Rituximab Biosimilars Prove Effective in Large B-Cell Lymphoma

Abstracts from the European Hematology Association (EHA) Congress 2022 assessed the safety and effectiveness of 2 rituximab biosimilars compared with the reference product (Rituxan) in patients with untreated large B-cell lymphoma.

Sandoz Rituximab Biosimilar Over 2 Years¹

Sandoz’ rituximab biosimilar (Riximyo, Rixathon, SDZ-RTX) was approved in the European Union for the same indications as the reference product. The investigators conducted the REFLECT study, a real-world, multicenter, open-label, single-arm, non-interventional trial.

The study was also the first prospective, postapproval trial of Riximyo in combination with cyclophosphamide, doxorubicin, vincristine (Oncovin), and prednisone (R-CHOP) as a possible curative therapeutic regimen for CD-20–positive diffuse large B-cell lymphoma (DLBCL).

For inclusion, patients had to be 18 years or older with CD-20–positive DLBCL and treatment naïve. The patients received R-CHOP every 2 or 3 weeks for 6 to 8 cycles, and the investigators collected data during a 12-month treatment period and during the first 30 days after the last R-CHOP dose.

In total, 169 patients with DLBCL, of whom 52.1% were women and the mean (SD) age of the group was 67.3 (13.4) years, were included in the analysis. Overall, 110 patients achieved complete response and 50 experienced a partial response. The overall response rate was 94.7%.

Progression-free survival (PFS) at 1 year and 2 years was achieved by 84.9% and 78.5% of patients, respectively. At least 1 adverse event (AE) was reported by 143 (84.6%) patients, with the most common being anemia (24.3%), fatigue (20.7%), polyneuropathy (17.2%), and nausea (12.4%). Serious AEs were reported by 63 patients, 11 of whom were suspected to have AEs related to the treatment. In total, 8 deaths were recorded, of which 3 occurred during the treatment period.

A Danish Population Analysis of Rituximab Biosimilar²

In a population-based analysis from Denmark, investigators assessed the efficacy of R-CHOP therapy with a rituximab biosimilar vs the originator using a lymphoma registry between January 2015 and January 2022.

For inclusion, patients had to have DLBCL and be treated with CHOP or CHOP-like treatment. Data on the dates when patients were switched from Rituxan to a biosimilar were collected from pharmacies within treating hospitals, and the primary end point was PFS.

Overall, 2372 patients with a median age of 70 years were analyzed, 1049 of whom received the reference product and 1343 received the biosimilar. The 3-year PFS for the originator and biosimilar groups was 71.8% and 72.2%, respectively. The multivariable analysis revealed no significant differences in PFS or overall survival between the groups, producing hazard ratios of 0.94 (95% CI, 0.81-1.10) and 0.99 (95% CI, 0.83-1.17) in the originator and biosimilar groups, respectively.

Reference

1. Hanes V, Pan J, Mytych D, Chow V. Prospective non-interventional study on the effectiveness and safety of Sandoz rituximab (SDZ-RTX) with chop for patients with previously untreated CD20-positive diffuse large B-cell lymphoma. Presented at: EHA2022; June 9-12, 2022; Vienna, Austria. Abstract P1171.
2. Hanes V, Pan J, Mytych D, Chow V. Efficacy of rituximab and biosimilar rituximab in untreated diffuse large B-cell lymphoma, a Danish population based analysis. Presented at: EHA2022; June 9-12, 2022; Vienna, Austria. Abstract P1224.