ABOUT US THE SCIENCE PIPELINE NEWS CONTACT INVESTORS Technology TOBI™ Platform HCW Biologics has combined a deep understanding of disease-related immunology with expertise in advanced protein engineering to develop TOBI™ (Tissue factOr-Based fusIon), a proprietary immunotherapeutic drug design and discovery platform¹. By harnessing this modular and tunable technology, we have generated a novel pipeline of product candidates that we believe are capable of activating and targeting desired immune responses while also blocking unwanted immunosuppressive activities¹. Built around a Tissue Factor (TF) scaffold, the TOBI platform has the potential to pack multiple protein targets, including cytokines, single-chain antibodies, and ligands, into a fusion molecule capable of engaging immunostimulatory functions and addressing many signaling pathways simultaneously. Some of these fusion protein complexes have ex vivo and in vivo applications for stimulating natural killer (NK) and T cells for cancer-cell and senescent-cell killing and blocking immunosuppression. Moreover, the TOBI platform is reproducible and suitable for cGMP manufacturing¹. Liu B, et al. Bifunctional TGF-β trap/IL-15 protein complex elicits potent NK cell and CD8+ T cell immunity against solid tumors. Mol Ther. 2021 Oct 6;29(10):2949-2962. About Us Leadership and Board The Science TOBI™ Platform Our Focus Pipeline News News Releases Publications Contact General Inquiries Careers Investors Copyright © 2021 HCW Biologics Inc.

ABOUT US THE SCIENCE PIPELINE NEWS CONTACT INVESTORS PUBLICATIONS Bifunctional TGF-β trap/IL-15 Protein Complex Elicits Potent NK Cell and CD8+ T Cell Immunity Against Solid Tumors Molecular Therapy, Liu B. et al, October 6th 2021 Publications A Fusion Protein Complex that Combines IL12, IL15, and IL18 Signaling to Induce Memory-like NK Cells for Cancer Immunotherapy Cancer Immunol Res, Becker-Hapak M. et al., September 9th 2021 Publications About Us Leadership and Board The Science TOBI™ Platform Our Focus Pipeline News News Releases Publications Contact General Inquiries Careers Investors Copyright © 2021 HCW Biologics Inc.