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Exhibit 23.1

CONSENT OF INDEPENDENT REGISTERED PUBLIC ACCOUNTING FIRM

        We hereby consent to the incorporation by reference in the Registration Statements on Form S-8 (File Nos. 333-151728, 333-117602 and 333-162423) and on Form S-3 (File No. 333-143112 and 333-162613) of Celldex Therapeutics, Inc. of our report dated March 12, 2010 relating to the financial statements and the effectiveness of internal control over financial reporting, which appears in this Form 10-K.

/s/ PricewaterhouseCoopers LLP

Boston, Massachusetts
March 12, 2010

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Exhibit 23.1