Novartis' Scemblix, with novel mechanism of action, shows superior, long-term efficacy

Swiss pharma major Novartis (NOVN: VX) today announced longer-term follow-up data from the Phase III ASCEMBL trial for patients with Philadelphia chromosome-positive chronic myeloid leukemia in chronic phase (Ph+ CML-CP) previously treated with two or more tyrosine kinase inhibitors (TKIs), presented at the 2022 American Society of Clinical Oncology (ASCO) Annual Meeting.

In this analysis, the proportion of patients in the Scemblix (asciminib) arm (n=157) who achieved a major molecular response (MMR) at 96 weeks was more than double that in the Bosulif (bosutinib) arm (n=76) (37.6% versus 15.8% [P=.001]), substantially increasing from previous analyses. Additionally, the probability of maintaining MMR for at least 72 weeks for patients treated with Scemblix was 96.7% (95% CI, 87.4%–99.2%), reflecting long-term durability of efficacy.

Despite longer duration of exposure for patients in the Scemblix arm – with a median of 23.7 months vs 7.0 months for patients in the Bosulif arm – the updated 96-week analysis showed the proportion of patients treated with Scemblix who discontinued treatment due to adverse events (AEs) continued to be more than three times lower than those treated with Bosulif (7.7% vs 26.3%). No new on-treatment deaths were reported since the primary analysis at 24 weeks.