Novartis' Scemblix (asciminib) has received accelerated approval from the U.S. Food and Drug Administration (FDA) for the treatment of adult patients with newly diagnosed Philadelphia chromosome-positive chronic myeloid leukemia in chronic phase (Ph+ CML-CP). This approval marks a significant advancement in the treatment landscape for CML patients.
The accelerated approval is based on data from the ASC4FIRST Phase III trial, which compared once-daily Scemblix to investigator-selected standard of care tyrosine kinase inhibitors (TKIs), including imatinib, nilotinib, dasatinib, and bosutinib. The trial's primary endpoint was major molecular response (MMR) rate at week 48.
Superior MMR Rates with Scemblix
The ASC4FIRST trial demonstrated that Scemblix achieved superior MMR rates at week 48 compared to both investigator-selected standard of care TKIs and imatinib alone. This indicates a potentially more effective initial treatment option for patients with Ph+ CML-CP. The company noted that nearly 50% of chronic myeloid leukemia patients do not meet efficacy milestones (MMR) with current standard of care and almost 25% discontinue or switch therapies within one year of treatments.
Continued Approval Contingent on Confirmatory Evidence
It is important to note that continued approval for the newly diagnosed indication may be contingent upon verification and description of clinical benefit from confirmatory evidence. Novartis is expected to provide further data to support the long-term efficacy and safety of Scemblix in this patient population.
Implications for CML Treatment
This accelerated approval offers a new first-line treatment option for patients with Ph+ CML-CP. Scemblix's novel mechanism of action, as a STAMP inhibitor, provides an alternative approach to traditional TKIs, potentially addressing resistance and intolerance issues that can arise with existing therapies.