Rituximab serum concentrations during immuno-chemotherapy of follicular lymphoma correlate with patient gender, bone marrow infiltration and clinical response.

BACKGROUND: Treatment of follicular lymphoma with rituximab is currently recommended at a dose of 375 mg/m(2). We aimed to provide a rationale for optimal dosing and scheduling of this anti-CD20 antibody based on pharmacokinetics. DESIGN AND METHODS: Clinical efficacy of immunochemotherapy with rituximab, fludarabine and mitoxantrone followed by 2-monthly rituximab maintenance was evaluated in 29 patients with previously untreated follicular lymphoma in a prospective phase II trial (AGMT-NHL9). Pharmacokinetic analysis was assessed in 17 patients. RESULTS: Induction treatment resulted in high clinical response rates (complete remission 66%; ORR 100%). Significantly higher complete remission rates were observed in female patients (86 vs. 47%; Odds Ratio 6.8, 95% CI: 1.12; 41.82; P=0.05). Rituximab pharmacokinetic analysis showed a high variability ranging over almost 1 order of magnitude at maintenance cycle 1 (area under the curve 1,540-12,025 g/L*days). Median area under the curve was lower in men (81%) and in patients with initial bone marrow infiltration (76%). Higher rituximab serum concentrations before next therapy (C(trough)) were associated with female sex (P=0.04) as well as with absence of initial bone marrow infiltration (P=0.001). C(trough) correlated with remission quality (complete vs. partial remission; P=0.005) and progression-free survival (P=0.03). A decline in rituximab C(trough) below 25,000 ng/mL was observed 9.5 to 62 months before clinical relapse (P=0.008). CONCLUSIONS: The results of this pilot trial suggest that more differentiated dosing schedules based on gender and bone marrow infiltration should be explored for rituximab therapy for lymphoma. This study was registered in ClinicalTrials.gov (Identifier: NCT01560117).

Prolonged progression-free survival in patients with chronic lymphocytic leukemia receiving granulocyte colony-stimulating factor during treatment with fludarabine, cyclophosphamide, and rituximab.

The clinical benefit of the addition of granulocyte colony-stimulating factor (G-CSF) to standard immunochemotherapy of chronic lymphocytic leukemia (CLL) with fludarabine, cyclophosphamide, and rituximab (FCR) is still unclear. In this retrospective study we analyzed the outcome of 32 consecutive patients with CLL during treatment with FCR. Sixteen patients received G-CSF for treatment of CTC grade 3 or 4 neutropenia or febrile neutropenia at some point during therapy and 16 did not. Both groups were well balanced for clinical and biological risk factors. Overall response rates were not significantly different (94% vs. 75%; p=0.144). Interestingly, a significantly better progression-free survival (100% vs. 35.4% at 24 months; p<0.001) and even overall survival (100% vs. 77.8% at 24 months; p=0.022) was observed in patients receiving G-CSF. While the underlying cause remains to be elucidated, these data strongly suggest an association of the addition of G-CSF to FCR therapy with final patient outcome.

Nonpegylated liposomal doxorubicin is highly active in patients with B and T/NK cell lymphomas with cardiac comorbidity or higher age.

We used nonpegylated liposomal doxorubicin (NPLD) in cytostatic drug combinations to treat 37 patients with non-Hodgkin's lymphoma and pre-existing cardiac disorder or elderly patients with reduced physical state who were ineligible for conventional anthracycline-containing therapy. High remission rates were observed in this poor-risk population: Complete remission rates were 75% for diffuse large B cell lymphoma (DLBCL) and 55% for T/NK cell neoplasm (overall response rate of 80% and 89%, respectively). Twenty-seven patients (73%) are still alive after a median observation time of 14 months. No major cardiac or gastrointestinal toxicity was observed. Extravasation of NPLD in two patients resulted in mild inflammation without tissue damage. Hematologic toxicity was comparable to that of conventional anthracycline-containing regimens. We conclude that NPLD is highly active in combination chemotherapy for lymphoma with low cardiac toxicity in patients with pre-existing cardiac disorders or higher age. Moreover, we also observed remarkable efficacy in T/NK cell lymphomas.