HSB-1940

HSB-1940 is an investigational biologic therapy being developed for cancer immunotherapy. It is a proprietary "Quatrabody"—a conjugate composed of a novel anti-PD-1 Picobody, which is a small, cysteine-rich antibody fragment with ultralong CDR H3 sequences, coated onto Quatramers, a long half-life tumor-targeting nanoparticle platform. HSB-1940 is specifically engineered to bind and block *programmed cell death protein 1 (PD-1)*, including so-called "undruggable" or challenging epitopes not accessible to conventional antibodies, thereby potentiating immune-mediated tumor cell killing. The drug is designed to have higher binding affinity and efficiency at targeting PD-1 than currently approved biologics, and aims to provide an advantage in the immuno-oncology market by overcoming resistance mechanisms in solid tumors[1][2][4][7][9].