Cost effectiveness of rituximab for non-Hodgkin's lymphoma: a systematic review

BACKGROUND

The monoclonal antibody rituximab has shown clinical effectiveness in combination with chemotherapy for the treatment of non-Hodgkin's lymphoma (NHL) in several randomized controlled studies. Rituximab maintenance therapy is associated with significant improvement in progression-free and overall survival in patients with NHL. However, treatment with rituximab causes considerable costs for healthcare systems.

OBJECTIVE

This article provides an overview of economic evaluations of rituximab and appraises their methodological quality.

METHODS

A systematic literature search of cost-effectiveness studies on rituximab was carried out in nine electronic databases: MEDLINE, EMBASE, Cochrane Database of Systematic Reviews (CDSR), the German Agency of Health Technology Assessment (DAHTA) database, German Institute for Quality Improvement (DIQ)-Literatur, DIQ-Projekte, Database of Abstracts of Reviews of Effects (DARE), Health Technology Assessments (HTA) database and Sozialmedizin (SOMED) [languages: English, German, Dutch, French, Spanish and Italian; publication period: 1998 to 2010]. Based on pre-specified inclusion criteria, cost-effectiveness studies were identified that compared standard chemotherapy with standard chemotherapy plus rituximab in patients with a subtype of NHL. The methodological quality of the studies was assessed using a quality checklist.

RESULTS

Fourteen economic evaluations from seven different countries were included in the review. All economic evaluations reported incremental cost-effectiveness ratios (ICERs) for the add-on therapy with rituximab that were below the country-specific thresholds. The studies differed significantly in their characteristics and methodological rigour. Most studies lacked transparency regarding identification and justification of data. In several studies, the rationale for the model structure was not described appropriately.

CONCLUSION

Adding rituximab to standard chemotherapy is considered a cost-effective treatment option for NHL. However, the results of the analyses should be interpreted with caution due to methodological limitations.

Mantle cell lymphoma: biological insights and treatment advances

Mantle cell lymphoma (MCL) exhibits considerable molecular heterogeneity and complexity, and is regarded as one of the most challenging lymphomas to treat. With increased understanding of the pathobiology of MCL, it is proposed that MCL is the result of 3 major converging factors, namely, deregulated cell cycle pathways, defects in DNA damage responses, and dysregulation of cell survival pathways. In the present era of targeted therapies, these biologic insights have resulted in the identification of several novel rational targets for therapeutic intervention in MCL that are undergoing active clinical testing. To date, there is no standard of care in MCL. Several approaches including conventional anthracycline-based therapies and intensive high-dose strategies with and without stem cell transplantation have failed to produce durable remissions for most patients. Moreover, considering the heterogeneity of MCL, it is increasingly being recognized that risk-adapted therapy might be a relevant therapeutic approach in this disease. At the first and second Global Workshops on Mantle Cell Lymphoma, questions addressing advances in the pathobiology of MCL, optimization of existing therapies, assessment of current data with novel therapeutic strategies, and the identification of molecular or phenotypic risk factors for utilization in risk-adapted therapies were discussed and will be summarized herein.

Ten years of rituximab in NHL

BACKGROUND

Rituximab, a chimeric mouse/human monoclonal antibody targeting the pan-B-cell antigenic marker CD20, was the first monoclonal antibody licensed for use in the treatment of cancer.

OBJECTIVE

This review focuses on the impact of rituximab in the treatment of patients with B-cell non-Hodgkin lymphoma (NHL).

METHODS

Three key areas related to the use of rituximab in B-cell NHL are discussed: mechanism of action, clinical efficacy in both indolent and aggressive disease, and safety of its use as both monotherapy and in combination with chemotherapy.

RESULTS/CONCLUSIONS

Rituximab has demonstrated significant clinical efficacy in the treatment of NHL, particularly in combination with chemotherapy, and its use has revolutionized the treatment of both indolent and aggressive B-cell NHL over the past decade. Furthermore, consistent toxicity data have been obtained with a safe and tolerable profile in most patients.

[Rituximab cost analysis for maintenance treatment of patients with follicular lymphoma]

INTRODUCTION

In patients with refractory or recurrent follicular lymphoma responding to induction therapy with CHOP or rituximab + CHOP, maintenance treatment with rituximab compared to the "observation" option improves both overall survival and progression-free survival.

OBJECTIVE

Estimate whether maintenance treatment with rituximab is a cost-effective intervention compared to the clinical practice of "observing" its evolution.

METHOD

POPULATION

the EORTC 20981 clinical trial population.

PERSPECTIVE

Spanish National Health System (direct healthcare costs).

DESIGN

Incremental cost-effectiveness analysis, with a transition model between states of health.

MAIN VARIABLES

cost of gaining a quality-adjusted life year (QALY), per life year gained (LYG) and per progression-free LYG. Premises of the basic case: Weibull distribution for survival extrapolation, 5 year duration of the benefits of the treatment, time horizon of 10 years and annual discount rate (costs and benefits) of 3.5%. These premises were modified in the sensitivity analyses.

