Encouraging Activity of Obinutuzumab (GA101) Monotherapy in Relapsed/Refractory Aggressive Non-Hodgkin's Lymphoma: Results From a Phase II Study (BO20999),

Baseline patient characteristics were similar for both cohorts (Table 1). The median observation time for all patients was 9.5 months (0.3–26.1 months). BOR rates are given in Table 2, with 8/25 diffuse large B-cell lymphoma (DLBCL) patients (32%) and 4/15 mantle cell lymphoma (MCL) patients (27%) responding to GA101. Among the patients with rituximab-refractory disease, a response was observed in 1/13 patients (7.7%) and 4/12 patients (33.3%) treated in the 400/400 mg and 1,600/800 mg cohorts, respectively. Of these, 4 patients (1,600/800 mg cohort) had a response duration > 6 months, with 2 patients having an ongoing response (response duration: 9.8, 16.5+, 19.5 and 20.0+ months). Median PFS for patients with DLBCL (Figure 1) was 1.9 months (range: 0.3–15.7 months) for the 400/400 mg cohort and 2.7 months (range: 0.2–22.3) months) for the 1,600/800 mg cohort (hazard ratio: 0.70; 95% CI: 0.30–1.66). For the DLBCL subgroup, response duration was 3.1, 3.1+, 5.8, 16.5+ and 19.5 months for the 5 responders in the 1,600/800 mg cohort, compared with 6.3, 8.6 and 9.8 months for the 3 responders in the 400/400 mg cohort. Individual response data indicated that 2 MCL patients had an ongoing response for ≥ 20 months (20.0 and 20.4 months). GA101 was well tolerated in both cohorts. Infusion-related reactions (IRRs; all grades) were the most common adverse event (AE), occurring in 81% of patients in the 400/400 mg cohort and 68% of patients in the 1600/800 mg cohort. Grade 3/4 AEs occurring in >5% of patients across both cohorts included IRRs (10%), tumor lysis syndrome (10%), cardiac failure (not treatment-related; 10%), anemia (14%) and thrombocytopenia (14%) in the 400/400 mg cohort and IRRs (5%) and anemia (5%) in the 1,600/800 mg cohort.