A pilot study of epratuzumab and rituximab in combination with cyclophosphamide, doxorubicin, vincristine, and prednisone chemotherapy in patients with previously untreated, diffuse large B-cell lymphoma

Abstract

Background: In this pilot study, the authors assessed the feasibility of combination epratuzumab and rituximab plus cyclophosphamide, doxorubicin, vincristine, and prednisone (ER-CHOP) in patients with newly diagnosed diffuse large B-cell lymphoma (DLBCL).

Methods: Patients received chemotherapy on the following schedule: epratuzumab 360 mg/m2, rituximab 375 mg/m2, and standard-dose CHOP every 3 weeks for 6 to 8 cycles. The primary endpoint was the incidence of grade 4 neutropenia and grade 3 or 4 antibody infusional toxicity. Secondary endpoints were the complete response (CR) rate, the overall response rate (ORR), and progression-free survival (PFS). Weekly blood counts were obtained to monitor hematologic toxicity. Fifteen patients were enrolled and treated. Baseline patient characteristics included a median age of 63 years (range, 42-78 years), 60% of patients had stage III or IV disease, 7 patients had a low-risk International Prognostic Index (IPI) score (0 or 1), 7 patients had an intermediate-risk IPI score (2 or 3), and 1 patient was high risk.

Results: Grade 3 or 4 neutropenia was observed in 14 patients (93%) or in 28 of 92 treatment cycles (30%). Three patients developed grade > or =3 infection or fever. Eleven patients (73%) required dose reductions. No grade 3 antibody infusion-related toxicity was reported. Thirteen of 15 patients responded (ORR, 87%,), including 10 CRs (67%), 3 partial responses (20%), 1 patient with stable disease, and 1 patient with disease progression. At a median follow-up of 30 months, 13 of 15 patients remained alive. The 1-year PFS and OS rates were 93% and 100%, respectively; and the 2-year PFS and OS rates were 86% and 86%, respectively.

Conclusions: ER-CHOP every 21 days was feasible as treatment for newly diagnosed patients with DLBCL. A Phase II multicenter study is underway.