EXHIBIT 4.2




 


FIRST AMENDMENT TO

SECURED PROMISSORY NOTE


 


This First Amendment to Secured Promissory
Note (“Amendment”) is made and entered into as of September 28, 2015, by and between CASI Pharmaceuticals, Inc.
(the “Debtor”), and Talon Therapeutics, Inc. (the “Holder”).


 


BACKGROUND


 


WHEREAS, the Debtor and the Holder
are parties to that certain Secured Promissory note, dated as of September 17, 2014 (the “Note”);


 


WHEREAS, the Debtor and the Holder
desire to amend the Note as set forth below;


 


WHEREAS, pursuant to paragraph 11
of the Note, the Note may be amended by an agreement in writing signed by the party against whom enforcement of any waiver, change,
modification or discharge is sought; and


 


WHEREAS, the Debtor and the Holder
represent all parties to the Note and agree to amend the Note as set forth below.


 


AGREEMENT


 


NOW, THEREFORE, intending to be legally
bound hereby, the parties hereto agree as follows:


 


1.            
Existing Definitions. All capitalized terms used and not otherwise defined herein shall have their respective
meanings as set forth in the Note.


 


2.            
Amendment. Paragraph 2 of the Note is hereby amended and restated in full as follows:


 


“ Interest Rate; Maturity Date. Interest
shall accrue on the outstanding balance of the principal sum evidenced hereby at the rate of 0.50% per annum from the date hereof.
Interest shall be payable in arrears to the Holder on the date that is twelve (12) months after the date of this Note. The entire
unpaid principal balance of this Secured Promissory Note (the “Note”), together with all accrued but unpaid interest,
shall be and become due and payable in full on the date that is thirty (30) months after the date of this Note (the “Maturity
Date”). Any amount of principal and/or interest hereon which is not paid when due, whether at stated maturity, by acceleration
or otherwise, shall bear interest from the date when due until said principal and/or interest amount is paid in full, at the lesser of
(a) an interest rate equal to two percent (2%) per annum in excess of the interest rate set forth above, and (b) the highest rate
of interest allowable under applicable law.”


 


3.            
No Other Amendments. Except for the amendment specified in Section 2 of this Amendment, this Amendment shall
not be deemed to effect any amendment, modification or waiver of any provision of the Note.


 


4.            
Governing Law. This Amendment is to be construed and governed by the Laws of the State of Delaware (without
giving effect to principles of conflicts of laws).


 






    	 		 



     


    

 


5.            
Counterparts. This Amendment may be executed in two or more counterparts, all of which shall be considered
one and the same agreement and shall become effective when one or more counterparts have been signed by each of the parties hereto
and delivered to the other parties, including delivery by facsimile or other electronic means, it being understood that all parties
need not sign the same counterpart.


 


 


 


 


 


 


[signature pages follow]


 




    	 	2	 



     


    

 


IN WITNESS WHEREOF, each of the parties
hereto has executed this Amendment as of the date first set forth above.


 





	 	DEBTOR:	 
	 	 	 	 
	 	CASI PHARMACEUTICALS, INC.	 
	 	 	 	 
	 	 	 	 
	 	By:	/s/ Ken K. Ren	 
	 	Name:	Ken K. Ren	 
	 	Title:	Chief Executive Officer	 







  


 


 


 


 


 


 


 


 


 


 


 


 


 


Signature page to First Amendment to
Promissory Note


 







    	 		 



     


    

 


IN WITNESS WHEREOF, each of the parties
hereto has executed this Amendment as of the date first set forth above.


 





	 	HOLDER:	 
	 	 	 	 
	 	TALON THERAPEUTICS, INC.	 
	 	 	 	 
	 	 	 	 
	 	By:	/s/ Kurt A. Gustafson	 
	 	Name:	Kurt A. Gustafson	 
	 	Title:	Chief Financial Officer	 







 


 


 


 


 


 


 


 


 


 


 


 


 


 


 


 


Signature page
to First Amendment to Promissory Note