Polatuzumab vedotin-based salvage immunochemotherapy as third-line or beyond treatment for patients with diffuse...

Polatuzumab vedotin (PoV) has recently shown promising activity when combined with rituximab-bendamustine (BR) in patients with relapsed/refractory (R/R) diffuse large B-cell lymphoma (DLBCL). However, few studies have described the prognostic factors predicting response. Here, we aimed to evaluate the efficacy and safety profile of PoV-based chemotherapy, including regimens other than BR, as third-line or beyond treatment for patients with R/R DLBCL and to explore prognostic factors. Overall, 40 patients, including 37 with de novo and 3 with transformed DLBCL, were enrolled. The overall response rate was 52.5%, and 25% and 27.5% of patients showed a complete response and partial response, respectively. With a median follow-up of 18.8 months, the median overall survival (OS) of the total cohort was 8.5 months, and that of those receiving subsequent hematopoietic stem cell transplantation (HSCT) was 24 months. Low/intermediate risk according to the revised International Prognostic Index score at diagnosis and before PoV treatment predicted better OS. Furthermore, a normal lactate dehydrogenase level and an absolute lymphocyte count/absolute monocyte count ratio > 1.5 were favorable OS prognostic factors. The most common adverse event was cytopenia, with 42.5% of patients developing febrile neutropenia. Grade 1-3 peripheral neuropathy associated with PoV was reported in 25% of patients and resolved in most patients after the cessation of treatment. In summary, we demonstrated that PoV combined with either BR or other intensive chemotherapy is an effective and well-tolerated salvage option for patients with R/R DLBCL. Subsequent HSCT has the potential to further improve survival outcomes in this high-risk population. Clinicaltrials.gov number: NCT05006534.