Modified FCR Regimen No More Effective for Previously Untreated Chronic Leukemia

In patients with previously untreated chronic lymphocytic leukemia (CLL), a modified fludarabine, cyclophosphamide, and rituximab (FCR) regimen with multiple-dose rituximab (FCR3) resulted in similar outcomes to those treated with FCR, a new study published online ahead of print in the journal Cancer has shown.

For the single-arm study, researchers sought to assess the safety and efficacy of FCR3, which has demonstrated improved response rates versus FCR in relapsed CLL, in patients with previously untreated CLL.

Researchers enrolled 65 patients with previously untreated CLL and treated them with FCR3. They compared the results of their sample with those of a historical cohort treated with FCR.

Results showed that 97% of patients achieved an overall response, 75% achieved a complete remission, and 62% achieved minimal residual disease negativity according to flow cytometry.

Researchers found that the median time to progression was 81 months with median overall survival not yet reached. At a median survivor follow-up of 9.7 years, 58% of patients were still alive.

In regard to safety, the most common grade 3 or 4 treatment-related adverse event was neutropenia (45%) and 11% of patients developed therapy-related myelodysplastic syndrome (t-MDS) or therapy-related acute myelogenous leukemia (t-AML) (P<0.01 vs. the historical FCR cohort).

The findings suggest that FCR3 is no more effective than FCR as frontline therapy for CLL and results in a higher incidence of t-MDS and t-AML.

Reference

1. Short NJ, Keating MJ, Wierda WG, et al. Fludarabine, cyclophosphamide, and multiple-dose rituximab as frontline therapy for chronic lymphocytic leukemia. Cancer. 2015. [epub ahead of print]. doi: 10.1002/cncr.29605.