Exhibit 32.2

Certification of

Principal Financial Officer

Pursuant to Section 906 of the Sarbanes-Oxley Act of 2002

I, Garrett Gray, Principal Financial Officer of Checkpoint Therapeutics, Inc. (the “Company”), in compliance with Section 906 of the Sarbanes-Oxley Act of 2002, hereby certify that, to the best of my knowledge, the Company’s Quarterly Report on Form 10-Q for the period ended March 31, 2017 (the “Report”) filed with the Securities and Exchange Commission:

• Fully complies with the requirements of Section 13(a) or 15(d) of the Securities Exchange Act of 1934; and

• The information contained in the Report fairly presents, in all material respects, the financial condition and results of operations of the Company.

/s/ Garrett Gray 

Garrett Gray

Vice President, Finance and Accounting 

(Principal Financial Officer) 

May 10, 2017