LAUSR

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.