Researchers have evaluated early disease progression and its impact on overall survival ( OS ) in previously untreated follicular lymphoma patients in GALLIUM, and investigated the effect on early disease progression of the two randomization arms: Obinutuzumab-based versus Rituximab-based immunochemotherapy.
Mortality in both groups was analyzed 6, 12, and 18 months post randomization ( median follow up, 41 months ).
Fewer early disease progression events occurred in Obinutuzumab [ Gazyvaro ] ( 57 out of 601 ) versus Rituximab [ MabThera ] ( 98 out of 601 ) immunochemotherapy patients, with an average risk reduction of 46.0% ( 95%CI: 25.0-61.1%; cumulative incidence rate 10.1% vs 17.4% ).
At a median post-progression follow up of 22.6 months, risk of mortality increased markedly following a progression event [ hazard ratio, HR of time-varying progression status, 25.5 ( 95%CI: 16.2-40.3 ) ].
Mortality risk was higher the earlier patients progressed within the first 24 months.
Age-adjusted hazard ratio for overall survival after 24 months in surviving patients with disease progression versus those without was 12.2 ( 95%CI: 5.6-26.5 ).
Post-progression survival was similar by treatment arm.
In conclusion, Obinutuzumab plus chemotherapy was associated with a marked reduction in the rate of early disease progression events relative to Rituximab plus chemotherapy.
Early disease progression in patients with follicular lymphoma was associated with poor prognosis, with mortality risk higher after earlier progression.
Survival post progression did not seem to be influenced by treatment arm. ( Xagena )
Seymour JF et al, Haematologica 2019; 104: 1202-1208