China – based Jiangxi Jemincare Group has announced that it has received approval from the US Food and Drug Administration (FDA) to conduct a clinical study for its Category 1 drug JYB1907. The monoclonal antibody (mAb) targets glycoprotein A dominant repeat (GARP) and transforming growth factor – \u03b21 (TGF – \u03b21) and is being developed for the treatment of locally advanced or metastatic solid tumors.<\/p>\n\n\n\n
Mechanism of Action and Preclinical Results<\/strong> Preclinical research has demonstrated a favorable safety and efficacy profile for JYB1907. In various human tumor cell and PBMC – humanized tumor animal models, JYB1907 showed significant tumor growth inhibition. Notably, more than half of the mice in the ZR – 75 – 1 human breast cancer model experienced complete tumor regression. Additionally, when combined with a PD – L1 antibody, JYB1907 induced complete tumor regression in some mice in the A375 human melanoma model, significantly outperforming the anti – tumor effect of the PD – L1 antibody alone. These results highlight the potential pharmacodynamic enhancement effect of the JYB1907 combination therapy.<\/p>\n\n\n\n
GARP is a Type I transmembrane cell surface docking receptor that is highly expressed on activated regulatory T cells (Tregs) and platelets. It mediates the activity of TGF – \u03b21, which is a major cause of drug resistance during immune checkpoint inhibitor treatment. JYB1907 specifically binds to the GARP\/TGF – \u03b21 complex, blocking GARP – mediated TGF – \u03b21 signaling. This action reverses the immunosuppressive effects in the tumor microenvironment and enhances the anti – tumor immune response.<\/p>\n\n\n\n