Erythropoiesis-stimulating agent
Erythropoiesis-stimulating agents (ESA) are medications which stimulate the bone marrow to make red blood cells. They are used to treat anemia due to end stage kidney disease, chemotherapy, major surgery, or certain treatments in HIV/AIDS. In these situations they decrease the need for blood transfusions.
Source: Wikipedia — Erythropoiesis-stimulating agent (CC BY-SA 4.0)