Services as a member of the board of directors of the Company, Dr. Schmidt) will render to Company
the following Services. The provisions related to Dr. Schmidt’s Services as a member of the board of directors of the Company
are being included herein as an administrative convenience. For the avoidance of doubt, nothing in the agreement shall in any way
limit or vitiate Dr. Schmidt’s duties and obligations to the Company under applicable law and nothing herein shall be construed
as giving Dr. Schmidt a contractual right to serve on the board of directors of the Company.


 


		·	Board Member: Serve as a member of the Company’s board of directors. Attend up to 6 meetings/year in person in
Seattle and approximately 6-8 board teleconferences as needed per year.



 




     


     


    

 


		·	Consultant: Provide expert consulting services to Company regarding research, development, clinical and business matters
relating to: (1) pH sensitive, membrane disruptive polymers for the intracellular delivery of therapeutics, diagnostics and reagents
and (2) the delivery of siRNA therapeutics (collectively, the “Field of Interest”). Consultant shall make himself
available to consult with the Company for up to an average of eight hours per week over the course of the year.



 


		3.1	Amend Section 2, Consultant Compensation, of Exhibit A
to read as follows:



 


Consultant


 


		·	$100,000 in cash per year, paid in equal quarterly installments in arrears.



 


		·	Company shall Consultant shall submit monthly invoices to the Company for any amounts owing under this Agreement and shall
include a summary of time spent on Company business. Each invoice will contain enough detail to enable Company to determine the
accuracy of the amount(s) billed. With each invoice, Consultant will provide: (a) a detailed itemized listing of all expenses incurred
under this Agreement, and (b) receipts for any individual expenses that exceed $50. Either an original or a copy may be submitted.



 


		·	Company shall reimburse Consultant for all reasonable, documented out-of-pocket expenses incurred by Consultant in performing
Services pursuant to this Agreement. Company shall also reimburse consultant for attendance at conferences that are pre-approved
by Company. Consultant shall submit to Company all statements for expenses incurred on a monthly basis.



 


		4.0	No Other Waivers or Modifications; Applicability of
Agreement



 


Except to the extent expressly modified
by Article 3.0 of this Amendment, no other covenant, term, provision, condition or agreement of the parties set forth in the Agreement
shall be deemed to be waived, modified or amended in any way by this Amendment. All of the recitals, covenants, terms, provisions,
conditions and agreements of the parties set forth in the Agreement shall be deemed applicable to this Amendment.


 


		5.0	Entire Agreement



 


The Agreements, as modified by this Amendment,
constitute the entire agreement between the parties, and supersedes all prior oral or written agreements, commitments, or understandings
concerning the matters provided for herein.


 




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		6.0	Counterparts



 


This Amendment may be executed in any number
of counterparts or, if mutually agreeable to the undersigned authorized signatories for the parties, through the exchange by facsimile
or other electronic means (including electronically mailed PDF or similar imaging software) of duly-signed duplicates hereof, each
of which shall be deemed an original, but all of which together shall constitute one and the same instrument.


 


IN WITNESS WHEREOF, the parties hereto have
executed this Agreement as of the Effective Date.


 


	PHASERX INC.	 	CONSULTANT
	 	 	 	 	 
	By:	/s/ Andrew J. Leon	 	By:  	/s/ John A. Schmidt, Jr.
	 	 	 	 	 
	Print Name:	Andrew J. Leon	 	Print Name: 	John A. Schmidt, Jr., M.D.
	 	 	 	 	 
	Title:  	Vice President, Intellectual Property	 	Title:	 
	 	 	 	 	 
	Address:   	410 W. Harrison St., Ste 300	 	Address: 	709 7th Ave.
	 	 	 	 	 
	 	Seattle, WA	 	 	Belmar, NJ
	 	 	 	 	 
	 	98119	 	 	07719
	 	 	 	 	 
	Date: 	7/5/2011	 	Date: 	6/22/11


 




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