The role of sex and weight on rituximab clearance and serum elimination half-life in elderly patients with DLBCL.

Pharmacokinetics of 8 doses of rituximab (375 mg/m(2)) given in combination with 2-week cyclophosphamide, hydroxydaunorubicin, vincristine, and prednisone/prednisolone (CHOP-14) was determined by ELISA in 20 elderly patients with diffuse large B-cell lymphoma (DLBCL) 10 minutes before and after each infusion and 1 week and 1, 2, 3, 6, and 9 months after the last infusion. Population pharmacokinetic modeling was performed with nonlinear mixed-effect modeling software (NONMEM VI). Concentration-time data were fitted into an open 2-compartment model and total clearance, central compartment volume, intercompartment clearance, and volume of distribution at steady-state (Vd(ss)) were investigated. Total clearance was 9.43 mL/h and Vd(ss) was 9.61 l. Rituximab clearance was reduced (8.21 mL/h vs 12.68 mL/h; P = .003) and elimination half-life was prolonged in women compared with men (t(1/2ß) = 30.7 vs 24.7 days; P = .003). Body weight also affected Vd(ss) (0.1 l increase of Vd(ss) per kilogram above median of 75 kg). A sex-dependent effect and the higher weight of males contribute to their faster rituximab clearance, which might explain why elderly males benefit less from the addition of rituximab to CHOP than females. This trial was registered on www.clinicaltrials.gov as numbers NCT00052936, EU-20243 (RICOVER-60 Trial), EU-20534, and NCT00726700 (Pegfilgrastim Trial).

Six versus eight cycles of bi-weekly CHOP-14 with or without rituximab in elderly patients with aggressive CD20+ B-cell lymphomas: a randomised controlled trial (RICOVER-60).

BACKGROUND: Cyclophosphamide, doxorubicin, vincristine, and prednisolone (CHOP) is used to treat patients with non-Hodgkin lymphoma. Interval decrease from 3 weeks of treatment (CHOP-21) to 2 weeks (CHOP-14), and addition of rituximab to CHOP-21 (R-CHOP-21) has been shown to improve outcome in elderly patients with diffuse large B-cell lymphoma (DLBCL). This randomised trial assessed whether six or eight cycles of R-CHOP-14 can improve outcome of these patients compared with six or eight cycles of CHOP-14. METHODS: 1222 elderly patients (aged 61-80 years) were randomly assigned to six or eight cycles of CHOP-14 with or without rituximab. Radiotherapy was planned to sites of initial bulky disease with or without extranodal involvement. The primary endpoint was event-free survival; secondary endpoints were response, progression during treatment, progression-free survival, overall survival, and frequency of toxic effects. Analyses were done by intention to treat. The trial is registered on National Cancer Institute website, number NCT00052936 and as EU-20243. FINDINGS: 3-year event-free survival was 47.2% after six cycles of CHOP-14 (95% CI 41.2-53.3), 53.0% (47.0-59.1) after eight cycles of CHOP-14, 66.5% (60.9-72.0) after six cycles of R-CHOP-14, and 63.1% (57.4-68.8) after eight cycles of R-CHOP-14. Compared with six cycles of CHOP-14, the improvement in 3-year event-free survival was 5.8% (-2.8-14.4) for eight cycles of CHOP-14, 19.3% (11.1-27.5) for six cycles of R-CHOP-14, and 15.9% (7.6-24.2) for eight cycles of R-CHOP-14. 3-year overall survival was 67.7% (62.0-73.5) for six cycles of CHOP-14, 66.0% (60.1-71.9) for eight cycles of CHOP-14, 78.1% (73.2-83.0) for six cycles of R-CHOP-14, and 72.5% (67.1-77.9) for eight cycles of R-CHOP-14. Compared with treatment with six cycles of CHOP-14, overall survival improved by -1.7% (-10.0-6.6) after eight cycles of CHOP-14, 10.4% (2.8-18.0) after six cycles of R-CHOP-14, and 4.8% (-3.1-12.7) after eight cycles of R-CHOP-14. In a multivariate analysis that used six cycles of CHOP-14 without rituximab as the reference, and adjusting for known prognostic factors, all three intensified regimens improved 3-year event-free survival (eight cycles of CHOP-14: RR [relative risk] 0.76 [0.60-0.95], p=0.0172; six cycles of R-CHOP-14: RR 0.51 [0.40-0.65], p<0.0001; eight cycles of R-CHOP-14: RR 0.54 [0.43-0.69], p<0.0001). Progression-free survival improved after six cycles of R-CHOP-14 (RR 0.50 [0.38-0.67], p<0.0001), and eight cycles of R-CHOP-14 (RR 0.59 [0.45-0.77], p=0.0001). Overall survival improved only after six cycles of R-CHOP-14 (RR 0.63 [0.46-0.85], p=0.0031). In patients with a partial response after four cycles of chemotherapy, eight cycles were not better than six cycles. INTERPRETATION: Six cycles of R-CHOP-14 significantly improved event-free, progression-free, and overall survival over six cycles of CHOP-14 treatment. Response-adapted addition of chemotherapy beyond six cycles, though widely practiced, is not justified. Of the four regimens assessed in this study, six cycles of R-CHOP-14 is the preferred treatment for elderly patients, with which other approaches should be compared.

