Efficacy and Safety of Polatuzumab-Vedotin, Rituximab, Cyclophosphamide, Doxorubicin, and Prednisone (Pola-R-CHP) in Patients with Newly Diagnosed Diffuse Large B-Cell Lymphoma (DLBCL) in the Real-World Setting: A Single Institute Retrospective Analysis
Authors: Otani Atsushi , Ochi Shinichi , Yamamoto Masami , Yamaguchi Shota , Uchihara Masahito , Kobayashi Shinya , Matsumoto Masanori , Yagi Hideo 
Published: December 2024

Background: In POLARIX study, Pola-R-CHP showed significant improvement in progression free survival compared to R-CHOP in previously untreated DLBCL patients aged 18-80 years (2-year PFS: 76.71 % vs 70.20 %, p=0.0177). In September 2022, Pola-R-CHP was approved as first-line treatment for newly diagnosed DLBCL in Japan. However, the efficacy and safety of Pola-R-CHP in real world setting still remain unclear, especially in the patients over 80 years-old. To elucidate the efficacy and safety of Pola-R-CHP in clinical practices, we conducted this single institute retrospective observation study.

Methods: We retrospectively analyzed the patients with newly diagnosed DLBCL who were treated with Pola-R-CHP at Nara Medical General Hospital from December 2022 to October 2023. The dosages of polatuzumab-vedotin and rituximab were not reduced, whereas those of cyclophosphamide, doxorubicin, and prednisone were reduced by each physician decision. The primary endpoint was the response at the end of treatment, and secondary endpoints were 1-year PFS, 1-year OS, and severity and frequency of adverse events.

Results: A total of 39 patients were consecutively enrolled in this study. 22 patients (56.4 %) were female. The median age was 75 (range: 51-88). 12 patients (30.8 %) were older than 80 years-old. 64.1% (25/39) of the patients were classified as Ann Arbor Stage Ⅲ-Ⅳ, and 48.7% (19/39) had IPI (International Prognostic Index) of 3 or more points. 72.4 % (21/29) of patients were GCB (germinal center B-cell) type and 27.6 % (8/29) were non-GCB type (10 patients were not classified). The median number of Pola-R-CHP cycles performed 6 (range, 4-6), with a 6-cycles completion rate of 90 % (27/30). Dosage reduction of cyclophosphamide, doxorubicin, and prednisone were performed in 59.0% (23/39) due to comorbidity and/or frailty, and 100 % (12/12) in elderly patients over 80 years-old (elderly group). Peg-GCF was administered during treatment in 33 patients (84.6 %). The median follow-up was 290 days (range, 115-465 days). The overall response rate (ORR) was 79.5% (31/39), and the rate of achieving complete response (CR) was 59.0 % (n=23), partial response (PR) was 20.5 % (n=8), and progressive disease (PD) was 7.7 % (n=3), respectively. In elderly group, ORR was 91.7 % (11/12). The rate of CR, PR, and PD were 66.7 % (n=8), 25 % (n=3), 8.3 % (n=1), respectively. The PFS at one-year was 68.6% (95% confidence interval (CI), 33.8 %-86.0 %) and the OS at one-year was 76.8% (95 % CI, 44.9 %-91.7 %), respectively. In elderly group, the PFS at one-year was 35.7 % (95% CI, 15 %-77.6 %) and OS at one-year was 81.5 % (95% CI, 43.5 %-95.1 %), respectively. There were no significant differences between patients over and under 80 years-old in PFS (p=0.236) and OS (p=0.607). As safety profiles, grade 3-4 thrombocytopenia, anemia, and neutropenia were observed in 35.9%, 20.5%, and 12.8%, respectively. 6 patients developed febrile neutropenia (FN). Grade 1-2 constipation and peripheral neuropathy was found in 53.8％ and 46.1%, respectively. Grade 3-4 non-hematological AEs occurred in 8 patients, including sepsis, FN, cholangitis, small bowel perforation. Eventually, 5 patients had to discontinue treatment due to AEs. One patient died of sepsis.

Conclusion: In this study, Pola-R-CHP showed favorable treatment response and PFS and OS benefits in patients with previously untreated DLBCL in the real-world setting. Further, AE profiles were similar to those in the POLARIX trial. These results suggested that Pola-R-CHP was feasible and effective in clinical practices including elderly patients with DLBCL.