ASCO

ASCO 2024: Asciminib bests standard care therapy in patients with newly diagnosed CML

June 3, 2024

While some patients with CML respond well to tyrosine kinase inhibitor (TKI) therapy, almost half of patients eventually need to change therapy due to drug resistance or difficulty tolerating the drug. The phase 3 ASC4FIRST clinical trial compared asciminib with available TKI therapies for chronic phase CML. It found asciminib—the first inhibitor classified as a Specifically Target the ABL Myristoyl Pocket (STAMP) drug—to be a potentially safer and more effective treatment option for people with newly diagnosed CML.

About the study

• A total of 405 patients with recently diagnosed chronic phase CML enrolled in cancer centers across 29 countries were randomly assigned to receive asciminib (n=201) or an investigator selected TKI (n=204).
• In the TKI arm, 102 patients received imatinib and 102 received a stronger second-generation TKI.
• Median age of the participants was 52 years and 65% were male. Around 54% of the participants were White and 44% were Asian.

Key findings

• As of November 28, 2023, treatment was ongoing for 86% of the patients receiving asciminib, 62% of the patients receiving imatinib, and 75% of the patients receiving a second generation TKI.
• After 48 weeks, 68% of patients in the asciminib arm had achieved a major molecular response compared to 49% in the TKI arm (including both imatinib and second generation TKIs).
• A deep molecular response was observed in 39% of patients in the asciminib arm vs. 21% in the TKI arm.
• In a subset analysis, patients who were selected to receive imatinib but randomized to asciminib were compared to the imatinib arm, and 100 patients selected for a second generation TKI but randomized to asciminib were compared to the second generation TKI arm. A major molecular response was reached in 40% of patients in the imatinib arm vs. 69% in the corresponding asciminib subset. In the second generation TKI arm, 58% of the patients reached a major molecular response vs. 66% in the corresponding asciminib subset.
• Most adverse events were less frequent in the asciminib arm vs. the TKI arm.
• The most frequent adverse events in the asciminib arm were low platelet count (13%) and low neutrophil count (10%).
• Asciminib had a lower rate of discontinuation and lower rates of dose adjustment or treatment interruptions.
• Bood clots, a severe side effect of TKIs, were present in only 1% of the participants who took asciminib.

Source:

(2024, May 31). ASCO News Release. Asciminib May Be Safer, More Effective Treatment Option for Patients With Newly Diagnosed Chronic Myeloid Leukemia. New research will be presented at the 2024 American Society of Clinical Oncology (ASCO) Annual Meeting. [Press release]. https://society.asco.org/about-asco/press-center/news-releases/asciminib-may-be-safer-more-effective-treatment-option