Venetoclax with low-dose cytarabine for patients with untreated acute myeloid leukemia ineligible for intensive chemotherapy: results from the Chinese cohort of a phase three randomized placebo-controlled trial

Objective: To investigate the safety and efficacy of venetoclax with low-dose cytarabine (LDAC) in Chinese patients with acute myeloid leukemia (AML) who are unable to tolerate intensive induction chemotherapy.

Methods: Adults ≥ 18 years with newly diagnosed AML who were ineligible for intensive chemotherapy were enrolled in this international, randomized, double-blind, placebo-controlled trial. Globally, patients (n=211) were randomized 2∶1 to either venetoclax with LDAC or placebo with LDAC in 28-d cycles, with LDAC on days 1-10. The primary endpoint was OS; the secondary endpoints included response rates, event-free survival, and adverse events.

Results: A total of 15 Chinese patients were enrolled (venetoclax arm, n=9; placebo arm, n=6) . The median age was 72 years (range, 61-86) . For the primary analysis, the venetoclax arm provided a 38% reduction in death risk compared with the placebo[hazard ratio (HR) , 0.62 (95%CI 0.12-3.07) ]. An unplanned analysis with an additional 6 months of follow-up demonstrated a median OS of 9.0 months for venetoclax compared with 4.1 months for placebo. The complete remission (CR) rates with CR with incomplete blood count recovery (CRi) were 3/9 (33%) and 0/6 (0%) , respectively. The most common non-hematologic adverse effects (venetoclax vs placebo) were hypokalemia[5/9 (56%) vs 4/6 (67%) ], vomiting[4/9 (44%) vs 3/6 (50%) ], constipation[2/9 (22%) vs 4/6 (67%) ], and hypoalbuminemia[1/9 (11%) vs 4/6 (67%) ].

Conclusion: Venetoclax with LDAC demonstrated meaningful efficacy and a manageable safety profile in Chinese patients consistent with the observations from the global VIALE-C population, making it an important treatment option for patients with newly diagnosed AML who are otherwise ineligible for intensive chemotherapy.