Primary Endpoint in POLARIX Trial
Polivy (polatuzumab vedotin) effectiveness was evaluated in the phase 3 POLARIX trial, which compared Polivy plus BR (rituximab, cyclophosphamide, doxorubicin, prednisone) against BR alone in previously untreated diffuse large B-cell lymphoma (DLBCL) patients. The main measure was progression-free survival (PFS), defined as time from randomization to disease progression, relapse, or death from any cause, assessed per independent review committee using Lugano criteria.[1][2]
Key Secondary Endpoints
- Overall survival (OS): Time from randomization to death from any cause.
- Event-free survival (EFS): Time to disease progression, relapse, death, or inadequate response.
- Complete response (CR) rate: Proportion achieving complete metabolic response via PET-CT scan.
- Duration of response (DOR): Time from response to progression or death.
These used similar independent review standards, with PET-CT for response assessment.[1][3]
Response Assessment Methods
Standardized PET-CT scans (18F-FDG) followed Lugano 2014 classification: complete response required Deauville score 1-3 without residual disease; partial response needed score 4-5 with uptake reduction >50% and no new lesions. CT scans supplemented for extranodal sites. Assessments occurred at end of induction, every 6 months for 2 years, then annually.[1][2]
Statistical Analysis Approach
PFS was tested via stratified log-rank test with O'Brien-Fleming alpha-spending function for interim analyses. Hazard ratios calculated using Cox proportional hazards model, adjusted for stratification factors like International Prognostic Index score and region. Sensitivity analyses confirmed primary results, including investigator-assessed PFS.[1][3]
Patient-Reported and Quality-of-Life Measures
Exploratory endpoints included Functional Assessment of Cancer Therapy-Lymphoma (FACT-Lym) subscale for lymphoma symptoms and EQ-5D-5L for health status, analyzed via repeated-measures mixed models.[2]
Sources
[1] Sehn LH et al. Polatuzumab Vedotin in Previously Untreated Diffuse Large B-Cell Lymphoma. N Engl J Med. 2022;386(2):351-363. Link
[2] POLARIX ClinicalTrials.gov summary. NCT03274492. Link
[3] Polivy prescribing information. Genentech. Link