Immunochemotherapy With Obinutuzumab or Rituximab for Previously Untreated Follicular Lymphoma in the GALLIUM Study: Influence of Chemotherapy on Efficacy and Safety.
Hiddemann W., Barbui AM., Canales MA., Cannell PK., Collins GP., Dürig J., Forstpointner R., Herold M., Hertzberg M., Klanova M., Radford J., Seymour JF., Tobinai K., Trotman J., Burciu A., Fingerle-Rowson G., Wolbers M., Nielsen T., Marcus RE.
Purpose The GALLIUM study ( ClinicalTrials.gov identifier: NCT01332968) showed that obinutuzumab (GA101; G) significantly prolonged progression-free survival (PFS) in previously untreated patients with follicular lymphoma relative to rituximab (R) when combined with cyclophosphamide (C), doxorubicin, vincristine (V), and prednisone (P; CHOP); CVP; or bendamustine. This report focuses on the impact of chemotherapy backbone on efficacy and safety. Patients and Methods A total of 1,202 patients with previously untreated follicular lymphoma (grades 1 to 3a), advanced disease (stage III or IV, or stage II with tumor diameter ≥ 7 cm), Eastern Cooperative Oncology Group performance status 0 to 2, and requiring treatment were randomly assigned 1:1 to G 1,000 mg on days 1, 8, and 15 of cycle 1 and day 1 of subsequent cycles or R 375 mg/m2 on day 1 of each cycle, for six to eight cycles, depending on chemotherapy (allocated nonrandomly by center). Responding patients received G or R for 2 years or until disease progression. Results Baseline Follicular Lymphoma International Prognostic Index risk, bulky disease, and comorbidities differed by chemotherapy. After 41.1 months median follow-up, PFS (primary end point) was superior for G plus chemotherapy (overall hazard ratio [HR], 0.68; 95% CI, 0.54 to 0.87; P = .0016), with consistent results across chemotherapy backbones (bendamustine: HR, 0.63; 95% CI, 0.46 to 0.88; CHOP: HR, 0.72; 95% CI, 0.48 to 1.10; CVP: HR, 0.79; 95% CI, 0.42 to 1.47). Grade 3 to 5 adverse events, notably cytopenias, were most frequent with CHOP. Grade 3 to 5 infections and second neoplasms were most frequent with bendamustine, which was associated with marked and prolonged reductions in T-cell counts. Fatal events were more frequent in patients treated with bendamustine, possibly reflecting differences in patient risk profiles. Conclusion Improved PFS was observed for G plus chemotherapy for all three chemotherapy backbones. Safety profiles differed, although comparisons are confounded by nonrandom chemotherapy allocation.