Interferon Alpha Has a Strong Anti-tumor Effect in Philadelphia-negative Myeloproliferative Neoplasms

Currently the cytoreductive approach with hydroxyurea remains the backbone treatment in myeloproliferative neoplasms. A valid, but not common alternative is interferon alfa (IFN-alpha). We prospectively assessed 63 patients with Philadelphia-negative myeloproliferative neoplasms treated with either hydroxyurea or IFN-alpha. Our data support IFN-alpha as a more suitable therapeutic option owing to its more profound hematologic and molecular responses and long-term disease control. Background: Despite the important progress in the research of myeloproliferative neoplasms (MPN), treatment options are still limited. Currently, a cytoreductive approach is the backbone treatment, with hydroxyurea (HU) being the most important agent. However, this drug is not always well-tolerated and has been questionably linked to a potential leukemogenic effect. A valid alternative is interferon alfa (IFN-alpha), but it is reserved for selected patients owing to the more frequent side effects and the lack of final results from the studies directly comparing IFN-alpha with HU, which is why we provided the results of the so far largest real-life analysis. Patients and Methods: From 2000 to 2016, 63 patients with Philadelphia-negative MPN prospectively received either HU or IFN-alpha. Results: During a median follow-up period of 121 months (range, 88-168 months), 97% of the patients treated with IFN-alpha achieved a hematologic response (60% complete, 37% partial) compared with 78% in the HU group (56% complete, 20% partial; P < .01). Molecular responses were limited to patients treated with IFN-alpha. IFN-alpha was well-tolerated with no secondary malignancy, whereas HU was associated with more toxic events and cases of leukemic transformation. A significantly longer progression-free survival (5.0 vs. 3.1 years; P <.001) and overall survival (7.8 vs. 5.8 years; P = .006) were observed in the IFN-alpha group compared with the HU cohort. Conclusion: Our data support IFN-alpha as a more valid therapeutic option owing to its more profound hematologic responses, durable molecular remissions, long-term disease control, and reduced risk of leukemic transformation with a favorable toxicity profile. (C) 2019 Elsevier Inc. All rights reserved.