A Phase 3 Study of INCA033989 Versus Best Available Therapy in Participants With Essential Thrombocythemia
Key claim: A Phase 3 trial is evaluating INCA033989 versus best available therapy in CALR-mutant essential thrombocythemia patients who have previously received cytoreductive therapy.
Abstract
This study is being conducted to evaluate INCA033989 versus best available therapy in participants with essential thrombocythemia and a CALR mutation previously treated with cytoreductive therapy.
Why this matters
INCA033989 becomes the first mutant-CALR-selective therapy to reach Phase 3 in ET, marking a transition from proof-of-concept early-phase data to pivotal evaluation of a genotype-specific, potentially disease-modifying mechanism in the ~25–30% CALR-mutated ET subset. Alongside the Phase 3 bomedemstat (MK-3543-006/007) and ropeginterferon SURPASS-ET programs, this signals a shift in ET’s post-HU landscape from cytoreductive intensification toward mechanism-diverse, mutation-stratified options.