European Commission has approved Scemblix (asciminib) for treating adult patients with Philadelphia chromosome-positive chronic myeloid leukemia. Scemblix is indicated for patients who were previously treated with two or more tyrosine kinase inhibitors (TKIs). Novartis is the market authorization holder of Semblix.
In June 2022, the Committee for Medicinal Products for Human Use (CHMP) gave a positive recommendation for the approval of Scemblix. The approval was based on the Phase 3 ASCEMBL trial, in which patients with CML previously treated with two or TKI inhibitors were randomized in a 2:1 ratio to receive asciminib 40 mg twice daily vs. bosutinib 500 mg once daily. The primary endpoint was the major molecular response (MMR) at week 24. The major molecular response was 25.5% in the Scemblix arm compared to 13.2% in patients on bosutinib.
Novartis also announced that fewer grade ≥3 adverse events were reported in Scemblix (50.6%) arm compared to the bosutinib arm (60.5%). Scemblis showed superior efficacy and a better safety profile compared to bosutinib.
TKIs act by binding to the ATP site of BCR-ABL1, thereby stopping kinase activity. Scemblix acts by binding to the ABL myristoyl pocket, widely called a STAMP inhibitor (Specifically Targeting the ABL Myristoyl Pocket). It is a novel, first-in-class STAMP inhibitor that blocks the kinase activity of BCR-ABL1.
In Europe, nearly 6,300 patients are diagnosed with CML every year. A significant proportion of patients have intolerance or resistance to TKI inhibitors.