RESULTS

Deterministic analysis: the cost per QALY gained was 9,358 euro, 8,493 euro per LYG and 5,485 euro per progression-free LYG. Probabilistic and sensitivity analysis: they confirmed the stability of the deterministic analysis results.

CONCLUSIONS

According to this model, maintenance treatment with rituximab is cost-effective (cost per LYG < 30,000 euro) in patients with resistant or recurrent follicular lymphoma responding to induction treatment, in comparison to the usual practice of observing patients' evolution.

Prevalence of bortezomib-resistant constitutive NF-kappaB activity in mantle cell lymphoma

Background

The proteasome inhibitor bortezomib can inhibit activation of the transcription factor NF-κB, a mechanism implicated in its anti-neoplastic effects observed in mantle cell lymphoma (MCL). However, NF-κB can be activated through many distinct mechanisms, including proteasome independent pathways. While MCL cells have been shown to harbor constitutive NF-κB activity, what fraction of this activity in primary MCL samples is sensitive or resistant to inhibition by bortezomib remains unclear.

Results

Proteasome activity in the EBV-negative MCL cell lines Jeko-1 and Rec-1 is inhibited by greater than 80% after exposure to 20 nM bortezomib for 4 hours. This treatment decreased NF-κB activity in Jeko-1 cells, but failed to do so in Rec-1 cells when assessed by electrophoretic mobility shift assay (EMSA). Concurrently, Rec-1 cells were more resistant to the cytotoxic effects of bortezomib than Jeko-1 cells. Consistent with a proteasome inhibitor resistant pathway of activation described in mouse B-lymphoma cells (WEHI231) and a breast carcinoma cell line (MDA-MB-468), the bortezomib-resistant NF-κB activity in Rec-1 cells is inhibited by calcium chelators, calmodulin inhibitors, and perillyl alcohol, a monoterpene capable of blocking L-type calcium channels. Importantly, the combination of perillyl alcohol and bortezomib is synergistic in eliciting Rec-1 cell cytotoxicity. The relevance of these results is illuminated by the additional finding that a considerable fraction of primary MCL samples (8 out of 10) displayed bortezomib-resistant constitutive NF-κB activity.

Conclusion

Our findings show that bortezomib-resistant NF-κB activity is frequently observed in MCL samples and suggest that this activity may be relevant to MCL biology as well as serve as a potential therapeutic target.

Immunotherapy in mantle cell lymphoma: anti-CD20-based therapy and beyond

Mantle cell lymphoma (MCL), an aggressive non-Hodgkin's lymphoma characterized by t(11; 14)(q13; q32) chromosomal translocation and overexpression of cyclin D1, has the worst prognosis among all lymphomas. Recent advances in biology, genetics, and immunology have supported the development of immunotherapy in MCL. Rituximab monotherapy in MCL has limited activity. It is more effective when used in combination with chemotherapy such as R-CHOP, R-hyperCVAD/MTX-Ara-C, or R-FCM as front-line or salvage therapy for mantle cell lymphoma. Maintenance with Rituximab was shown to prolong response duration. Although most results have suggested that combining autologous stem cell transplantation with Rituximab may lead to durable remission, the sample size was not sufficient to declare survival benefit. Anti-CD20 radioimmunoconjugates (RICs) (90)Yttrium-ibritumomab tiuxetan and (131)Iodine-tositumomab have been used in mantle cell lymphoma even when patients are relatively resistant to Rituximab-based therapy. Allogeneic stem cell transplantation is a treatment modality in advanced or relapsed MCL, particularly using reduced-intensity conditioning. MCL may have high response rates and sustained remissions after donor lymphocyte infusion. Dendritic cells (DCs) fused with MCL cells for immunostimulation have preliminarily shown anti-lymphoma effects as well. Idiotype vaccination in MCL patients following Rituximab-containing chemotherapy induced tumor-specific T-cell immunity in the absence of B cells. Other immunotherapy, such as the combination of thalidomide with Rituximab, has shown substantial antitumor activity. A Phase I/II study is ongoing to determine the maximum tolerated dose (MTD) and the efficacy of lenalidomide in combination with Rituximab for relapsed/refractory MCL. This review summarizes the latest and exciting advances in MCL.

Chemotherapy plus Rituximab versus chemotherapy alone for B-cell non-Hodgkin's lymphoma

BACKGROUND

Rituximab has been shown to improve response rates and progression free survival when added to chemotherapy in patients with indolent and mantle cell lymphoma. However, the impact of R on overall survival (OS) when given in combination with chemotherapy (R-chemo) has remained unclear so far.

OBJECTIVES

We thus performed a comprehensive systematic review in this group of patients to compare R-chemo with chemotherapy alone with respect to OS. Other endpoints were overall response rate (ORR), toxicity and disease control as assessed by measures such as time to treatment failure (TTF), event free-survival (EFS), progression free-survival (PFS) and time to progression (TTP).

SEARCH STRATEGY

We searched the Cochrane Central Register of Controlled Trials (CENTRAL) (The Cochrane Library), MEDLINE, EMBASE and conference proceeding from 1990 to 2005.

SELECTION CRITERIA

Only randomised controlled trials (RCT) comparing R-chemo with chemotherapy alone in patients with newly diagnosed or relapsed indolent lymphoma and mantle cell lymphoma (MCL) were included.

