The ASCEMBL phase 3 trial's end-of-study analysis, with nearly 4 years of follow-up, confirms that asciminib—a first-in-class STAMP inhibitor targeting the ABL myristoyl pocket—remains significantly superior to bosutinib in patients with chronic-phase CML who have failed two or more prior tyrosine kinase inhibitors. At week 156, asciminib achieved a major molecular response rate of 33.8% versus only 10.5% with bosutinib, an adjusted difference of 23.2%. Asciminib also caused fewer grade ≥3 adverse events and far fewer treatment discontinuations due to side effects. These durable long-term results reinforce asciminib as the preferred third-line or later therapy for resistant or intolerant CML patients.
