FDA Approves Asciminib (Scemblix) for Newly Diagnosed Philadelphia Chromosome-Positive CML
Key Insights
The FDA has granted accelerated approval to asciminib (Scemblix) for adult patients with newly diagnosed Philadelphia chromosome-positive chronic myeloid leukemia (search) (Ph+ CML (search)) in chronic phase.
The approval was based on the ASC4FIRST trial, a randomized, active-controlled, open-label study that compared asciminib to investigator's choice of tyrosine kinase inhibitor (TKI).
Asciminib demonstrated a significantly higher major molecular response (MMR) rate at 48 weeks compared to TKIs (68% vs. 49%, p < 0.001) in the ASC4FIRST trial.
The U.S. Food and Drug Administration (FDA) has granted accelerated approval to asciminib (Scemblix) for the treatment of adult patients with newly diagnosed Philadelphia chromosome-positive chronic myeloid leukemia (search) (Ph+ CML (search)) in the chronic phase. This approval marks a significant advancement in the treatment landscape for CML, offering a new first-line option for patients.
The approval was primarily based on the results of the ASC4FIRST trial (NCT04971226), a multicenter, randomized, active-controlled, open-label study. In this trial, 405 patients were randomized in a 1:1 ratio to receive either asciminib or the investigator’s choice of a selected tyrosine kinase inhibitor (TKI), which could be imatinib (Gleevec), nilotinib (Tasigna), dasatinib (Sprycel), or bosutinib (Bosulif).
Superior Efficacy of Asciminib
The primary efficacy outcome of the ASC4FIRST trial was major molecular response (MMR) at 48 weeks. Asciminib demonstrated a statistically significant and clinically meaningful improvement in MMR rates compared to TKIs. Specifically, the MMR rate in the asciminib arm was 68% (95% CI, 61-74), while the TKI arm achieved an MMR rate of 49% (95% CI, 42-56), with a p-value of less than 0.001. Further analysis revealed MMR rates of 69% (95% CI, 59-78) and 40% (95% CI, 31-50) in the asciminib and TKI groups, respectively (p-value <0.001).
Safety Profile
The safety profile of asciminib was evaluated in a pooled population that included patients with both newly diagnosed and previously treated Ph+ CML (search) in the chronic phase. The most common adverse effects, occurring in 20% or more of patients, were musculoskeletal pain, rash, fatigue, upper respiratory tract infection, headache, abdominal pain, and diarrhea. Common laboratory abnormalities observed in 40% or more of patients included decreased lymphocyte count, decreased leukocyte count, decreased platelet count, decreased neutrophil count, and decreased corrected calcium.
Dosing and Administration
The FDA recommends a dosing regimen of asciminib at 80 mg once per day or 40 mg twice per day, administered at approximately 12-hour intervals.
This approval provides a valuable new option for patients newly diagnosed with Ph+ CML (search), potentially improving treatment outcomes and quality of life.