Obinutuzumab with CHOP therapy did not improve progression-free survival, compared with rituximab plus CHOP, in patients with previously untreated diffuse large B-cell lymphoma (DLBCL), according to results from a phase 3 trial published in the Journal of Clinical Oncology. (2017 Aug 10. doi: 10.1200/JCO.2017.73.3402)
The findings suggest that obinutuzumab, a glycoengineered, type II, anti-CD20 monoclonal antibody, might not offer a benefit over standard treatment with rituximab, an anti-CD20 monoclonal antibody, when used with CHOP (cyclophosphamide, doxorubicin, vincristine, prednisone).
A total of 1,418 patients were enrolled at 207 centers in 29 countries in the GOYA trial and were randomly assigned to one regimen or the other. The mean duration of exposure to the drugs was 25 weeks for both. The progression-free survival was 69.6% for obinutuzumab-CHOP – also known as G-CHOP – and 66.9% for rituximab-CHOP, not a statistically significant difference, wrote Umberto Vitolo, MD, of University-Hospital Città della Salute e della Scienza, Torino, Italy, and his fellow investigators.
The rate of adverse events was similar between the two groups. The lack of superiority of obinutuzumab comes after findings of its superiority in untreated follicular lymphoma (FL) and chronic lymphocytic leukemia (CLL). The investigators suggested that this may be a sign that obinutuzumab’s efficacy is best seen in less aggressive disease types.
“Given the advantages of G-based therapy in patients with FL and CLL, the lack of benefit of G-CHOP in patients with DLBCL in the GOYA study was unexpected, and the reasons for it are unclear,” they wrote. “This lack of benefit might simply have resulted from the differences in biologic and clinical profiles between indolent lymphoproliferative diseases, such as FL and CLL, and aggressive ones, such as DLBCL.”
The study was sponsored by F. Hoffman-La Roche, the manufacturer of the two drugs, and had support from Fondazione Italiana Linfomi.