Dr Andorsky on Molecular Responses With Second-Line Asciminib in CP-CML

"We found that 42.9% of patients experienced a MMR…in the second-line [cohort], and we thought those were very positive results."

David J. Andorsky, MD, a medical oncologist and hematologist at Rocky Mountain Cancer Centers; as well as the associate chair of US Oncology Hematology Research, discusses interim results from the phase 2 ASC2ESCALATE study (NCT05384587) evaluating asciminib (Scemblix) dose escalation in patients with chronic myeloid leukemia in chronic phase (CP-CML) previously treated with 1 TKI.

The single-arm, open-label ASC2ESCALATE study enrolled adult patients with CP-CML who were either newly diagnosed or had received 1 prior ATP-competitive TKI. The primary end point of the study was major molecular response (MMR) at 48 weeks. This interim analysis focused on second-line patients who enrolled in the trial and received at least 1 dose of asciminib on or before the data cutoff date, with an earlier time evaluation point of molecular response rate at 24 weeks.

Results presented at the 2024 ASH Annual Meeting demonstrated high molecular response rates with asciminib at 24 weeks and early deep molecular responses (MR⁴ and MR^4.5), with consistent safety and tolerability. Andorsky reported that 42.9% of patients achieved MMR at 24 weeks, with a BCR::ABL1^IS levels of 0.1% or less on the international scale, which is considered the critical threshold to prevent disease progression or transition into accelerated phase, according to Andorsky. For a second-line trial, these results were promising, Andorsky emphasized.

Moreover, only 2 of 28 patients eligible for escalation to the next dose level required dose adjustment, Andorsky added. Most patients performed well and experienced benefit with the 80-mg daily starting dose, which is the current FDA-approved dose for asciminib, Andorsky stated. These results suggest that asciminib may be a beneficial treatment option with a manageable dosing regimen for patients with CP-CML receiving second-line therapy, Andorsky concluded.