Polatuzumab Vedotin Combo Improves Outcomes in Previously Untreated DLBCL

A significantly improved and clinically meaningful progression-free survival was accomplished by combining polatuzumab vedotin and R-CHOP in patients with previously untreated diffuse large B-cell lymphoma compared with R-CHOP alone, according to results of the phase 3 POLARIX trial.

A significantly and clinically meaningful improvement in progression-free survival (PFS) was accomplished by combining polatuzumab vedotin with rituximab (Rituxan) plus cyclophosphamide, doxorubicin, and prednisone (R-CHOP) n patients with previously untreated diffuse large B-cell lymphoma (DLBCL) compared with R-CHOP, according to results of the phase 3 POLARIX trial announced in a press release from Roche.1

The safety profile of polatuzumab vedotin in the study has thus far shown consistency with previous clinical trials. Roche announced that results from POLARIX (NCT03274492) will be presented at an upcoming medical meeting and submitted to health authorities.

“Since 40% of people with DLBCL relapse after initial therapy, achieving meaningful treatment effects in the front-line setting has the potential to be transformative,” said Levi Garraway, MD, PhD, chief medical officer and head of Global Product Development, in a press release. “This Polivy regimen is the first in two decades to improve progression-free survival in DLBCL compared to the standard of care, and we look forward to sharing these results with health authorities to bring this important potential new treatment option to patients as soon as possible.”

POLARIX is a multicenter, randomized, double-blind, placebo-controlled trial of approximately 1000 patients with previously untreated DLBCL. Those dosed in the study’s experimental arm received polatuzumab vedotin at 1.8 mg/kg intravenously (IV) with placebo for vincristine IV, rituximab 375 mg/m2 IV, cyclophosphamide 750 mg/m2 IV, and doxorubicin 50 mg/m2 IV on day 1. Then, on days 1-5 of every 21-day cycle, they also receive prednisone at 100 mg/day) orally for 6 cycles.1,2

In the comparator arm, patients receive placebo for polatuzumab vedotin in combination with rituximab 375 mg/m2 IV, cyclophosphamide 750 mg/m2 IV, doxorubicin 50 mg/m2 IV, and vincristine 1.4 mg/m2 IV on day 1 along with prednisone 100 mg/day orally on days 1-5 of every 21-day cycle for 6 cycles.2

The primary end point of the study is PFS, and the secondary end points include the percentage of patients with a complete response to therapy, event-free survival, overall survival, disease-free survival, and other efficacy and safety end points.

To be eligible for inclusion in the stud,y patients were required to be diagnosed with previously untreated DLBCL, and have an International Prognostic Index of 2-5, an ECOG performance status of 0-2, a life expectancy of at least 12 months, left ventricular fraction > 50%, and adequate hematologic function.

Polatuzumab vedotin is used in the relapsed or refractory setting of DLBCL as an off-the-shelf, fixed-duration therapy. It is FDA-approved in combination with bendamustine and rituximab for the treatment of adults with relapsed/refractory who have received at least 2 prior therapies. Approval was granted to the combination for this indication based on results from the study GO29365 (NCT02257567), in which the combination achieved a 58% reduction in the risk of death compared with bendamustine and rituximab alone in patients with relapsed/refractory DLBCL.

The POLARIX study was launched to further explore the efficacy and safety of polatuzumab vedotin in an earlier treatment setting. The study is ongoing in 247 locations across the United States, Canada, Europe Australia, and Asia.

References:

1. [Ad hoc announcement pursuant to Art. 53 LR] Phase III study shows Roche's Polivy plus R-CHP is the first regimen in 20 years to significantly improve outcomes in previously untreated aggressive form of lymphoma compared to standard of care. News release. August 9, 2021. Accessed August 9, 2021. https://bit.ly/37uW6Zm

2. A Study comparing the efficacy and safety of polatuzumab vedotin with rituximab-cyclophosphamide, doxorubicin, and prednisone (R-CHP) versus rituximab-cyclophosphamide, doxorubicin, vincristine, and prednisone (R-CHOP) in participants with diffuse large b-cell lymphoma (POLARIX). Clinicaltrials.gov. Accessed August 9, 2021.