Pomalidomide Plus Anti-CD20 Antibody and Prednisone in Frontline Indolent B-Cell Lymphoma

A Phase II Study of Pomalidomide Combined with Anti-CD20 Monoclonal Antibody and Prednisone in Frontline Indolent B-Cell Lymphoma Objective: This prospective, single-arm, Phase II trial aims to evaluate the efficacy and safety of first-line pomalidomide plus anti-CD20 antibody and prednisone in patients with indolent B-cell lymphoma.

Study Population: Approximately 30 adult patients (age ≥18 years) will be enrolled. Eligible histologies include follicular lymphoma (FL), CD20-positive marginal zone lymphoma (MZL: extranodal MALT, splenic SMZL, nodal NMZL), indolent mantle cell lymphoma (MCL), chronic lymphocytic leukemia/small lymphocytic lymphoma (CLL/SLL), and lymphoplasmacytic lymphoma/Waldenström macroglobulinemia. Patients must be treatment-naïve, have an indication for systemic therapy, ECOG performance status 0-2, and adequate bone marrow reserve (ANC ≥1.5×10⁹/L, platelets ≥75×10⁹/L, hemoglobin ≥9.0 g/dL; lower thresholds permitted if marrow/spleen involvement, per investigator discretion). Adequate organ function is required: bilirubin ≤2×ULN, ALT/AST ≤2.5×ULN, and creatinine clearance >30 mL/min. Life expectancy must be ≥3 months, and written informed consent is mandatory.

Exclusion Criteria: Patients are excluded if they have another malignancy within 5 years (unless curatively treated without recurrence), CNS lymphoma involvement, transformation to high-grade lymphoma, uncontrolled infection, severe comorbidities affecting study participation, significant non-lymphoma-related organ dysfunction (ALT/AST >3×ULN, bilirubin >2×ULN, creatinine >1.5×ULN), active CNS dysfunction, major surgery within 30 days, pregnancy or lactation, lack of contraception in women of childbearing potential, known drug hypersensitivity, or any condition deemed unsuitable by the investigator.

Treatment Regimen: Induction consists of six 28-day cycles. Anti-CD20 antibody is administered at 375 mg/m² weekly during Cycle 1 and on Day 1 of Cycles 2-6. Pomalidomide is given at 4 mg/day on Days 2-22 of Cycles 1-6. Prednisone is administered at 100 mg/day on Days 1-5 of Cycles 1-6. Maintenance therapy continues for 2 years with pomalidomide 4 mg/day on Days 1-14 and anti-CD20 antibody 375 mg/m² on Day 1 every 8 weeks.

Endpoints: The primary endpoint is overall response rate (ORR). Secondary endpoints include complete response rate (CR), progression-free survival (PFS), overall survival (OS), and safety (hematologic and non-hematologic adverse events).

Statistical Methods: Continuous variables will be summarized with descriptive statistics; categorical variables with frequencies and percentages. Time-to-event endpoints (PFS, OS, and duration of response) will be analyzed using the Kaplan-Meier method, reporting medians, quartiles, and 90% confidence intervals, along with event and censoring counts. ORR will be tested statistically and reported with a 90% confidence interval.

Timeline: The study is expected to begin in January 2026, complete enrollment by December 2026, and conclude by December 2027. The total planned sample size is 30 patients.