What is Polivy and What Trials Tested It?
Polivy (polatuzumab vedotin-piiq) is an antibody-drug conjugate approved for relapsed or refractory diffuse large B-cell lymphoma (DLBCL). Its key evidence comes from the phase 2 GO29365 trial, which tested it combined with bendamustine and rituximab (BR) versus BR alone in patients who had prior rituximab-containing therapy.[1][2]
Key Results from GO29365 Trial
In the trial of 80 patients (40 per arm), Polivy plus BR showed:
- Median overall survival (OS): 12.4 months versus 4.7 months with BR alone (HR 0.49, 95% CI 0.30-0.80; p=0.002).
- Median progression-free survival (PFS): 7.6 months versus 2.0 months (HR 0.35, 95% CI 0.22-0.57; p<0.0001).
- Objective response rate: 45% versus 18%.[1][2]
These results supported FDA accelerated approval in 2019, converted to full approval in 2023 after confirmatory data.[2]
Confirmatory Phase 3 POLARIX Trial Outcomes
POLARIX tested Polivy plus R-CHP (rituximab, cyclophosphamide, doxorubicin, prednisone) versus R-CHOP as first-line therapy in 880 previously untreated DLBCL patients.
- Co-primary endpoints: PFS met at 2 years (76.7% vs 70.4%; HR 0.73, 95% CI 0.57-0.95; p=0.018), but OS did not reach significance (88.5% vs 88.6%; HR 0.90).[3]
- Event-free survival favored Polivy arm (HR 0.68).[3]
- PET-guided analysis showed deeper responses with Polivy-R-CHP.[3]
This supported expanded approval for first-line use in 2023.[2]
Common Side Effects from Trials
Across GO29365 and POLARIX:
- Most frequent: neutropenia (GO29365: 42%; POLARIX: 60%), thrombocytopenia (42%; 40%), anemia (30%; 30%), peripheral neuropathy (40%; 40%), fatigue (30%; 35%).
- Grade 3-4 events higher with Polivy: neutropenia (42% vs 24% in GO29365), infections (18% vs 13%).
- Discontinuation due to adverse events: 17% in Polivy arms versus 7% for comparators.[1][3]
No new safety signals in frontline setting.[3]
How Does Polivy Compare to Standard Care?
Polivy-BR improved survival over BR in relapsed DLBCL, outperforming historical benchmarks like single-agent options. In frontline POLARIX, it reduced PFS events versus R-CHOP without OS benefit yet, though longer follow-up continues. It offers a chemotherapy-sparing option by dropping vincristine.[1][3]
Sources
[1]: Polivy Prescribing Information (FDA)
[2]: FDA Approval Summary
[3]: POLARIX NEJM Publication