Venetoclax Plus Blinatumoma as First Line Therapy for Newly Diagnosed Ph-Negative B-Cell Acute Lymphoblastic Leukemia

This study evaluated the efficacy and safety of a 14-day blinatumomab-venetoclax (BV) regimen as induction therapy for newly diagnosed Ph-negative B-cell acute lymphoblastic leukemia (B-ALL), focusing on rapid remission and tolerability in unfit patients.

Thirteen patients received venetoclax (100 mg on day 1, 200 mg on day 2, 300 mg on day 3, and 400 mg from days 4 to 14) with blinatumomab (9 to 28 ug/day) for 14 days. Bone marrow assessments were performed at days 14-21. Primary endpoints were complete remission (CR) rate, minimal residual disease (MRD) negativity by flow cytometry, and adverse events.

The CR rate after one cycle of BV regimen was 92.3% (12/13), and all patients achieved MRD-negativity; 91.7% (11/12) achieved MRD clearance by day 21. Grade 1-2 cytokine release syndrome occurred in 46.2% (6/13; 1 grade 3). Hematologic toxicity included grade 3-4 neutropenia (92.3%) and thrombocytopenia (46.2%), with only 30.8% febrile neutropenia. All AEs resolved rapidly with supportive care, allowing therapy to continue without interruption. At median follow-up of 283 days, 1-year relapse-free survival rate and overall survival rate were 60.6% and 83.3%.

The 14-day BV regimen induced rapid deep remission (91.7% MRD-negative by day 21) with manageable toxicity in Ph-negative B-ALL. Synergistic T-cell activation by venetoclax may explain enhanced efficacy.