Ropeginterferon alfa-2b for adults with polycythemia vera: an updated perspective from approval to real-world clinical treatment

INTRODUCTION: Ropeginterferon alfa-2b (ROPEG) is an established long-acting interferon option for adults with polycythemia vera (PV). Since its regulatory approval, evidence from randomized trials has been complemented by long-term analyses, prospective studies, and an expanding real-world experience. AREAS COVERED: This review critically evaluates the evidence supporting ROPEG in adult PV, including PEGINVERA, PROUD-PV/CONTINUATION-PV and LOW-PV trials, long-term clinical and molecular outcomes, emerging biomarkers of clonal and inflammatory control, slow vs. accelerated dose titration, real-world effectiveness and safety, switching from peginterferon alfa-2a, cost-effectiveness, and the BESREMi® Pen approval. EXPERT OPINION: ROPEG has a strong evidence for durable hematologic control and progressive molecular responses, with real-world studies supporting its effectiveness in older, previously treated and hydroxyurea-intolerant patients. However, evidence for disease modification and prevention of thrombosis or transformation remains suggestive rather than definitive. Accelerated titration may shorten the time to response with manageable toxicities, but current evidence does not justify replacing the approved titration schedule routinely. Cost-effectiveness appears favorable in several healthcare models but remains highly dependent on drug prices, treatment persistence, and assumptions regarding long-term disease modification. The major priorities are prospective, harmonized real-world studies and randomized trials addressing clinically meaningful outcomes, optimal titration, treatment discontinuation, and patient selection.