Marrowstimulating

Marrow-stimulating refers to therapies and agents that increase activity of the bone marrow to produce blood cells, with the aim of preventing or treating cytopenias, aiding recovery after cytotoxic therapy, or facilitating stem cell mobilization for transplantation. These agents are used in oncology, nephrology, hematology, and related fields to support hematopoiesis.

The main classes include granulocyte colony-stimulating factors (G-CSFs) such as filgrastim and pegfilgrastim, which stimulate neutrophil production; granulocyte-macrophage colony-stimulating factors (GM-CSFs) such as sargramostim, which promote multiple lineages of white blood cells; erythropoiesis-stimulating agents (ESAs) such as epoetin alfa and darbepoetin alfa, which enhance red blood cell production; and thrombopoietin receptor agonists such as romiplostim and eltrombopag, which stimulate platelet production. Interleukins like oprelvekin have also been used historically to support platelet production. In stem cell mobilization, G-CSFs are often used with agents like plerixafor to harvest peripheral blood stem cells for transplantation.

Mechanistically, these agents bind receptors on hematopoietic progenitor or precursor cells and activate signaling pathways (notably JAK-STAT) that promote proliferation and differentiation along specific lineages. They may also mobilize stem cells from the bone marrow into the peripheral blood.

Clinical use includes reducing duration of chemotherapy-induced neutropenia, treating anemia in chronic kidney disease, and enabling stem cell collection for autologous or allogeneic transplantation. Safety considerations include bone pain, fever, splenomegaly, leukocytosis, and, in some contexts, risks of thrombosis or disease progression in certain hematologic conditions. Regulatory guidance and clinical guidelines guide their use and monitoring.