Alternating Regimen of VA and Low-dose CHA in the Treatment of Unfit Newly Diagnosed AML

"1. Induction Phase (4 alternating cycles):~ Participants will receive 4 cycles of alternating therapy:~ * VA Cycle:~ * Venetoclax 400 mg PO daily on Days 1-28~ * Azacitidine 75 mg/m² SC/IV daily on Days 1-7~ * Low-dose CHA Cycle:~ * Cladribine 5 mg/m² IV daily on Days 1-3~ * Homoharringtonine 1 mg/m² IV daily on Days 1-5~ * Cytarabine 20 mg SC every 12 hours on Days 1-10 Alternating sequence: VA → CHA → VA → CHA → VA → CHA → VA → CHA The interval between the VA to low-CHA is 2 weeks, and the interval between the two alternations (one alternation is VA plus low-CHA）is 4 weeks.~2. Maintenance Phase (24 months):~Following induction, participants will receive:~* Venetoclax 400 mg PO daily on Days 1-28~* Azacitidine 75 mg/m² SC/IV daily on Days 1-7 Repeated every 28 days for 24 cycles. The interval between the two cycles is 2 weeks."