Shortened Obinutuzumab Infusion Is Safe and Reduces Chair Time in Frontline Treatment of Chronic Lymphocytic Leukemia: A Real‐World Study

BACKGROUND: Obinutuzumab-based regimens are established frontline treatments for chronic lymphocytic leukemia (CLL), but infusion-related reactions (IRRs) and prolonged administration increase patient burden and outpatient chair occupancy. Evidence on shortened obinutuzumab infusion in CLL remains limited. AIMS: To evaluate the safety, feasibility, and clinical outcomes of a 2-h obinutuzumab infusion protocol in treatment-naïve CLL. METHODS: This retrospective single-center cohort study included 112 treatment-naïve patients receiving venetoclax-obinutuzumab (n = 72) or obinutuzumab-chlorambucil (n = 40). From cycle 1 day 8 onward, patients were managed according to either a shortened-infusion strategy (Short; n = 64) or a standard-duration strategy (Long; n = 48). The primary outcome was IRR incidence and severity; secondary outcomes included chair time, response rate, and progression-free survival. RESULTS: IRR rates did not differ significantly between the Short and Long groups (71.9% vs. 83.3%; odds ratio, 0.51; 95% confidence interval, 0.17-1.41; p = 0.18). Most IRRs occurred during the first infusion (87.4%), before implementation of the shortened protocol. Because cycle 1 day 1 and day 2 were administered using the same standard protocol in both groups, the safety comparison relevant to the shortened-infusion strategy begins at cycle 1 day 8; IRRs were infrequent from cycle 1 day 8 onward, and none occurred from cycle 1 day 15 onward, when eligible patients in the Short group were receiving the 2-h infusion. Grade 2 reactions predominated (91.6%); no Grade 4 IRRs occurred among the 112 patients included in the analysis. The shortened protocol saved 1.8 h per visit and 11.2 h per patient (42%). No apparent adverse signal in response or progression-free survival was observed. CONCLUSIONS: In frontline CLL care, a 2-h obinutuzumab infusion from cycle 1 day 8 was feasible, safe, and substantially reduced chair time, supporting its use to improve outpatient treatment efficiency.