Recombinant Interferon-α Reduces Thrombotic Events in Patients with Polycythemia Vera

Research from at the 12th International Congress on Myeloproliferative Neoplasms shows that rIFNα is superior to HU and PHL for reducing thrombotic risk in polycythemia vera (PV) patients.

Researchers enrolled 328 (165 men, 163 women) patients who were diagnosed with PV according to PVSG criteria, published Weill Cornell criteria, or WHO 2016 criteria. Demographic, clinical, laboratory, morphologic, and mutational data were all collected. The researchers used intention-to-treat analysis to assign patients to a first-line therapy (cytoreductive therapy for ≥1 consecutive year or PHL-O). All covariate differences were analyzed using χ2 tests while overall survival (OS) was measured by the Kaplan-Meier estimator. Thrombotic risk was assessed with a covariate-adjusted Cox proportional-hazards model.

According to the results, predisposing factors associated with thrombosis included uncontrolled HCT, increasing leukocytosis, and a first year PHL of five or more. The researchers observed that elevated HCT was the greatest contributor to thrombosis. Moreover, the results showed a weaker correlation between PLT count and thrombosis. The researchers noted that the apparent superiority of IFN over HU and PHL in this study is suggested by 10-year CIs of thrombosis of 3.2%, 18.0%, and 30.6%, respectively.

“Due to the potential for thrombosis to occur from disease onset, our data suggests the need for early cytoreduction and shows for the first time that rIFNα is superior to HU and PHL for reducing thrombotic risk,” the study authors wrote. “Multivariate analysis indicates that HCT and WBC values and PHL rates correlate with 10-year thrombosis after diagnosis. A new prognostic scoring system incorporating these parameters is indicated.”

Krichevsky S, et al. Recombinant Interferon-α Reduces Thrombotic Events in Patients with Polycythemia Vera. Presented at the 12th International Congress on Myeloproliferative Neoplasms; October 24-25, 2019; New York, NY.