This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: Hematology, Subject name: Pharmacology
Which of the following is a Longer acting Erythropoietin derivative? 
Select and explain. 
A. Sargramostim, B. Darbepoetin alfa, C. Dornase alfa, D. Oprelvekin
B: Darbepoetin alfa
Answer: B: Darbepoetin alfa 
Explanation: Darbopoietin is a Long acting EPO derivative drug. It has a T1/2 24-36 hrs. So it is given once a week. Epoietin has a half life of 6-10 hrs. Uses - Anemia of chronic renal failure(CRF) Anaemia in AIDS patients treated with Zidovudine. Cancer chemotherapy induced anaemia. Preoperative increased blood production for Autologous transfusion during surgery. Oprelvekin is recombinant Interleukin-11 analogue (eleven) Sargramostim is recombinant GM-CSF analogue