Sensei Bio creates tumor‑microenvironment‑activated biologics that employ engineered pH‑sensitive Fab domains to bind immunosuppressive targets only under the acidic conditions of solid tumors. The platform delivers monoclonal and bispecific antibodies with conditional activation, enhancing tumor exposure and reducing systemic toxicity for pharma and biotech immuno‑oncology programs.
Funding
$30M raised to dateRaised to date based on public sources. This may differ from the amount the company actually raised and is based only on what is publicly available on the internet.
AICCFounders
Product
Problem
Many immuno‑oncology targets, such as checkpoint proteins and myeloid‑derived suppressors, are expressed broadly on healthy tissues. This lack of selectivity leads to on‑target, off‑tumor toxicities, poor pharmacokinetics, and limited therapeutic windows, preventing effective treatment of solid tumors. Consequently, patients with cold, T‑cell‑excluded cancers have few viable options.
Solution
Sensei Bio’s Tumor‑Microenvironment‑Activated Biologics (TMAb) platform engineers monoclonal antibodies that become active only under the acidic conditions characteristic of the tumor microenvironment. By incorporating pH‑sensitive Fab domains and Fc engineering, the antibodies bind their immunosuppressive targets (e.g., VISTA, VSIG4, CD39, CD28) selectively within tumors while remaining inert in normal tissue. This conditional activation improves tumor exposure, reduces cytokine‑release syndrome and other systemic adverse events, and enhances pharmacokinetic profiles. The platform also supports bispecific formats that combine checkpoint blockade with costimulatory activation, further promoting T‑cell infiltration and tumor killing. Clinical‑stage candidates such as SNS‑101 (anti‑VISTA) are being evaluated as monotherapy and in combination with anti‑PD‑1 therapy in Phase 1/2 trials for advanced solid tumors. The TMAb approach can be extended to other tumor‑specific cues (redox potential, extracellular ATP) to broaden the druggable immuno‑oncology landscape.
Target Audience
The primary customers are pharmaceutical and biotech companies developing immuno‑oncology therapeutics, as well as clinical investigators and oncology centers seeking selective checkpoint inhibitors for solid‑tumor patients.
Features
- pH‑dependent antigen binding using engineered Fab domains that activate only at low extracellular pH (≈6.5) typical of the tumor microenvironment.
- Fc region optimized for myeloid cell engagement, driving pro‑inflammatory cytokine release within the tumor while sparing peripheral immune cells.
- Bispecific antibody designs (e.g., CD28 agonist paired with pH‑selective VISTA blockade) to provide localized costimulatory signaling without systemic toxicity.
- Conditional activation reduces on‑target, off‑tumor drug clearance, resulting in higher tumor‑to‑plasma exposure ratios.
- Platform flexibility to incorporate additional TME triggers such as redox potential or ATP concentration for next‑generation candidates.
- Pipeline includes four investigational antibodies targeting VISTA, VSIG4, CD39, and a CD28‑VISTA bispecific, each engineered for low‑pH selectivity.
- Clinical validation through a Phase 1/2 study of SNS‑101 as monotherapy and in combination with cemiplimab (anti‑PD‑1).