<p>Epoetin beta is identical in its amino acid and carbohydrate composition to erythropoietin that has been isolated from the urine of anemic patients. Erythropoietin is a glycoprotein that stimulates the formation of erythrocytes from its committed progenitors. It acts as a mitosis-stimulating factor and differentiation hormone. Erythropoietin is a glycoprotein that, as a growth factor, primarily stimulates the formation of erythrocytes from its committed progenitors. It acts as a mitosis-stimulating factor and differentiation hormone.</p>