Which of These Treatment Combinations Extend Survival for DLBCL?

A real-world study presented at the 2020 ASH Annual Meeting observed no significant survival differences in patients with relapsed/refractory diffuse large B-cell lymphoma (DLBCL) who were treated with bendamustine plus rituximab (BR) versus rituximab plus gemcitabine and oxaliplatin (R-GemOx).

Researchers retrospectively analyzed real-world data from the Surveillance, Epidemiology, and End Results registry as well as linked Medicare enrollment data and insurance claims. They identified patients with a cancer diagnosis between 2004 and 2016 and included 3,606 patients aged >65 years who were diagnosed with DLBCL not otherwise specified and received second-line BR (n=308) or R-GemOx (n=131) alone. Patients with evidence of prior hospice care were excluded.

Median follow-up was 12.42 months (range, 4.78-28.41 months) in the BR group and 7.72 months (range, 3.02-21.14 months) in the R-GemOx group. Patients treated with R-GemOx were more likely to be younger (median age, 77 years vs. 80 years) and male (61.1% vs. 45.8%). A similar proportion of patients were primary refractory in each treatment group (BR, 20.8%; R-GemOx, 21.4%; P=0.99).

The unadjusted median duration of second-line treatment was 11.4 weeks (range, 4.29-20.04 weeks) with BR and 8.14 weeks (range, 4.07-14.71 weeks) with R-GemOx. Median overall survival (OS) was 16.39 months in the BR group (95% confidence interval [CI], 13.01-19.48) and 8.74 months in the R-GemOx group (95% CI, 7.00-12.98). After adjusting for covariates, median OS was 16.39 months (95% CI, 12.88-19.48) and 9.26 months (95% CI, 7.10-14.36), respectively. The hazard ratio (HR) for adjusted OS in the second line of therapy was 1.24 (95% CI, 0.97-1.58) for R-GemOx compared with BR. After propensity score adjustment, the HR for OS in the third line of therapy was 0.996 (95% CI, 0.70-1.42) for R-GemOx compared with BR.

The study is limited by the assumption that all important variables have been accounted for in the propensity scoring and by the use of database information, which may not be generalizable to a wider patient population.

“In the absence of comparative data from randomized, controlled trials, this real-world data analysis demonstrates similar real-world effectiveness of the two regimens in relapsed/refractory DLBCL,” the researchers concluded.

Reference

Castro F, Surinach A, Launonen A, et al. Comparative Effectiveness of Bendamustine Plus Rituximab (BR) and Rituximab Plus Gemcitabine and Oxaliplatin (R-GemOx) in Relapsed/Refractory Diffuse Large B-Cell Lymphoma. Abstract 3042. Presented at the 62nd American Society of Hematology Annual Meeting & Exposition, December 2-11, 2020.