Zanubrutinib Induction Followed by Delayed Fixed-Duration Combination With Sonrotoclax for CLL/SLL：Stop Trial 2.0

The goal of this clinical trial is to learn if zanubrutinib induction followed by delayed fixed-duration combination with sonrotoclax works to treat previously untreated Chronic Lymphocytic Leukemia (CLL)/Small Lymphocytic Lymphoma (SLL). It will also learn about the safety of this combination regimen. The main questions it aims to answer are:Does this combination therapy achieve undetectable minimal residual disease (uMRD) in participants?What medical problems (adverse events) do participants have when taking zanubrutinib and sonrotoclax?Researchers will conduct a single-arm study to systematically evaluate the MRD clearance, efficacy, safety, and immune-related functions of this specific treatment sequence.Participants will:Low-risk group (without 17p deletion/TP53 mutation): Take zanubrutinib monotherapy for 12 cycles, followed by combination zanubrutinib + sonrotoclax for 12 cycles, then discontinue treatment for observation.High-risk group (with 17p deletion/TP53 mutation): Follow the same initial regimen (12 cycles monotherapy + 12 cycles combination), followed by zanubrutinib monotherapy maintenance until disease progression.Visit the clinic periodically for MRD assessment (via flow cytometry), efficacy evaluation (CT/PET-CT, lab tests), and safety checks (physical exam, blood tests, ECG).Undergo immune function evaluation via peripheral blood samples to assess changes in T-cell counts and subsets.