Ropeginterferon Alfa-2b (P1101) vs. Anagrelide in Essential Thrombocythemia Patients With Hydroxyurea Resistance or Intolerance
Key claim: A Phase 3 randomized active-controlled trial is comparing efficacy, safety, and tolerability of ropeginterferon alfa-2b (P1101) versus anagrelide after 12 months as second-line therapy in essential thrombocythemia patients with hydroxyurea resistance or intolerance.
Abstract
This is a Phase 3 open-label, multicenter, randomized, active-controlled study designed to compare the efficacy and safety and tolerability of P1101 compared with ANA after 12 months of treatment as second-line therapy for subjects with ET who have had a suboptimal or failed response to HU.
Why this matters
ET’s second-line landscape after hydroxyurea failure/intolerance has historically lacked direct comparative trials between the two most-used cytoreductive options, ropeginterferon alfa-2b and anagrelide. This Phase 3 head-to-head extends the SURPASS-ET signal (43% vs 6% response at 9–12 months) into a dedicated 12-month efficacy/safety/tolerability comparison, which — alongside bomedemstat’s MK-3543-006 and STP938 trials — will help define the emerging post-HU treatment hierarchy specific to ET natural history.