Asciminib (STAMP inhibitor; ABL myristoyl-pocket) delivers rapid MR2/MR3 with low discontinuation in 1L US CML-CP RWE

Asciminib (SCEMBLIX) is a first-in-class BCR::ABL1 “STAMP” inhibitor that binds the ABL myristoyl pocket (allosteric), here used as first-line therapy for newly diagnosed Ph+ CML-CP (no T315I) in a US retrospective physician-panel chart review (n=98; Jan–Oct 2024 starts; median follow-up 51.3 weeks). By 48 weeks, Kaplan–Meier cumulative molecular response rates were MR2 (BCR::ABL1≤1%) 91.0% (median 17.0 weeks), MMR/MR3 (≤0.1%) 70.4% (median 32.1 weeks), and MR4 (≤0.01%) 42.6% (median not reached), with 7.3% discontinuation and no discontinuations for AEs; cardiovascular AEs were uncommon (e.g., hypertension 4.1%, heart failure 3.1%, QTc prolongation 2.0%) and no progressions/deaths observed—numerically consistent with ASC4FIRST week-48 MMR 67.7% and discontinuation for AEs 4.5%, and higher than historical imatinib MMR at 12 months (40%).