Rituxan Approved by the FDA as Maintenance Therapy for Follicular Lymphoma

The FDA has approved Rituxan for first-line maintenance treatment of patients with advanced follicular lymphoma who responded to initial treatment with Rituxan plus chemotherapy. Rituxan is a monoclonal antibody that selectively targets the CD20 marker present on the surface of malignant (and normal) B cells.

Approval was based on the Phase III PRIMA study, which was an international, randomized trial that enrolled 1,217 patients with previously untreated FL. The trial investigated Rituxan maintenance following initial therapy of either 8 cycles of Rituxan, cyclophosphamide, vincristine, and prednisone; 6 cycles of Rituxan, cyclophosphamide, doxorubicin, vincristine, and prednisone or Rituxan, fludarabine, cyclophosphamide, and mitoxantrone. After a two-year follow up, 82% of patients that received Rituxan maintenance were in remission, compared to 66% in the observation arm.

Rituxan is an established first-line therapy in FL and recent Phase III results have demonstrated that immediate treatment with Rituxan provides a significant reduction in FL progression rates. As such, following this recent FDA approval, Rituxan will most likely be approved in three FL treatment interventions: immediate monotherapy, induction therapy in combination with chemotherapy, and maintenance monotherapy.

The NCCN already recommends Rituxan maintenance therapy, and the drug was approved for this use by the EU in October 2010. The recent FDA approval will boost the number of patients receiving Rituxan, and drug sales in the US are likely to rise, as US insurance companies will now cover the costs of the lengthy regimens.