Study of APG-2575 as a Single Agent or in Combination With Other Therapeutic Agents for CLL/SLL

The study will be conducted in two (2) parts and each part will consist of a ramp-up period, dose escalation and dose expansion portions. The duration of the ramp-up period will depend on the dose schedule being tested and will be conducted for both monotherapy and combination therapy. The ramp-up will consist of treatment with lisaftoclax given once a day starting at 20 mg on Day 1, 50 mg on Day 2, 100 mg on Day 3, 200 mg on Day 4, 400 mg on Day 5¸ 600 mg on Day 6, 800 mg on Day 7, and 1,000 mg on Day 8. Scheduled maximum cohort doses for evaluation will start at 400 mg of lisaftoclax to a maximum of 1000 mg of lisaftoclax. Consequently, patients with a scheduled maximum dose of 200 mg will have a 3-day ramp-up period, those scheduled at 400 mg, a 4-day ramp-up, and those scheduled at 600 mg, a 5-day ramp-up, etc, see Figure 1. Part 1 will study lisaftoclax at different dose levels including 400 mg, 600 mg, 800 mg, and 1,000 mg as monotherapy with dose expansion at RP2D. Part 2 will be combination of lisaftoclax with rituximab or acalabrutinib. Part 2 will be a 3+3 dose escalation of combination lisaftoclax plus rituximab or acalabrutinib. Expansion cohorts at RP2D for the respective combinations will be conducted to further evaluate safety and anticancer activity