IFNA1 and essential thrombocythemia: IFN-α therapy shows clinical efficacy in controlling myeloproliferation and relieving pruritus and other constitutional symptoms in ET: PEG-IFN-α-2a at 90 μg weekly resulted in an overall hematologic response rate of 81% in 39 ET patients and a decrease in JAK2V617F allele burden [32, 40].