Rituximab Maintenance Therapy Until Progression After Rituximab and Chemotherapy Induction in Patients With Follicular Lymphoma

SUMMARY: In this intriguing analysis, the authors reported the outcomes, when patients with low grade Follicular Lymphoma received maintenance RITUXAN® (Rituximab) beyond 2 years. The randomized, PRIMA (Primary Rituximab and Maintenance) study established that 2 years of RITUXAN® maintenance therapy after a RITUXAN® plus chemotherapy regimen, as first-line treatment for follicular lymphoma, significantly improves Progression Free Survival (PFS). The decision to give 2 years of maintenance RITUXAN® in the PRIMA study was arbitrary. It is estimated however that over 30% of the patients receiving 2 yrs of maintenance RITUXAN®, relapse at 3 years and beyond. The authors in this single institution study analyzed clinical data on 25 consecutive, unselected, treatment naïve patients with biopsy-proven diagnosis of Follicular Lymphoma. All these patients had a high tumor burden, with at least one indication for initiation of systemic therapy, which included B symptoms, cytopenia(s), bulky disease, disease progression, or impending organ damage. These patients achieved a Partial Response (PR) or a Complete Response (CR), after systemic induction treatment and subsequently received Maintenance RITUXAN® indefinitely or until disease progression. The median follow up was 5 years. The PFS in this group was 100% and 5 year overall survival was 82%. Forty five percent (45%) of the patients who achieved PR improved to CR on Maintenance RITUXAN® treatment. This benefit was accomplished with minimal toxicity with no additional complications related to hypogammaglobinemia. The authors concluded that Maintenance RITUXAN® beyond the arbitrary 2 years, is safe and may result in prolonged PFS in responding patients following chemoimmunotherapy. This provocative data begs the question whether maintenance RITUXAN® should be continued until disease progression rather than stopping at the 2 year arbitrary time frame. Yared J, Kimball A, Baer MR, et al. Clinical Lymphoma Myeloma and Leukemia 2013;13:253-257