Biosimilar Rituximab Plus CHOP Effective, Well-Tolerated Among Patients With Previously Untreated CD20-Positive DLBCL

Sandoz biosimilar rituximab (SDZ-RTX) combined with a cyclophosphamide, doxorubicin, vincristine, and prednisone (CHOP) regimen was effective and well-tolerated as a frontline treatment for patients with CD-20 positive diffuse large B-cell lymphoma, according to results from REFLECT, a 2-year real-world study.

The SDZ-RTX clinical development program “demonstrated that SDZ-RTX matched reference rituximab on all clinically relevant attributes, in terms of pharmacokinetics, pharmacodynamics, efficacy, safety, and immunogenicity,” wrote Manfred Welslau, MD, Onkologie Aschaffenburg, Klinikum Aschaffenburg-Alzenau, Aschaffenburg, Germany, and colleagues. “However, no patients with DLBCL were involved in these confirmatory studies.”

To investigate this rituximab biosimilar among patients with DLBCL, researchers conducted a real-world, multicenter, open-label, single-arm, non-interventional, post-approval study of SDZ-RTX in combination with CHOP among adult patients with treatment-naïve CD20‑positive DLBCL. The patients were administered SDZ-RTX-CHOP every 2 or 3 weeks, over 6 to 8 cycles. The efficacy was evaluated according to the complete response (CR) rate at the end of R-CHOP treatment, as assessed by the treating physician. Additionally, progression-free survival (PFS) was assessed at 24 months.

A total of 169 patients were analyzed in this study. At baseline, 19.5% and 24.3% of patients had Ann Arbor disease, at stage III or IV respectively, and 80.5% of patients had an Eastern Cooperative Oncology Group Performance Status of 0 or 1. A total of 100 (59.2%) patients completed the 24-month observation period.

Results indicated that 110 [65.1%; 95% confidence interval [CI], 57.4 to 72.3] patients achieved CR as best response and 50 (29.6%; 95% CI, 22.8 to 37.1) patients achieved partial response. Overall best response rate was 94.7% (95% CI, 90.1 to 97.5). The 1-year PFS was 84.9% (95% CI, 78.2 to 89.6) and 2-year PFS was 78.5% (95% CI, 70.9 to 84.4). The median PFS was not reached within the observational period. There were 31.4% of patients who experienced an adverse event suspected to be related to the study drug.

“This real-world, 2-year study reconfirms that first-line treatment of CD20-positive DLBCL with R-CHOP using SDZ-RTX is effective and well-tolerated,” concluded Welslau and study coauthors.

Source:

Welslau M, Kubuschok B, Topaly J, et all. REFLECT: prospective multicenter non-interventional study evaluating the effectiveness and safety of Sandoz rituximab (SDZ-RTX; Rixathon^®) in combination with CHOP for the treatment of patients with previously untreated CD20-positive diffuse large B-cell lymphoma. Ther Adv Hem. Published online July 22, 2023. doi:10.1177/20406207231183765