Inclusion Criteria:
* Combination Cohort A: Part A (dose exploration): Age ≥18 years; no requirement for transplant ineligibility. Part B (efficacy exploration): Age ≥65 years, or 60 to \<65 years with ≥1 of the following criteria for autologous stem cell transplantation (auto-SCT) ineligibility:① left ventricular ejection fraction (LVEF) ≤45%;② creatinine clearance (CrCl) 30-\<70 mL/min;③ diffusing capacity of the lung for carbon monoxide (DLCO) ≤60% predicted;④ Eastern Cooperative Oncology Group performance status (ECOG PS) 2;⑤ cumulative illness rating scale (CIRS) total score \>6;⑥ other comorbidities precluding intensive induction chemotherapy and transplantation, as assessed by the investigator;
* Combination Cohorts B and C: Age ≥18 years;
* Histologically confirmed MCL, CD20-positive, with documented high Cyclin D1 expression by immunohistochemistry (IHC) and/or positive t(11;14) by cytogenetics;
* Ann Arbor clinical stage II-IV;
* Part A (Dose exploration): ≥1 prior line of therapy, relapsed/refractory disease, no prior BTK inhibitor, and ≤3 total prior lines.Part B (Efficacy exploration): No prior systemic therapy for MCL;
* At least one measurable lesion;
* ECOG performance status 0-2;
* Adequate organ function within 7 days before first dose;
* Women of childbearing potential: negative pregnancy test before treatment and effective contraception during the study and for 6 months after the last dose; male participants: effective contraception during the same period;
* Written informed consent obtained before study participation.
Exclusion Criteria:
* Participants whose treatment intent is tumor debulking prior to stem cell transplantation;
* Active central nervous system (CNS) involvement by lymphoma, leptomeningeal disease, or history of spinal cord compression;
* Severe cardiovascular disease within 6 months prior to screening;
* Any active major infection (e.g., bacterial, viral, or fungal), including CMV DNA PCR-positive participants;
* Serological evidence of active hepatitis B or hepatitis C infection;
* Known history of human immunodeficiency virus (HIV) infection;
* History of stroke or intracranial hemorrhage within 6 months before first dose of study drug;
* History of bleeding diathesis (e.g., hemophilia, von Willebrand disease); requiring or currently receiving anticoagulation with warfarin or equivalent vitamin K antagonists;
* Requires strong CYP3A4 inhibitors or inducers. Strong CYP3A4 inhibitors within 1 week or strong CYP3A4 inducers within 3 weeks before first dose of study drug are prohibited;
* Concurrent or prior malignancy, except adequately treated basal cell or squamous cell skin cancer, cervical carcinoma in situ, or other cancers with no disease progression for ≥2 years;
* Malabsorption syndrome or significant gastrointestinal dysfunction (e.g., gastrectomy, small bowel resection, symptomatic inflammatory bowel disease, complete/incomplete intestinal obstruction).
