Journal Article

A phase 2 study of polatuzumab vedotin + bendamustine + rituximab in relapsed/refractory diffuse large B‐cell lymphoma

Kato, Koji, Suehiro, Youko, Hashizume, Misato, Goto, Hideki, Kumagai, Kyoya, Terui, Yasuhito, Takizawa, Jun, Fukuhara, Noriko, Kanemura, Nobuhiro, Kawasaki, Atsuko, Yamaguchi, Motoko, Ishikawa, Takayuki, Kuroda, Junya, Shibayama, Hirohiko, Ishizawa, Kenichi, Saito, Tomohisa, Ueda, Yasunori, Yamamoto, Kazuhito, Izutsu, Koji, Rai, Shinya, Ohmine, Ken

2021

Overview

Polatuzumab vedotin (pola) is a CD79b‐targeted antibody‐drug conjugate delivering a potent antimitotic agent (monomethyl auristatin E) to B cells. This was an open‐label, single‐arm study of pola 1.8 mg/kg, bendamustine 90 mg/m2, rituximab 375 mg/m2 (pola + BR) Q3W for up to six cycles in patients with relapsed/refractory (R/R) diffuse large B‐cell lymphoma (DLBCL) who received ≥1 prior line of therapy and were ineligible for autologous stem cell transplantation (ASCT) or experienced treatment failure with prior ASCT. Primary endpoint was complete response rate (CRR) at the end of the treatment (EOT) by positron emission tomography–computed tomography (PET‐CT) using modified Lugano Response Criteria. Secondary endpoints included efficacy, safety, and pharmacokinetics. Thirty‐five patients (median age 71 [range 46‐86] years) were enrolled. Twenty‐three (66%) patients had refractory disease, and 23 (66%) had ≥2 prior lines of therapy. At a median follow‐up of 5.4 (0.7‐11.9) months, patients received a median of five treatment cycles. CRR was 34.3% (95% confidence interval [CI] 19.1‐52.2) at EOT. Overall response rate was 42.9% at EOT, and median progression‐free survival was 5.2 months (95% CI 3.6‐not evaluable). Median overall survival was not reached. No fatal adverse events (AEs) were observed. Grade 3‐4 AEs were mainly hematological: anemia (37%), neutropenia (31%), white blood cell count decreased (23%), thrombocytopenia/platelet count decreased/neutrophil count decreased (20% each), and febrile neutropenia (11%). Grade 1‐2 peripheral neuropathy (PN; sensory and/or motor) was reported in 14% of patients; there were no ≥grade 3 PN events. This study (JapicCTI‐184048) demonstrated the efficacy and safety of pola + BR in Japanese patients with R/R DLBCL who were ineligible for ASCT. We report the results of an open‐label, single‐arm study of polatuzumab vedotin 1.8 mg/kg, bendamustine 90 mg/m2, rituximab 375 mg/m2 in patients with transplant‐ineligible relapsed/refractory (R/R) diffuse large B‐cell lymphoma (DLBCL). A complete response rate of 34.3% at the end of the treatment and consistent safety profile with previous studies with polatuzumab vedotin were observed.

• Publisher: John Wiley & Sons, Inc,John Wiley and Sons Inc
• Subject: Adverse events / Antibodies / Autografts / B cells / B-cell lymphoma / Bendamustine / Computed tomography / diffuse large B‐cell lymphoma / Drug dosages / Granulocytes / Laboratories / Leukocytes (neutrophilic) / Lymphocytes B / Lymphoma / Lymphomas / Medical prognosis / Neutropenia / Original / Patients / Peripheral neuropathy / PET imaging / Pharmacokinetics / polatuzumab vedotin / Positron emission tomography / relapsed/refractory (R/R) / Response rates / Rituximab / Stem cell transplantation / Stem cells / Thrombocytopenia / Transplantation / Transplants & implants / Vincristine