White blood cells are critical for fighting infections, stimulating the immune system to attack cancer cells, and clearing plaque from aged brains. Granulocyte-Macrophage Colony-Stimulating Factor (GM-CSF) stimulates production of multiple types of white blood cells, including neutrophils, macrophages, dendritic cells, and microglia. Currently marketed GM-CSF products are administered by daily injection. Our long-acting GM-CSF analog, BBT-007, can be administered less frequently and with greater efficacy than GM-CSF in animal disease models.