Ian W. Flinn, MD, PhD, discusses the study design and results of the phase 2 trial of the antibody-drug conjugate polatuzumab vedotin-piiq plus bendamustine and rituximab for patients with relapsed/refractory diffuse large B-cell lymphoma.
Ian W. Flinn, MD, PhD, director of lymphoma research at Sarah Cannon Cancer Institute, discusses the study design and results of the phase 2 trial (NCT02257567) of the antibody-drug conjugate polatuzumab vedotin-piiq (Polivy) plus bendamustine and rituximab (Rituxan) for patients with relapsed/refractory diffuse large B-cell lymphoma (R/R DLBCL).
In cohorts C and D of this trial, 80 patients were randomized 1:1 to receive either 1.8 mg/kg of polatuzumab every 3 weeks plus bendamustine and rituximab for 6 cycles, or only bendamustine and rituximab. The primary end point was complete response (CR) rate as assessed by an independent review committee.
The primary end point was met, with a CR rate in the polatuzumab arm of 40%, versus 17.5% in those receiving only bendamustine/rituximab. At a median follow-up of 22.3 months, the polatuzumab arm had a median progression-free survival (PFS) of 9.5 months versus 3.7 months in the other arm (HR, 0.36; 95% CI, 0.21-0.63; P < .001). Median overall survival (OS) was 12.4 months with polatuzumab versus 4.7 months with only bendamustine/rituximab (HR, 0.42; 95% CI, 0.24-0.75; P = .002).
Flinn says these are impressive results considering that patients had a median of 2 prior lines of therapy. This trial led to the approval of polatuzumab vedotin plus bendamustine/rituximab as third-line therapy for R/R DLBCL.
TRANSCRIPTION:
0:08 | This was the study of polatuzumab vedotin with bendamustine and rituximab. There are several different arms of this trial, but the pivotal arm was a randomized phase 2 trial that had a 1:1 randomization for patients who had previously treated DLBCL that had relapsed/refractory patients. There were 80 patients on this trial; patients are randomized 1:1 to receive [bendamustine/rituximab] plus or minus polatuzumab. And the primary end point of this study was CR rate.
0:45 | The basic results of this study were that 40% of patients achieved a CR rate with a CR with polatuzumab/BR versus 17.5% of patients who are on the [bendamustine/rituximab]-alone arm, and…that met the primary end point of the study which was a higher CR rate as judged by an independent response committee. The other end points of the study were PFS and OS. And there was a substantial improvement in PFS for those patients treated on the experimental arm, it was 9.5 months versus 3.7 months.
1:29 | And then the OS was also surprisingly much improved with those patients who received the polatuzumab-containing arm. I say surprisingly, because this was third line, and the magnitude of difference was pretty large; it was 12.4 months versus 4.7 months. And when you think about it, this is not very many patients, just 40 patients per arm. To me, this was very spectacular results.
TMLI Trial Shows Potential in Relapsed/Refractory Leukemia
October 2nd 2024In an interview, Jeffrey Wong, MD, and Anthony Stein, MD, provided an in-depth discussion on a phase 2 trial of total marrow and lymphoid irradiation with cyclophosphamide and etoposide in high-risk acute leukemia.
Read More