BLU-852

BLU-852 is a **highly selective and potent small molecule inhibitor of MAP4K1 (hematopoietic progenitor kinase 1, HPK1)** in preclinical development as a cancer immunotherapy agent[1][2][3][5]. It was developed to overcome limitations of prior MAP4K1 inhibitors by providing strong selectivity over related kinases such as lymphocyte-specific protein tyrosine kinase (LCK) and MAP4K4, with more than 100-fold selectivity over 97% of the kinome in binding assays[2][5]. MAP4K1 is an immunokinase involved in the negative regulation of immune cell activation, particularly in T cells, B cells, and dendritic cells. Inhibition of MAP4K1 results in enhanced T cell receptor (TCR) signaling, increased immune cell activation, and robust anti-tumor immunity[5]. BLU-852 has demonstrated in preclinical models: - enhancement of intratumoral immune cell activation - overcoming of T cell suppression (including PGE2 and Treg-mediated suppression) - increased production of interleukin 2 (IL2) in stimulated T cells - reduction in tumor burden both as monotherapy and in combination with checkpoint inhibition (such as anti-PD-L1 therapy) BLU-852 is under development by Blueprint Medicines, in collaboration with Roche, with anticipated transition toward early-phase clinical trials for oncology indications[1][2][3][4][5].