Marcus R, et al. - A comparison was performed of rituximab-based chemotherapy with obinutuzumab-based chemotherapy in patients with previously untreated advanced-stage follicular lymphoma. Findings revealed a longer progression-free survival with obinutuzumab-based immunochemotherapy and maintenance therapy in comparison to rituximab-based therapy. However, obinutuzumab-based chemotherapy resulted in high-grade adverse events more commonly.

Methods

• Patients were randomly assigned to recieve induction treatment with obinutuzumab-based chemotherapy or rituximab-based chemotherapy.
• For up to 2 years, patients with a response received maintenance treatment with the same antibody that they had received in induction.
• Investigator-assessed progression-free survival was observed as the primary end point.

Results

• Randomization was performed of 1202 patients with follicular lymphoma (601 patients in each group).
• A planned interim analysis, after a median follow-up of 34.5 months (range, 0 to 54.5), indicated that obinutuzumab-based chemotherapy resulted in a markedly lower risk of progression, relapse, or death than rituximab-based chemotherapy (estimated 3-year rate of progression-free survival, 80.0% vs. 73.3%; hazard ratio for progression, relapse, or death, 0.66; 95% confidence interval [CI], 0.51 to 0.85; P=0.001).
• There appeared similar results regarding independently reviewed progression-free survival and other time-to-event end points.
• Response rates were similar in the two groups (88.5% in the obinutuzumab group and 86.9% in the rituximab group).
• In the obinutuzumab group, adverse events of grade 3 to 5 were more frequent than in the rituximab group (74.6% vs. 67.8%), as were serious adverse events (46.1% vs. 39.9%).
• The two groups were similar in terms of rates of adverse events resulting in death (4.0% in the obinutuzumab group and 3.4% in the rituximab group).
• Infusion-related events were the most common adverse events that were considered by the investigators to be largely due to obinutuzumab in 353 of 595 patients (59.3%; 95% CI, 55.3 to 63.2) and to rituximab in 292 of 597 patients (48.9%; 95% CI, 44.9 to 52.9; P<0.001).
• They observed common occurrence of nausea and neutropenia.
• In the obinutuzumab group, 35 patients (5.8%) and in the rituximab group, 46 (7.7%) patients died.