Updated Analysis of Obinutuzumab in Rituximab-Refractory Indolent Non-Hodgkin Lymphoma


Key Points

  • The obinutuzumab/bendamustine group had significantly prolonged progression-free survival, both overall and among patients with follicular lymphoma.
  • Overall survival was also significantly improved among all patients and in the follicular lymphoma subgroup.

As reported in the Journal of Clinical Oncology by Cheson et al, an updated analysis of the phase III GADOLIN trial showed an overall survival advantage with obinutuzumab (Gazyva) plus bendamustine induction followed by obinutuzumab maintenance vs bendamustine alone in patients with rituximab (Rituxan)-refractory indolent non-Hodgkin lymphoma.

The GADOLIN trial supported the 2016 approval of obinutuzumab for use in previously treated follicular lymphoma.

Study Details

In the trial, 413 patients were randomized to receive induction with obinutuzumab plus bendamustine (n = 204; 164 with follicular lymphoma) or bendamustine (n = 209; 171 with follicular lymphoma), with patients who had no disease progression on obinutuzumab/bendamustine receiving obinutuzumab maintenance for up to 2 years.

The primary endpoint was progression-free survival. The primary analysis from the trial showed a significant improvement in progression-free survival in the obinutuzumab/bendamustine group. At the time of analysis, overall survival data were not mature.

Updated Analysis

In the updated analysis, median follow-up was 31.8 months. Median progression-free survival among all patients was 25.8 months in the combination group vs 14.1 months in the bendamustine group (hazard ratio [HR] = 0.57, P < .001). Median overall survival was not estimable in either group; 25.5% vs 34.9% of patients had died (HR = 0.67, P = .0269). Among patients with follicular lymphoma, median progression-free survival was 25.3 vs 14.0 months (HR = 0.52, P < .001); median overall survival was not estimable vs 53.9 months (HR = 0.58, P = .0061).

Adverse Events

Grade ≥ 3 adverse events occurred in 72.5% of the obinutuzumab/bendamustine group vs 65.5% of the bendamustine group, with the most common being neutropenia (34.8% vs 27.1%), thrombocytopenia (10.8% vs 15.8%), anemia (7.4% vs 10.8%), and infusion-related reactions (9.3% vs 3.4%). Serious adverse events occurred in 43.6% vs 36.9% of patients. Adverse events led to death in 7.8% vs 6.4% of patients.

The investigators concluded, “This updated analysis confirms the [progression-free survival] benefit for [obinutuzumab/bendamustine] shown in the primary analysis. A substantial [overall survival] benefit also was demonstrated in the [intention-to-treat] population and in patients with [follicular lymphoma]. Toxicity was similar for both treatments.”

The study was supported by F. Hoffmann-La Roche.

Bruce D. Cheson, MD, of Lombardi Comprehensive Cancer Center, Georgetown University Hospital, is the corresponding author for the Journal of Clinical Oncology article.

The content in this post has not been reviewed by the American Society of Clinical Oncology, Inc. (ASCO®) and does not necessarily reflect the ideas and opinions of ASCO®.