BackgroundThe treatment of relapsed/refractory T cell acute lymphoblastic leukemia (R/R T-ALL) is a significant challenge in hematologic oncology, and no standard salvage treatment plan exists. Both Chinese and international clinical guidelines recommend combination chemotherapy including venetoclax.MethodsEfficacy and safety of venetoclax, azacitidine, homoharringtonine, cytarabine, and aclarubicin (VA-HAA) combination therapy were retrospectively analyzed in 3 patients with R/R T-ALL at the Department of Hematology, 920th Hospital of the Joint Logistics Support Force, Chinese People's Liberation Army.ResultsThe chemotherapy resulted in CR/CRi with negative flow MRD in all 3 patients. Quantitative negative conversion was achieved in 2 patients with fusion genes, and the frequency of monoclonal TCR gene rearrangements was significantly reduced in 1 patient. All patients received stem cell rescue after the chemotherapy. Hematologic toxicity may be manageable, with a median of 24 days for complete recovery of neutrophils (ANC) and 36 days for partial recovery of platelets. There were no major bleeding events or chemotherapy-related deaths.ConclusionVA-HAA may be an effective and safe salvage treatment for R/R T-ALL, and prospective clinical trials are needed to verify its specific clinical efficacy.