Gemcitabine-oxaliplatin plus rituximab (R-GemOx) as first-line treatment in elderly patients with diffuse large B-cell lymphoma: a single-arm, open-label, phase 2 trial

Abstract

Background: The combination of rituximab, gemcitabine, and oxaliplatin (R-GemOx) has shown high efficacy with a low toxicity profile in elderly patients with relapsed and refractory diffuse large B-cell lymphoma. We aimed to evaluate the efficacy, safety, and feasibility of the R-GemOx regimen as a first-line treatment in elderly patients with diffuse large B-cell lymphoma.

Methods: In this single-arm, open-label, phase 2 clinical trial, we enrolled patients with previously untreated, histologically confirmed, CD20-positive diffuse large B-cell lymphoma, aged 70 years or older, or aged 60-69 years with an Eastern Cooperative Oncology Group (ECOG) performance status score of 2 or greater. Patients were recruited from Jiangsu Province Hospital (Jiangsu Sheng, China). The R-GemOx regimen was administered intravenously: rituximab 375 mg/m² on day 0; gemcitabine 1 g/m² on day 1; and oxaliplatin 100 mg/m² on day 1. The cycle was repeated every 14 days. Six cycles were planned if the patient achieved at least partial remission after the interim assessment. The primary endpoint was the proportion of patients who achieved an overall response at the end of treatment (defined as complete response plus partial response). Analyses were done by intention to treat. The trial is ongoing but no longer recruiting patients. This study is registered with ClinicalTrials.gov, number NCT01670370.

Findings: Between Aug 22, 2012, and Dec 31, 2015, 60 patients were enrolled and included in the study. The median age of the patients was 75 years (IQR 70-80) and 27 (45%) patients had a poor performance status with an ECOG score of 2 or greater. 45 (75%) patients achieved an overall response at the end of the treatment, with 28 (47%) achieving a complete response. Common grade 3-4 adverse events were haematological toxicities (thrombocytopenia in five [8%] patients, anaemia in four [7%], and neutropenia in nine [15%]) and gastrointestinal complications (nausea in five [8%] patients, vomiting in three [5%], and diarrhoea in one [2%]). No treatment-related deaths were reported.

Interpretations: The R-GemOx regimen shows high efficacy and safety as a front-line treatment in an elderly patient subpopulation and might be a therapeutic option for management of diffuse large B-cell lymphoma in elderly patients.

Funding: National Natural Science Foundation of China, Jiangsu Province's Medical Elite Programme, Project of National Key Clinical Specialty, National Science & Technology Pillar Program, Jiangsu Provincial Special Program of Medical, and National Science and Technology Major Project.