Orelabrutinib Combined With Rituximab as First-line Systemic Treatment for Marginal Zone Lymphoma

Inclusion Criteria: * Age ≥ 18 years, regardless of gender; * Histologically confirmed CD20-positive marginal zone lymphoma, including MALT, SMZL, and NMZL, with at least one lesion outside the spleen measuring more than 1.5 cm in any axis; * MZL that has progressed or relapsed after prior local therapy (including surgery, radiotherapy, anti-Helicobacter pylori treatment, and anti-hepatitis C treatment), or is not suitable for local therapy; * ECOG performance status of 0-2; * Presence of an indication for treatment as judged by the investigator (symptomatic, cytopenia, risk of end-organ damage, bulky disease, ongoing progression, or patient's desire for treatment); * Adequate function of major organs, as follows: * Hematology: Absolute neutrophil count ≥ 1.5×109/L, platelets ≥ 75×109/L, hemoglobin ≥ 75 g/L; if there is bone marrow involvement, absolute neutrophil count ≥ 1.0×109/L, platelets ≥ 50×109/L, hemoglobin ≥ 50 g/L; * Biochemistry: Total bilirubin ≤ 1.5 times the upper limit of normal (ULN), AST or ALT ≤ 2 times ULN; serum creatinine ≤ 1.5 times ULN; serum amylase ≤ ULN; * Coagulation: International normalized ratio (INR) ≤ 1.5 times ULN. * Life expectancy of ≥ 3 months; * Voluntary written informed consent obtained before screening for the trial. Exclusion Criteria: * Currently or previously having other malignancies, unless there is evidence of no recurrence or metastasis within the past 5 years after curative treatment; * Lymphoma involvement of the central nervous system or transformation to high-grade lymphoma; * Non-hematological toxicities from prior anti-cancer treatments not recovered to ≤ Grade 1 (excluding alopecia); * Presence of uncontrolled or significant cardiovascular disease, including: * New York Heart Association (NYHA) Class II or higher congestive heart failure, unstable angina, myocardial infarction within 6 months before the first administration of the study drug, or arrhythmias requiring treatment at screening, left ventricular ejection fraction (LVEF) \< 50%; * Primary cardiomyopathy (such as dilated cardiomyopathy, hypertrophic cardiomyopathy, arrhythmogenic right ventricular cardiomyopathy, restrictive cardiomyopathy, unclassified cardiomyopathy); * History of clinically significant QTc interval prolongation, or QTc interval \> 470 ms for females, \> 450 ms for males during the screening period; * Symptomatic or medically treated coronary artery disease; * Uncontrolled hypertension (defined as blood pressure not reaching target levels despite a reasonable and tolerable full dose of three or more antihypertensive drugs (including diuretics) for more than one month, or requiring four or more antihypertensive drugs to effectively control blood pressure). * Active bleeding within 2 months before screening, or currently taking anticoagulant drugs, or deemed by the investigator to have a clear tendency to bleed; * Urine protein ≥ 2+, and 24-hour urine protein quantification ≥ 2 g/24 hours; * History of deep vein thrombosis or pulmonary embolism within the past six months; * History of organ transplantation or allogeneic bone marrow transplantation; * Major surgery within 6 weeks before screening or minor surgery within 2 weeks before screening. Major surgery is defined as surgery using general anesthesia, but diagnostic endoscopy is not considered major surgery. Insertion of a vascular access device will be exempt from this exclusion criterion; * Active infection or uncontrolled HBV (HBsAg positive and/or HBcAb positive with positive HBV DNA titer), HCV Ab positive, HIV/AIDS, or other severe infectious diseases; * Currently having pulmonary fibrosis, interstitial pneumonia, pneumoconiosis, radiation pneumonitis, drug-related pneumonia, or other conditions that significantly affect pulmonary function; * Previous treatment with BTK, BCR pathway inhibitors (such as PI3K, Syk), or BCL-2 inhibitors; * Suitable and preparing for stem cell transplantation; * Any psychiatric or cognitive impairment that may limit their understanding, execution of the informed consent form, and compliance with the study; * Subjects with drug abuse or alcoholism; * Pregnant, breastfeeding women, and fertile subjects unwilling to use contraception; * Need to continuously take drugs with moderate to severe inhibitory or strong inducing effects on cytochrome P450 CYP3A; * Any other condition deemed by the investigator as unsuitable for participation in this trial.