Novartis' Updated ASCEMBL Study Showed Sustained Efficacy Vs Bosutinib In Chronic Myeloid Leukmia

(RTTNews) - Novartis' (NVS) Scemblix demonstrated sustained response rate in 48-week data from the Phase III ASCEMBL study in patients with chronic myeloid leukemia.

In this analysis, the major molecular response (MMR) rate at 48 weeks was 29.3% for patients treated with Scemblix vs. 13.2% for patients in the Bosulif arm, which is consistent with a doubling of the efficacy at 24 weeks (25% vs. 13% [P=0.029])1-4.

The proportion of patients treated with Scemblix who experienced adverse reactions leading to discontinuation was more than three times lower than those in the Bosulif arm (7.1% vs. 25%).

In this updated analysis, responses were also durable, with 60 out of 62 patients on Scemblix maintaining MMR at time of their last assessment. Scemblix continued to deliver more favorable deep molecular responses (MRs) with MR4 and MR4.5 rates at 48 weeks of 10.8% and 7.6%, compared to 3.9% and 1.3% in patients treated with Bosulif, respectively. With a longer duration of exposure, the safety and tolerability profile remains consistent with the primary analysis of the ASCEMBL trial.

The company specified that the data support longer-term use of Scemblix in patients with chronic myeloid leukemia (CML) who have previously struggled with intolerance and resistance to at least two prior tyrosine kinase inhibitor treatments.

Scemblix is the first FDA-approved CML treatment that works by binding to the ABL myristoyl pocket. This novel mechanism of action, also known in scientific literature as a STAMP inhibitor, can help address resistance to TKI therapy in patients with CML and overcome mutations at the defective BCR-ABL1 gene, which is associated with the over-production of leukemic cells.

The company stated that the Scemblix received FDA approval in October 2021 and is currently available for physicians to prescribe to appropriate patients in the US. Scemblix continues to be studied across multiple lines of treatment for chronic myeloid leukemia in chronic phase (CML-CP).