SBT115301

SBT115301 is a second-generation CD2-targeting fusion protein biologic developed by Sonoma Biotherapeutics for the treatment of autoimmune and inflammatory diseases. It is designed to selectively deplete and inactivate highly activated effector T cells (Teff), which are dominant in autoimmune pathology, while sparing regulatory T cells (Treg) and naive T cells. The drug consists of a fusion between lymphocyte function-associated antigen-3 (LFA-3; CD58), the cognate receptor for CD2, enabling it to bind to CD2 expressed at high levels on Teff cells. By targeting these pathogenic Teff populations, SBT115301 aims to restore immune homeostasis and tolerance. In preclinical studies and a Phase 1 clinical trial in healthy volunteers, SBT115301 demonstrated selective reduction of memory T cells with an acceptable safety profile aside from some decreases in CD4+ T cell counts at higher doses. The agent is being explored both as monotherapy and as part of combination regimens with engineered regulatory T cell therapies[1][3][4][6].