TPO and Thrombocytopenia: The effectiveness of TPO in alleviating thrombocytopenia was initially evaluated in a placebo-controlled study involving rhesus monkeys exposed to 5-Gy total-body irradiation(TBI) using supraoptimal treatment with human recombinant TPO (10 μg/kg/d, subcutaneously, days 1–21 after TBI).[15, 16] In addition, it has been shown that in animals TPO is able to accelerate platelet recovery after myeloablative chemotherapy.