Combined cyclophosphamide, vincristine, doxorubicin, and prednisone (CHOP) improves response rates but not survival and has lower hematologic toxicity compared with combined mitoxantrone, chlorambucil, and prednisone (MCP) in follicular and mantle cell lymphomas: results of a prospective randomized trial of the German Low-Grade Lymphoma Study Group.

BACKGROUND: In patients with advanced-stage follicular lymphoma (FL) and mantle cell lymphoma (MCL), conventional chemotherapy remains a noncurative approach, and no major improvement in overall survival has been achieved in recent decades. METHODS: The German Low-Grade Lymphoma Study Group performed a randomized trial comparing combined cyclophosphamide, vincristine, doxorubicin, and prednisone (CHOP) chemotherapy with combined mitoxantrone, chlorambucil, and prednisone (MCP) chemotherapy as first-line therapy for patients with advanced-stage FL or MCL. RESULTS: Three hundred sixty-three patients with advanced-stage FL (n = 277 patients) or MCL (n = 86 patients) entered the trial and were evaluable fully. CHOP resulted in a significantly higher overall response rate in patients with FL (91% vs. 82%; P = .026) and a similar tendency in patients with MCL (87% vs. 73%; P = .080). However, no significant differences were observed in the time to treatment failure or in overall survival. CHOP produced significantly more nonhematologic toxicities, whereas MCP was associated with more severe hematologic side effects. The proportion of patients who successfully underwent peripheral blood stem cell collection was significantly lower after MCP (44% vs. 93% after CHOP; P = .0003). CONCLUSIONS: Taking into account that, currently, chemotherapy regularly is combined with rituximab as first-line therapy for FL and MCL, the data from this study may have an impact on the type of chemotherapy to be applied in such combinations. Particularly in younger, high-risk patients who are candidates for autologous stem cell transplantation, CHOP should be preferred over MCP.

Treatment strategies in follicular lymphomas: current status and future perspectives.

Although little progress has been made in the treatment of follicular lymphomas (FL) within the last few decades, several new therapeutic modalities have recently demonstrated promising activity. These include myeloablative therapy followed by autologous stem cell transplantation in younger patients in first remission revealing a significant prolongation of remission duration in three prospective randomized trials, whereas the impact on overall survival still needs to be determined. Adding the anti-CD20 antibody rituximab to conventional chemotherapy resulted in a significant increase in remission rate, remission duration and in two of four currently available prospective randomized studies even in a longer overall survival. A prolongation of remission duration was also seen when rituximab was administered as maintenance after cytoreductive therapy or by prolonged application as a single agent. Radioimmunotherapy (RIT) with radioisotopes coupled to monoclonal antibodies revealed encouraging data in several phase II studies. Prospective randomized studies are warranted, however, to define the impact of RIT on FL therapy. New therapeutic perspectives also emerge from increasing insights into the biology of the disease that unravel molecular targets for novel agents, some of which have entered clinical evaluation already.

Use of polymorphisms in the noncoding region of the human mitochondrial genome to identify potential contamination of human leukemia-lymphoma cell lines.

The availability of the complete sequence of human mitochondrial DNA (mtDNA) has proven extremely useful in phylogenetic studies, forensic science and the determination of chimerism after allogeneic stem cell transplantation. In this study, we could demonstrate that the analysis of mtDNA polymorphisms is a quick and reliable method to identify contamination of human hematopoietic cell lines. This assay is based on PCR-sequencing of three hypervariable segments of the control region of mtDNA (hypervariable region (HRV) 1, 2 and 3). All three regions contain a large number of single-base polymorphisms. mtDNA was isolated according to standard laboratory procedures and amplified by PCR. Subsequently products were sequenced and evaluated with a semiautomated DNA sequencer system. So far, 21 human leukemia-lymphoma (LL) cell lines and nine other human cell lines were screened for contamination by other cell lines applying this method. We conclude that analysis of mtDNA polymorphisms is a quick, reliable and inexpensive method to detect intra - and interspecies cross-contamination and for the authentication of human LL cell lines. In comparison to other methods (cytogenetics, fluorescence in situ hybridization or immunophenotyping), this technique is less laborious and time consuming.

Genetic analysis of de novo CD5+ diffuse large B-cell lymphomas suggests an origin from a somatically mutated CD5+ progenitor B cell.

CD5(+) diffuse large B-cell lymphomas (DLBLs) have recently been described as a particular subgroup of DLBLs. Classical banding and interphase cytogenetic analyses targeting ATM, TP53, and P16(INK4a) genes and the D13S25 locus from 13 CD5(+) DLBLs were compared with 55 CD5(-) DLBLs. Additionally, analysis of somatic mutations of the immunoglobulin heavy chain variable region (IgVH) genes were performed in CD5(+) DLBLs. CD5(+) DLBLs were somatically mutated (7 of 8 cases) and were negative for t(11;14)(q13;q32) and t(14;18)(q32;q21), whereas t(3;14)(q27;q32) was found in only one tumor. Trisomy 3 and gains on chromosomes 16/16p and 18/18q were significantly overrepresented in CD5(+) DLBLs. No ATM deletions were detected. The prevalence of deletions at the D13S25 locus was significantly higher in CD5(+) DLBLs (4 of 12 [33%]) compared with CD5(-) DLBLs (4 of 42 [10%]), as were p16(INK4a) deletions (33% versus 8%). On the basis of these findings, CD5(+) DLBLs are likely to arise from the same progenitor cell as the mutated variant of CD5(+) lymphocytic lymphoma/B-cell chronic lymphocytic leukemia (B-CLL).