CAL-101 induces apoptosis more selectively than pan-PI3K inhibitors. (A) CD19⁺ cells from patients with CLL (n = 49) were incubated with or without 10μM CAL-101 or 25μM LY294002 for 48 hours. Viability was determined by annexin/PI flow cytometry and is shown relative to time-matched untreated controls. Horizontal lines represent the mean. (B) CD19⁺ B cells, CD3⁺ T cells, and CD56⁺ NK cells (n = 10; each) were incubated with or without 10μM CAL-101 and 25μM LY294002 for 48 hours. Viability was determined by annexin/PI flow cytometry and is shown relative to time-matched untreated controls. Error bars represent the SD from the mean.