Polatuzumab Vedotin in Relapsed or Refractory Diffuse Large B-Cell Lymphoma

Area of Science:

• Hematology
• Oncology
• Immunotherapy

Background:

• Relapsed/refractory diffuse large B-cell lymphoma (DLBCL) presents a therapeutic challenge with limited options for patients ineligible for stem cell transplantation.
• Polatuzumab vedotin, an antibody-drug conjugate targeting CD79b, offers a novel therapeutic strategy.

Purpose of the Study:

• To evaluate the safety and efficacy of polatuzumab vedotin in combination with chemotherapy for R/R DLBCL.
• To compare polatuzumab vedotin plus bendamustine and rituximab (pola-BR) against bendamustine and rituximab (BR) in transplantation-ineligible R/R DLBCL patients.

Main Methods:

• A single-arm cohort assessed safety and efficacy of pola-BG (polatuzumab vedotin, bendamustine, obinutuzumab).
• A randomized cohort compared pola-BR to BR in R/R DLBCL patients ineligible for transplantation.
• Primary endpoint was IRC-assessed complete response (CR) rate; secondary endpoints included duration of response, progression-free survival (PFS), and overall survival (OS).

Main Results:

• Pola-BG demonstrated a tolerable safety profile with a 29.6% CR rate and 10.8 months median OS.
• In the randomized cohort, pola-BR achieved a significantly higher CR rate (40.0% vs 17.5%, P=.026) compared to BR.
• Pola-BR significantly improved median PFS (9.5 vs 3.7 months, P<.001) and median OS (12.4 vs 4.7 months, P=.002) versus BR, despite increased rates of neutropenia, anemia, and thrombocytopenia. Grade 1-2 peripheral neuropathy was common but mostly resolved.

Conclusions:

• Polatuzumab vedotin combined with BR significantly enhances CR rates in transplantation-ineligible R/R DLBCL.
• The addition of polatuzumab vedotin to BR reduces the risk of death by 58% in this patient population.
• Pola-BR represents a more effective treatment option compared to BR for R/R DLBCL patients ineligible for transplantation.