Median concentration of ADP required to cause 50% maximum aggregation of platelets in vitro (ADP₅₀ ) in patients receiving PEG-rHuMGDF rHuMGDF 0.03 and 0.1 μg/kg (▴, n = 6), 0.3 μg/kg (▾, n = 3), PEG-rHuMGDF 1.0 μg/kg (♦, n = 11), PEG-rHuMGDF 3.0 μg/kg (•, n = 3) PEG-rHuMGDF 5.0 μg/kg (□, n = 3), and placebo (▵, n = 7). Samples were taken before chemotherapy on day 1 and before PEG-rHuMGDF on day 2.