Abstract

The POLARIX trial demonstrated the superiority of polatuzumab vedotin (Pola) over vincristine in the R-CHOP regimen for large B-cell lymphomas, but it is unknown if Pola can be safely incorporated into intensified regimens (eg. DA-EPOCH-R) typically utilized for the highest risk histologies. This was a single-center, open label, prospective clinical trial of 6 cycles of Pola-DA-EPCH-R in aggressive large B-cell lymphomas. The primary endpoint was to estimate the safety of Pola-DA-EPCH-R as measured by the rate of dose-limiting toxicities (DLTs) in the first 2 cycles with pre-specified suspension rules. Secondary and exploratory endpoints included efficacy and correlation with ctDNA levels. We enrolled 18 patients on study, and with only three DLTs observed, the study met its primary endpoint for safety. There were five serious adverse events including grade 3 febrile neutropenia (3, 17%), grade 3 colonic perforation in the setting of diverticulitis (1, 6%), and grade 5 sepsis/typhlitis (1, 6%). Among 17 evaluable patients, the best overall response rate was 100% and complete response rate of 76%. With median follow up of 12.9 months, 12-month EFS was 72% (95% CI 54-96%) and 12-month OS was 94% (95% CI 84-100%). No patient with undetectable ctDNA at the end of treatment has relapsed to date. Using Pola to replace vincristine in the DA-EPOCH-R regimen met its primary safety endpoint. These data support the further evaluation and use of this approach in histologies where the potential benefit of both an intensified regimen and Pola may be desired.

View details for DOI 10.1182/bloodadvances.2022009145

View details for PubMedID 36521030