By: Kerri Fitzgerald
A study compared second-line treatment options for essential thrombocythemia (ET) and found that ropeginterferon alfa-2b “outperformed” anagrelide in both efficacy and safety outcomes.
Harry Gill, MBBS, of the University of Hong Kong, presented the findings at the 2025 EHA Congress in Milan, Italy.
Ropeginterferon alfa-2b is a new-generation interferon-based therapy that has been used to treat polycythemia vera (PV). The active-controlled, open-label, multicenter, phase 3 SURPASS-ET study compared outcomes for 174 patients with ET who were resistant or intolerant to hydroxyurea and treated with ropeginterferon alfa-2b (n=91) or anagrelide (n=83) over 12 months.
A greater proportion of patients demonstrated a sustained response at both nine and 12 months in the ropeginterferon alfa-2b cohort (42.9% vs 6.0%; P=0.0001). Treatment with ropeginterferon alfa-2b also resulted in blood count normalization, maintenance or improvement of splenomegaly, symptom improvement or stability per the Myeloproliferative Neoplasm Symptom Assessment Form, and absence of hemorrhagic/thrombotic events.
One patient (1.1%) in the ropeginterferon alfa-2b group and 7 (8.8%) in the anagrelide group experienced an ET-related thrombotic event. There were no instances of progression to myelofibrosis or acute leukemia with ropeginterferon alfa-2b versus 3 cases (3.6%) with anagrelide.
JAK2V617F allele fraction declined from 33.7% to 25.3% at 12 months in the ropeginterferon alfa-2b arm compared with a decline from 39.7% to 37.3% with anagrelide.
Ropeginterferon alfa-2b was also associated with fewer treatment-related discontinuations (4.4% vs. 12.5%), treatment-related serious adverse events (2.2% vs 10.0%), and adverse events of special interest—psychiatric, ocular, immunologic, gastrointestinal, and cardiac, as well as major ET-related cardiovascular, hemorrhagic, or thrombotic events—(27.5% vs. 43.8%) compared with anagrelide.
“These findings indicate that [ropeginterferon alfa-2b] represents a superior second-line therapy for patients with ET, in addition to its established role in treating PV,” the authors concluded.
Reference
Gill H, Masarova L, Xiao Z, et al. Better safety and efficacy with ropeginterferon alfa-2b over anagrelide as second-line treatment of essential thrombocythemia in the topline results of the randomized phase 3 SURPASS-ET trial. Abstract #S102. Presented at the European Hematology Association 2025 Congress; June 12-15, 2025; Milan, Italy.
