Table 3. Effects of therapy on JAK2... | American Society of Hematology

Table 3.

Effects of therapy on JAK2^V617F cell quantity, quality, and clonal expansion

	Phlebotomy	Hydroxyurea	Ruxolitinib	Ropeginterferon
Quantity	+	++	+++	+++
Comments	Rapid reduction of red cells and blood volume	Control of WBC, RBC, and platelets	Control of WBC, RBC, and platelets. Most reliable hematocrit control	Control of WBC, RBC, and platelets, sustained with molecular responses
Quality	–	–	+	+
Comments	Reinforces iron deficiency, activates HIF⁴²^,⁴⁶	Selection stress on bone marrow HSC⁶⁵	Reduced intracellular signaling⁴⁷	Targets and extinguishes JAK2^V617F-positive HSC⁶⁶
Clonal suppression	–	–	+	+++
Comments	VAF increases ∼1% per year⁶¹	Transient reduction in first year, then rebounds VAF increases ∼1% per year⁶⁰^,⁶⁷	Mild to moderate, but highly variable VAF reduction³^,⁶⁸^,⁶⁹	Consistent reduction in VAF VAF decreases ∼1% per month over 36 months⁶⁰^,⁶¹^,⁷⁰^,⁷¹

	Phlebotomy	Hydroxyurea	Ruxolitinib	Ropeginterferon
Quantity	+	++	+++	+++
Comments	Rapid reduction of red cells and blood volume	Control of WBC, RBC, and platelets	Control of WBC, RBC, and platelets. Most reliable hematocrit control	Control of WBC, RBC, and platelets, sustained with molecular responses
Quality	–	–	+	+
Comments	Reinforces iron deficiency, activates HIF⁴²^,⁴⁶	Selection stress on bone marrow HSC⁶⁵	Reduced intracellular signaling⁴⁷	Targets and extinguishes JAK2^V617F-positive HSC⁶⁶
Clonal suppression	–	–	+	+++
Comments	VAF increases ∼1% per year⁶¹	Transient reduction in first year, then rebounds VAF increases ∼1% per year⁶⁰^,⁶⁷	Mild to moderate, but highly variable VAF reduction³^,⁶⁸^,⁶⁹	Consistent reduction in VAF VAF decreases ∼1% per month over 36 months⁶⁰^,⁶¹^,⁷⁰^,⁷¹

EMH, extramedullary hematopoiesis; RBC, red blood cell; WBC, white blood cell.