Efficacy and safety of polatuzumab vedotin–based regimens in newly diagnosed diffuse large B-cell lymphoma: A single-center retrospective study

Abstract

Abstract Objective To evaluate the efficacy and safety of polatuzumab vedotin (Pola)–based regimens in newly diagnosed diffuse large B-cell lymphoma (DLBCL) patients, with a focus on the performance of the Pola-R-CHP regimen in different subtypes and high-risk populations. Methods We retrospectively analyzed the clinical data of 42 newly diagnosed DLBCL patients treated with Pola-based regimens at our center between January 2023 and May 2025. Treatment regimens included Pola-R-CHP (rituximab, cyclophosphamide, doxorubicin, prednisone) in 30 patients, Pola-miniCHP in 4 patients, Pola-ZR (zanubrutinib, rituximab) in 6 patients, and other regimens in 2 patients. Baseline clinical characteristics, overall response rate (ORR), complete response (CR) rate, subgroup outcomes, survival, and adverse events were collected. Response assessment was based on whole-body PET-CT or contrast-enhanced CT, and adverse events were graded according to CTCAE version 5.0. Results Among 42 patients, 47.6% were male and 52.4% female, with a median age of 61 years (range, 18–81). Non-GCB subtype accounted for 73.8%, double-expressor lymphoma (DEL) for 28.6%, extranodal involvement for 90.5%, and IPI score 3–5 for 61.9%. Median follow-up was 182 days (range, 57–731). The ORR for all Pola-based regimens was 90.5%, with a CR rate of 71.4%, partial response (PR) rate of 19.1%, and progressive disease (PD) rate of 9.5%. Estimated 1-year overall survival (OS) and progression-free survival (PFS) rates were 92.9% and 88.1%, respectively. No statistically significant differences in ORR or CR rates were observed among clinical subgroups. By regimen, Pola-R-CHP achieved an ORR of 93.3% and CR rate of 76.7%; Pola-miniCHP, 100.0% and 50.0%; and Pola-ZR, 83.3% and 66.7%, respectively. Combined analysis of Pola-miniCHP and Pola-ZR (mainly for elderly, frail, or chemotherapy-intolerant patients) yielded an ORR of 90.0% and CR rate of 60.0%. In the Pola-R-CHP cohort (n=30), ORR was 93.3%, CR 76.7%, PR 16.7%, and PD 6.7%. DEL vs. non-DEL patients had ORRs of 85.7% and 95.7%, and CR rates of 71.4% and 78.3%, respectively. IPI 0–2 vs. 3–5 had ORRs of 100.0% and 88.2%, and CR rates of 84.6% and 70.6%. Patients with <2 vs. ≥2 extranodal sites had ORRs of 100.0% and 88.2%, and CR rates of 92.3% and 64.7%. Estimated 1-year OS and PFS were 94.4% and 89.4%, respectively. The most common hematologic toxicities were anemia (grade 1–2, 59.5%; grade 3–4, 9.5%), neutropenia (16.7%; 21.4%), and leukopenia (33.3%; 21.4%). The most common non-hematologic toxicity was pneumonia (26.2%). In the Pola-R-CHP group, anemia occurred in 53.3% (grade 1–2) and 10.0% (grade 3–4); leukopenia in 23.3% and 23.3%; neutropenia in 10.0% and 13.3%; and pneumonia in 23.3%. Conclusion In real-world practice, Pola-based regimens demonstrated high response rates and favorable tolerability in newly diagnosed DLBCL patients. Pola-R-CHP, as the predominant frontline regimen, showed consistent efficacy and manageable safety in high-risk subgroups including non-GCB, DEL, high IPI scores, and multiple extranodal involvement. Dose-reduced chemoimmunotherapy (Pola-miniCHP) and chemo-light regimens (Pola-ZR) provided reasonable efficacy in elderly or frail patients, warranting further evaluation in larger cohorts. Keywords polatuzumab vedotin; diffuse large B-cell lymphoma; newly diagnosed; efficacy; safety