Survivin antisense oligonucleotide is efficacious in ALL xenografts. NOD/severe combined immunodeficiencymice were xenografted with human ALL from patient samples. After establishment of disease, defined as greater than 5% blasts detected in peripheral blood, mice were randomized to treatment. Disease was evaluated at weekly intervals by flow cytometric analysis of peripheral blood detecting human CD19 + and CD45 + cells. Graphs depict mean absolute peripheral blood blast counts (white blood cells × % blasts by FACS analysis) from mice. Error bars depict standard error of mean. (a) Treatment with 25 mg/kg of EZN-3042 3 days a week (Monday, Wednusday and Friday) vs scrambled control EZN-3046 generated from the four patient samples at weekly intervals, demonstrating statistically significant difference (P<0.05) in two of four samples. (b) Determination of survivin mRNA expression in the spleen and bone marrow samples after 14 days of treatment with EZN-3042. Data graphed relative to expression in presence of control LNA-ON, corrected for B2-microglobulin levels. (c) Treatment of xenograft 240 with antisurvivin EZN-3042, methotrexate (MTX), temsirolimus (CCI) or triptolide vs untreated control. Graphs represent data collected at subsequent weeks normalized to starting mean absolute blast counts. Drug doses: EZN-3042 25 mg/kg 3 days a week (Monday, Wednesday and Friday); methotrexate 5–10 mg/kg weekly; CCI 5 mg/kg daily; triptolide 0.15 mg/kg/day IP. All chemotherapeutic drugs were administered intraperitoneally and each treatment:control combination was performed as a separate experiment.