Celldex Therapeutics : Corporate Presentation

Targeted Antibody Therapeutics to Address Devastating Diseases

NASDAQ: CLDX April 2024

Safe Harbor Statement

This communication contains "forward-looking" statements within the meaning of the Private Securities Litigation Reform Act of 1995. All statements other than statements of historical fact are statements that could be forward-looking statements. You can identify these forward- looking statements through our use of words such as "may," "will," "can," "anticipate," "assume," "should," "indicate," "would," "believe," "contemplate," "expect," "seek," "estimate," "continue," "plan," "point to," "project," "predict," "could," "intend," "target," "potential" and other similar words and expressions of the future. These forward-looking statements are subject to risks and uncertainties that may cause actual future experience and results to differ materially from those discussed in these forward-looking statements. Important factors that might cause such a difference include, but are not limited to, the timing, cost and uncertainty of obtaining regulatory approvals for product candidates; our ability to develop and commercialize products before competitors that are superior to the alternatives developed by such competitors; the validity of our patents and our ability to avoid intellectual property litigation, which can be costly and divert management time and attention; and the other factors listed under "Risk Factors" in our filings with the SEC, including Forms 10-K,10-Q and 8-K. Celldex does not undertake any obligation to release publicly any revisions to such forward-looking statement to reflect events or circumstances after the date hereof or to reflect the occurrence of unanticipated events.

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Leading the science at the intersection of mast cell biology and the development of transformative antibody therapeutics

• Lead product barzolvolimab: unique mast cell depleting antibody; potential for pipeline within a product
• • Rapid, profound & durable responses with favorable safety profile
  • • Topline Phase 2 CSU data presented 11/6/23, late breaking oral at AAAAI 2024 (2/24/24)
    • Phase 2 topline 52 week CSU data and Phase 2 CIndU data expected 2H 2024
    • Phase 1b PN data presented 11/7/23 ("Hot Topic" Oral; World Congress on Itch)
• Robust mAb and bsAb preclinical antibody platform supported by in-house manufacturing group developing next generation inflammatory and oncology programs
• Strong cash position - $423.6M as of 12/31/23; raised additional $400M+ 2/29/24
• Experienced team with extensive big pharma/biotech experience across multiple disease areas

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Strong Clinical Pipeline with Multiple Inflection Points

Inflammation

Bispecific Platform - Next Generation Inflammatory & Oncology

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Barzolvolimab: Clinically Validated with Compelling Profile

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Barzolvolimab: Multi-Billion Dollar Market Opportunity

Skin Mast Cells are the Primary Effector Cell in Urticaria

Significant medical need with limited or no treatment options

Patients suffer both physically and psychologically with impaired quality of life

"…severely disturbing disease to have, devastating, long-lasting and basically impacts on every aspect of life; sleep, interpersonal relationships, performance at work and school, hobbies, traveling, sports, all of these patients have stories to tell where their disease dominated their life…" - Marcus Maurer, MD

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Marcus Maurer, MD, Professor of Dermatology and Allergy, Charité - Universitätsmedizin, Berlin: Commentary from 7/12/21 data update call Image Sources:https://dermnetnz.org/topics/dermographism,

https://www.bbc.co.uk/bbcthree/article/d7ae42f3-b3ae-47ae-9464-eb8c328fe3dc