Sensei Biotherapeutics (SNSE) investor relations material

Key presentations and announcements

• Highlighted SylvesterTOG as the first credible VISTA-targeted therapy advancing toward mature efficacy signals, with phase one/two dose expansion results to be presented at ESMO Congress in October 2025.

• Emphasized SylvesterTOG's selective binding in the acidic tumor microenvironment, sparing healthy tissue and avoiding toxicity that halted earlier VISTA programs.

• Noted multiple responses in PD-L1 resistant tumors, a market with limited options and significant commercial potential, with VISTA expressed in most solid tumors.

• Announced a collaboration with Regeneron to evaluate SylvesterTOG in combination with Libtayo, expanding the therapy's reach across various tumor types.

• Confirmed a strong financial position with a cash runway into 2026 to support upcoming milestones and phase two trial preparations.

Clinical data and industry analysis

• Phase one trial demonstrated a favorable safety profile, with no dose-limiting toxicities and only low-grade, manageable cytokine release events.

• Dose expansion focused on hot tumors resistant to PD-1, showing tumor shrinkage in about half of patients and durable responses in several cases.

• All PD-1 resistant patients with tumor shrinkage remain on therapy, indicating potential for long-term benefit.

• Compared to published benchmarks, SylvesterTOG shows improved durability and progression-free survival in a tough-to-treat population.

• Most adverse events in the expansion cohort were grade one or two, with no severe toxicities observed.

Forward-looking statements and strategic plans

• Full phase one/two dose expansion data, including six-month progression-free survival, will be presented at ESMO in October 2025.

• Plans to initiate multiple phase two studies in 2026, targeting both unmet medical needs and commercial opportunities.

• The ESMO mini oral session is expected to be a major inflection point for VISTA as a therapeutic target.

• The company aims to expand on its phase two strategy post-ESMO, with further details to be provided.

• Investors are offered a unique opportunity to participate in the first successful unlocking of VISTA's myeloid biology.