Obinutuzumab/polatuzumab in follicular lymphoma

Prof. Wojciech Jurczak (Jagiellonian University, Poland) presented the history of trials in high-risk relapsed/refractory follicular lymphoma (FL), focussing on a pre-planned interim analysis of a recent phase 1b/2 study [1,2].

This open-label, single-arm trial assessed the safety and preliminary efficacy of polatuzumab vedotin in combination with obinutuzumab and lenalidomide (Pola-G-Len) in patients with relapsed/refractory FL (n=52). Polatuzumab vedotin is a first-in-class antibody-drug conjugate that targets CD76b, a protein expressed in FL and diffuse large B cell lymphoma (DLBCL). Polatuzumab vedotin in combination with rituximab and bendamustine was recently approved for the treatment of relapsed or refractory DLBCL.

The primary efficacy endpoint of the trial was complete response (CR) at the end of induction treatment, as assessed by an independent review committee based on PET-CT scans. Patients received Pola-G-Len induction treatment (six 28-day cycles). At a median follow-up of 16.6 months (range 3.2-25.1), the median progression-free survival (PFS) had not been reached, with a 12-month PFS rate of 90%. Two out of 17 responders have experienced progressive disease; the remaining patients have ongoing responses (longest one > 21 months).

No new safety signals were recorded, overall safety was comparable with previous reports in DLBCL. A grade 3 or higher neutropenia was reported in 30% of patients; 18% were febrile, and 9% had thrombocytopenia. Treatment was discontinued by 11% of patients due to AEs after receiving 1–5 cycles, and 8% of patients had a pola dose reduction. The results of this phase 1b-2 trial indicate Pola-G-Len treatment has a manageable toxicity profile and leads to promising response outcomes in relapsed/refractory follicular lymphoma.

1. 1. Jurczak W. 24th Congress of the EHA, 13-16 June 2019, Amsterdam, the Netherlands.
   2. Diefenbach, C. et al. Abstract 7505, 2019 ASCO Annual Meeting, Chicago, Illinois, USA.

 

Posted on 9 August, 201919 November, 2021