Exhibit 23.1

CONSENT OF INDEPENDENT REGISTERED PUBLIC ACCOUNTING FIRM

We hereby consent to the incorporation by reference in this Amendment No.1 to the Registration Statement on Form S-3/A of Celldex Therapeutics, Inc. of our report dated March 26, 2020 relating to the financial statements, which appears in Celldex Therapeutics Inc.’s Annual Report on Form 10-K for the year ended December 31, 2019. We also consent to the reference to us under the heading “Experts” in such Registration Statement.

/s/ PricewaterhouseCoopers LLP
Boston, Massachusetts

June 11, 2020