DBLZ reduced expression of Arg‐1 by ~50% with this single systemic dose, which compares favorably to previous studies of CSF‐1 receptor inhibition where ~70% in vivo knockdown of Arg‐1 expression in TAMs in orthotopic brain tumor models required daily repeated dosing of 40–100 mg/kg PLX3397.39, 42. Here, ARG1 is linked to brain neoplasm.