Gisslinger H, Klade C, Georgiev P, et al. - A comparison between ropeginterferon alfa-2b (a new monopegylated interferon) vs hydroxyurea, the standard treatment for patients with polycythaemia vera, was performed over 3 years of treatment in phase 3, randomised, controlled, open-label, trials, named the PROUD-PV and CONTINUATION-PV trials (extension study of PROUD-PV). These studies were undertaken in 48 clinics in Europe. Eligibility criteria for inclusion were: age 18 years or older, and early stage polycythaemia vera (without history of cytoreductive therapy or less than 3 years of previous hydroxyurea therapy) diagnosed by WHO's 2008 criteria. Eligible patients were randomly allocated 1:1 to ropeginterferon alfa-2b (subcutaneously every 2 weeks, beginning at 100 μg) or hydroxyurea (orally starting at 500 mg/day). Findings revealed the effectiveness of ropeginterferon alfa-2b in inducing haematological responses among patients with early polycythaemia vera, who mainly presented without splenomegaly. In these patients, the non-inferiority of ropeginterferon alfa-2b to hydroxyurea with respect to haematological response and normal spleen size was not evident at 12 months. However, a continuous rise in response to ropeginterferon alfa-2b was noted over time with improved responses vs hydroxyurea at 36 months. As ropeginterferon alfa-2b induced high and durable haematological and molecular responses and was well-tolerated, hence, it was viewed as a valuable as well as a safe long-term treatment choice with features different from hydroxyurea.