Multi-Peptide MHC Targeting: How Deck Bio Is Broadening T Cell Engager Access in Solid Tumors

These target proteins are independently regulated transcriptionally, so a tumor or lesion would have to lose expression of multiple independent proteins to escape' making antigen loss more difficult.⁴ In a priority indication for our lead program DBXO-1, non-small cell lung cancer (NSCLC), multi-targeting more than doubles the number of patients in analyzed cohorts that meet an expression threshold estimated to drive clinical response as compared to a single-target approach with a very popular pMHC target.

What are the priority indications for DBXO-1, and what technology platforms support it?

Our priority indications are NSCLC, gastroesophageal cancer, head and neck cancer, and liver cancer because 30 to 50% of patients with these tumor types express our target signature at sufficient levels. They are also relatively well-immune-infiltrated tumors, which increases our likelihood of success for a first proof-of-concept.

On the platform side, specificity is ensured through dbScope, a comprehensive, sequence-agnostic workflow that tests binder reactivity against any peptides displayed in the HLA type of interest in healthy tissues. For DBXO-1 targeting a signature in HLA-A*02:01, [more than] 13,500 peptides have been detected by mass spectrometry to be displayed in that allele across healthy organs. When we run our lead binders through dbScope, we see a residual binding profile comparable to tebentafusp' which is encouraging for our current leads.

Our T cell engager platform [dbTCE] engages pMHC complexes using a stabilized soluble T cell receptor rather than a TCR-mimetic antibody fragment. Historically, soluble TCRs have suffered from low manufacturing yields and poor stability; we have identified a proprietary stabilization technology that brings the profile into ranges more comparable to monoclonal antibodies, potentially enabling lower-risk manufacturing and, if the data support it, subcutaneous administration.

Where is Deck Bio in its development timeline, and what does success look like at 2 and 5 years?

We are in preclinical stage, developing our development candidate for DBXO-1 by end of 2026 with a planned clinic entry in early 2028. Two-year success means a cleared IND [investigational new drug] and efficient patient enrollment' including navigating HLA typing requirements. Five-year success is clinical proof-of-concept, which means an appropriate safety profile and efficacy signal in a selected patient population, with a clear development plan to advance to phase 2 and phase 3.

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References

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2. Garcia-Lorenzo E, Dorta M, Doger B, Pedregal M, Moreno V. Landscape of T-cell engagers in solid tumors. Oncologist. 2026;31(5):oyag129. doi:10.1093/oncolo/oyag129

3. FDA. BLA 761228 Approval. Published January 25, 2022. Accessed June 22, 2026. https://www.accessdata.fda.gov/drugsatfda_docs/appletter/2022/761228Orig1s000ltr.pdf

4. Mungalov RV, Mushenkova NV, Chudakov DM, Turchaninova MA. Engaging T cells for cleanup. Front. Immunol. 2025;16:1551424. doi:10.3389/fimmu.2025.1551424