Chidamide with PEL regimen (prednisone, etoposide, lenalidomide) for elderly or frail patients with relapsed/refractory diffuse large B-Cell lymphoma -results of a single center, retrospective cohort in China

Treatment for relapsed/refractory Diffuse Large B-Cell Lymphoma (R/R DLBCL) is evolving rapidly due to the emergence of novel drugs, of which histone deacetylase inhibitors (HDACis) are an important example. This study showed efficacy in patients with R/R DLBCL after failure of conventional therapies. We conducted a single-center, retrospective study of 34 frail or elderly R/R DLBCL patients who had been treated off-label with chidamide-containing regimens from 2018 to 2020. X² or Fisher test were used to compare response rate and Kaplan-Meier method was used to perform the survival analyses which compared with log-rank test between different groups. The test standard was p < 0.05. In total, 34 patients with R/R DLBCL received CPEL+/-R for at least 1 cycle were included. Most of them were refractory patients (n = 28,82.4%). The interim objective response rate (ORR) was 73.5% (32.4% complete remission [CR]), and the ultimate ORR was 50.0% (35.3% CR). After a median follow-up of 13.1 months, the median progression-free survival (PFS) was 10.5 months (95%CI 6.4-14.6) and the median overall survival (OS) was 19.3 months (95%CI 11.8-26.9). The 1 year expected PFS and OS rate was 43.0% and 73.7%, respectively. The most common grade 3/4 hematologic adverse events (AEs) were neutropenia (n = 11,32.3%) and anemia (n = 4, 11.8%) 0.23.5% (8/34) of all patients experienced grade 3/4 nonhematologic AEs. No treatment-related deaths were observed. The study showed chidamide-included regimen could be an option for R/R DLBCL patients ineligible for intensive chemotherapies. Current data showed favorable efficiency and moderate safety profile. Further study is warranted for better illustration of efficacy and usage in combination therapies.