DATA COLLECTION AND ANALYSIS

Two review authors extracted data and assessed the study quality. Number needed to treat (NNT) were calculated to facilitate interpretation.

MAIN RESULTS

Seven randomised controlled trials involving 1943 patients with follicular lymphoma, mantle cell lymphoma, or other indolent lymphomas were included in the meta-analysis. Five studies were published as full-text articles, and two were in abstract form. Patients treated with R-chemo had better overall survival (hazard ratio [HR] for mortality 0.65; 95% confidence interval (CI) 0.54 to 0.78), overall response (relative risk of tumour response 1.21; 95% CI 1.16 to 1.27), and disease control (HR of disease event 0.62; 95% CI 0.55 to 0.71) than patients treated with chemotherapy alone. R-chemo improved overall survival in patients with follicular lymphoma (HR for mortality 0.63; 95% CI 0.51 to 0.79) and in patients with mantle cell lymphoma (HR for mortality 0.60; 95% CI 0.37 to 0.98). However, in the latter case, there was heterogeneity among the trials (P 0.07), making the survival benefit less reliable.

AUTHORS' CONCLUSIONS

The systematic review demonstrated improved OS for patients with indolent lymphoma, particularly in the subgroups of follicular and in mantle cell lymphoma when treated with R-chemo compared to chemotherapy alone.

Immunochemotherapy With Rituximab and Overall Survival in Patients With Indolent or Mantle Cell Lymphoma: A Systematic Review and Meta-analysis

BACKGROUND

Addition of the anti-CD20 monoclonal antibody rituximab to chemotherapy (R-chemo) has been shown to improve response rates and progression-free survival in patients with indolent or mantle cell lymphoma. However, the impact of R-chemo on overall survival is unclear. We performed a comprehensive systematic review and meta-analysis to examine the efficacy of combined immunochemotherapy using R-chemo compared with the identical chemotherapy alone with respect to overall survival in patients with advanced indolent lymphoma or mantle cell lymphoma.

METHODS

Medical databases and conference proceedings were searched for randomized controlled trials published from January 1990 through December 2005 that compared R-chemo with chemotherapy alone in patients with newly diagnosed or relapsed indolent lymphoma or mantle cell lymphoma. We included full-text and abstract publications. Endpoints were overall survival, disease control, overall response, and toxicity. A fixed-effects model was assumed in all meta-analyses. For binary data, the relative risk was used as an indicator of treatment effect, and the Mantel-Haenszel method was used to pool relative risks. Statistical tests for heterogeneity were one-sided; statistical tests for effect estimates were two-sided.

RESULTS

Seven randomized controlled trials involving 1943 patients with follicular lymphoma, mantle cell lymphoma, or other indolent lymphomas were included in the meta-analysis. Five studies were published as full-text articles, and two were in abstract form. Patients treated with R-chemo had better overall survival (hazard ratio [HR] for mortality = 0.65; 95% confidence interval [CI] = 0.54 to 0.78), overall response (relative risk of tumor response = 1.21; 95% CI = 1.16 to 1.27), and disease control (HR of disease event = 0.62; 95% CI = 0.55 to 0.71) than patients treated with chemotherapy alone. R-chemo improved overall survival in patients with follicular lymphoma (HR for mortality = 0.63; 95% CI = 0.51 to 0.79) and in patients with mantle cell lymphoma (HR for mortality = 0.60; 95% CI = 0.37 to 0.98). However, in the latter case, there was heterogeneity among the trials (P = .07), making the survival benefit less reliable.

CONCLUSION

In patients with indolent or mantle cell lymphoma, R-chemo is superior to chemotherapy alone with respect to overall survival.

Controversies in Follicular Lymphoma: “Who, What, When, Where, and Why?” (Not Necessarily in That Order!)

Follicular lymphoma (FL) is the most common subtype of indolent lymphoma. Specific “facts” about FL that were generated by past research and have been passed down as dogma to a majority of practicing oncologists over the past 20 to 30 years that need to be revisited, include: (1) do not initiate therapy soon after diagnosis in asymptomatic, advanced-stage patients since it does not change outcome; (2) initiate therapy with single-agent oral alkylators when intervention needed and “save” more aggressive combination chemotherapy for “later” since the standard chemotherapy regimen used did not seem to impact survival; (3) FL is an incurable disease and palliation of symptoms was an acceptable approach to the expected pattern of repeated relapses; (4) transformation of FL is independent of the type or timing of therapies received by a patient; (5) median overall survival (OS) for FL patients is 8–10 years. Although the heterogeneity of FL will never change, we are developing the scientific tools to identify and better understand the biologic and genetic features associated with its clinical variability. In the current exciting era of targeted therapies (e.g., rituximab, radioimmunoconjugates) and novel treatment approaches demonstrating an improvement in treatment outcomes (e.g., disease-free survival and OS), our old beliefs and historically accepted dogma need to be retested and revitalized. The optimal combination(s) of old and new agents and the optimal timing of when to initiate and how to sequence specific therapies will require data from well-designed clinical trials that should include important correlative laboratory studies.