Dimeric erythropoietin is 6 times more efficient in vivo than monomer.

Six groups of 6 C57BL/6 mice were injected intraperitoneally, either with 3 times sodium chloride or with 3 times 300 U/kg, 900 U/kg, or 1800 U/kg monomeric hEpo (M) or with 3 times 300 U/kg or 600 U/kg dimeric hEpo (D) (as determined by proliferation assay). Hematocrit was determined 3 days before (D−3) and 8 days after (D8) the first injection. Mean hematocrit values (rectangles) and individual mouse hematocrits (lines) are given.