Rituximab as maintenance therapy for patients with follicular lymphoma

Follicular lymphoma is a B-cell lymphoma characterised by an initial response to treatment that is usually followed by relapse and progression. Most patients present with advanced disease that cannot be cured. Lymphoma B-cells express CD20. Rituximab, a monoclonal anti-CD20 antibody, is expected to be active against cells that express CD20. Compared to chemotherapy alone, rituximab in combination with chemotherapy improves overall survival when used for induction therapy (treatment designed as a first step toward reducing the number of cancer cells) for patients with newly diagnosed or relapsed indolent lymphoma. Clinical trials that have shown improved event-free survival were inconsistent regarding overall (all-cause) survival. We aimed to evaluate the effects of maintenance therapy with rituximab on overall survival in patients with follicular lymphoma.

Study design: systematic review and meta-analysis of five randomised controlled trials (1056 patients).
Contribution: patients with follicular lymphoma and high tumour burden treated with rituximab maintenance therapy had better overall survival and disease control but more infections than patients who were observed without rituximab.
Implications: rituximab maintenance therapy should be added to the standard therapy of patients with relapsed or refractory (to treatment) follicular lymphoma following a successful induction treatment.
Limitations: variability in treatment regimens among trials precluded determination of the optimal rituximab maintenance regimen. One trial compared rituximab maintenance to rituximab at disease progression for patients with lower tumour burden and found both options to be comparable.
Future research should focus on:
the effect of rituximab maintenance compared to rituximab at progression;
defining which patients benefit the most from rituximab, according to burden of disease, prognostic score, the type of chemotherapy regimens used for induction, and the inclusion of rituximab in induction; and
the optimal duration of maintenance treatment, as well as its schedule.
Both randomised controlled trials and observational trials should have longer follow up in order to assess the long-term toxicity of rituximab, and should evaluate quality of life outcomes.