IO Biotech, Inc.

We are a clinical-stage biopharmaceutical company focused on developing new, immune-modulating, ready-to-use therapeutic cancer vaccines using our T-win® platform. Our T-win product candidates are designed to eliminate both tumor cells and immune-suppressive cells within the tumor microenvironment (TME) by activating and expanding T cells against target antigen-positive cells. This process modifies the TME, creating a more pro-inflammatory setting and enhancing anti-tumor activity by unleashing T-cell-mediated tumor destruction. We believe our product candidates could advance oncology treatment, amplifying immune-oncology effects across melanoma and other tumor types. Our primary therapeutic cancer vaccine candidate, IO102-IO103, known in the U.S. as Cylembio® (imsapepimut and etimupepimut, adjuvanted), targets cancer cells and immune-suppressive cells in the TME that express indoleamine 2,3-dioxygenase (IDO) and programmed death ligand 1 (PD-L1). In an investigator-initiated, single-arm Phase 1/2 trial involving 30 anti-PD-1/PD-L1 naïve patients with metastatic melanoma, Cylembio, combined with nivolumab (an anti-programmed cell death 1 (PD-1) checkpoint inhibitor), showed proof of concept. This combination increased the overall response rate (ORR) and median progression-free survival (PFS) compared to reported results with an anti-PD-1 antibody alone. Safety was the primary endpoint, immune response the secondary, and clinical efficacy (including objective response (OR), PFS, and overall survival (OS)) was the tertiary endpoint. The combination led to significant tumor regression and achieved rapid, deep, and lasting responses with a favorable tolerability profile, without adding systemic toxicity beyond what is typically observed with anti-PD-1 monotherapy in this patient group. As of the January 5, 2023 data cut, published in the May 2023 Journal for ImmunoTherapy of Cancer, we observed a confirmed ORR of 73% (per RECIST 1.1), a complete response rate (CRR) of 50%, and 25.5 months of PFS.