Atezolizumab plus R-CHOP appeared to improve CR rates compared with historical controls, but not so much as to warrant further study
Adding atezolizumab to R-CHOP introduced immune-related adverse events, however these did not interfere with the delivery of R-CHOP
Rituximab plus cyclophosphamide, doxorubicin, vincristine and prednisone (R-CHOP) is the current standard therapy for patients with diffuse large B-cell lymphoma (DLBCL) and is curative in ∼60% of patients. Atezolizumab is a humanized immunoglobulin G1 monoclonal antibody that targets programmed death-ligand 1 and has previously shown anti-tumor activity in several tumor types. In a phase 1b/2 trial (NCT02596971) we evaluated the safety and efficacy of atezolizumab in combination with R-CHOP (atezo-R-CHOP; for 6 to 8 cycles) in patients with previously untreated DLBCL. Patients achieving a complete response at the end of induction received consolidation therapy with atezolizumab on Day 1 of each 21-day cycle for an additional 17 cycles. Overall, 42 patients with DLBCL were included in this analysis. The primary endpoint, complete response rate at end of induction, as assessed by an independent review committee (IRC; modified Lugano 2014) was 77.5% (95% confidence interval [CI], 64.0-87.7; n = 40). Investigator-assessed progression-free survival and overall survival at 3 years were 77.4% (95% CI, 59.7-88.0) and 87.2% (95% CI, 71.9-94.5), respectively. All treated patients experienced ≥1 adverse event (AE; 32 patients [76.2%] had a Grade 3-4 AE). One patient had a fatal AE (unconfirmed progressive multifocal leukoencephalopathy), that was considered related to atezolizumab and rituximab, and 17 (40.5%) patients experienced atezolizumab-related AEs of special interest. In previously untreated patients with DLBCL, atezo-R-CHOP demonstrated encouraging clinical efficacy and a safety profile consistent with the known toxicities of the individual drugs.