Five years of experience with rituximab plus high-dose dexamethasone for relapsed/refractory chronic lymphocytic leukemia.

INTRODUCTION: High-dose methylprednisolone (HDMP) in combination with rituximab is active in the treatment of relapsed/refractory chronic lymphocytic leukemia (CLL), but serious infections are frequent. Recently published data suggested that high-dose dexamethasone might be equally effective as HDMP despite a lower cumulative dose.

MATERIAL AND METHODS: We performed retrospective analysis of 60 patients with relapsed/refractory CLL (median age: 66 years; range: 37-86) treated with rituximab plus dexamethasone (R-dex) at a single tertiary center between September 2008 and October 2012. The schedule of R-dex consisted of rituximab 500 mg/m(2) i.v. day 1 (375 mg/m(2) in cycle 1) and dexamethasone 40 mg orally on days 1-4 and 10-13 repeated every 3 weeks for a maximum of 8 cycles. Unfavorable prognostic features were frequent (Rai stages III/IV in 67%, unmutated IgVH 82%, del 11q 43%, TP53 mutation/deletion 23%, bulky lymphadenopathy 58% of patients).

RESULTS: Overall response (OR)/complete remission (CR) was achieved in 75/3%. At the median follow-up of 21 months, median progression-free survival (PFS) was 8 months, median time to next treatment 12.9 months and median overall survival 25.5 months. Refractoriness to fludarabine (p = 0.04) and age ≥ 65 years (p = 0.03) were significant predictors of shorter PFS. R-dex was successfully used for debulking before allogenic stem cell transplantation in 7 patients (12%). Serious (CTCAE grade III/IV) infections occurred in 27% of patients; 20% of patients developed steroid diabetes requiring temporary short-acting insulin.

CONCLUSIONS: Our results show that R-dex is an active and well-tolerated regimen for patients with relapsed/refractory CLL; however, major infections remain frequent despite combined antimicrobial prophylaxis.