SB-728mR-HSPC

**SB-728mR-HSPC** is an investigational cell therapy consisting of autologous CD34+ hematopoietic stem/progenitor cells (HSPC) genetically modified using zinc finger nuclease (ZFN) mRNA (SB-728mR) delivered via electroporation to disrupt the CCR5 gene. This modification aims to block HIV-1 entry by eliminating the CCR5 co-receptor, a critical target for R5-tropic HIV strains. Developed through collaboration between Sangamo Therapeutics and City of Hope, it targets HIV-1 infected patients, particularly immunological non-responders (INR) with suboptimal CD4+ T-cell recovery on antiretroviral therapy (cART). Preclinical studies demonstrated 40-70% CCR5 disruption efficiency, with acceptable cell viability, engraftment in NSG mice, and no tumorigenicity, supporting Phase 1 evaluation of safety, feasibility, and engraftment following busulfan conditioning.[1][3][4]