In Real-World Setting, Treatment Efficacy for CML in Line With Promising Recent Data

Asciminib is safe and efficacious for patients with chronic myeloid leukemia (CML) without treatment alternatives in real-world clinical practice, suggests findings published online in Blood Cancer Journal.

“Asciminib is a first-in-class STAMP (Specifically Targeting the ABL Myristoyl Pocket) inhibitor that potently and specifically inhibits BCR-ABL1 via binding to a pocket distinct from the ATP binding site of the kinase…” researchers explained in a letter to the editor. “Asciminib has been evaluated in a phase 1 study in patients with Ph-positive leukemia failing prior tyrosine-kinase inhibitors, with promising results.”

The letter shared data on outcomes in 31 BCR-ABL1-positive patients with CML treated with asciminib under a compassionate access program at 25 clinics in Spain.

After a median 8.8 months of asciminib treatment, cumulative rates for reaching or at least maintaining previous response were 66% for complete cytogenetic response (CCyR) and 41% for major molecular response (MMR), researchers wrote. During a median 10.2-month follow-up, 90% maintained and 55% of patients improved baseline response.

“Despite adequate overall responses, it is important to mention that probabilities to achieve CCyR in resistant patients without CCyR at baseline was 33% (3/9), which is significantly lower compared to results observed in phase I trial,” researchers wrote. “One explanation could be the more pretreated population in our study; however, ongoing studies will clarify probabilities of achieving optimal responses in patients without baseline responses.”

The letter also reported a good safety profile in the patient population, which researchers pointed out should be considered at high risk of experiencing side effects because most patients were intolerant to previous tyrosine-kinase inhibitors.

Overall, 58% of patients experienced treatment-emergent adverse events of any grade, and about one-third reported grade 3 or 4 treatment-emergent adverse events. No patients discontinued asciminib because of side effects, according to the report.

“In conclusion, the results presented, in line with data from the phase 1 study, show asciminib as a safe and efficacious drug for CML patients without treatment alternatives in common clinical practice,” researchers wrote. “Further ongoing studies will provide information related the type of patients that would benefit the most from this new treatment approach.”

Reference:
Garcia-Gutiérrez V, Luna A, Alonso-Dominguez JM, et al. Safety and efficacy of asciminib treatment in chronic myeloid leukemia patients in real-life clinical practice. Blood Cancer J. 2021;11(16). doi:10.1038/s41408-021-00420-8