Comparing the cost-effectiveness of rituximab maintenance and radioimmunotherapy consolidation versus observation following first-line therapy in patients with follicular lymphoma

BACKGROUND

Phase 3 randomized trials have shown that maintenance rituximab (MR) therapy or radioimmunotherapy (RIT) consolidation following frontline therapy can improve progression-free survival for patients with follicular lymphoma (FL), but the cost-effectiveness of these approaches with respect to observation has not been examined using a common modeling framework.

OBJECTIVES

To evaluate and compare the economic impact of MR and RIT consolidation versus observation, respectively, following the first-line induction therapy for patients with advanced-stage FL.

METHODS

We developed Markov models to estimate patients' lifetime costs, quality-adjusted life-years (QALYs), and life-years (LYs) after MR, RIT, and observation following frontline FL treatment from the US payer's perspective. Progression risks, adverse event probabilities, costs, and utilities were estimated from clinical data of Primary RItuximab and MAintenance (PRIMA) trial, Eastern Cooperative Oncology Group (ECOG) trial (for MR), and First-line Indolent Trial (for RIT) and the published literature. We evaluated the incremental cost-effectiveness ratio for direct comparisons between MR/RIT and observation. Model robustness was addressed by one-way and probabilistic sensitivity analyses.

RESULTS

Compared with observation, MR provided an additional 1.089 QALYs (1.099 LYs) and 1.399 QALYs (1.391 LYs) on the basis of the PRIMA trial and the ECOG trial, respectively, and RIT provided an additional 1.026 QALYs (1.034 LYs). The incremental cost per QALY gained was $40,335 (PRIMA) or $37,412 (ECOG) for MR and $40,851 for RIT. MR and RIT had comparable incremental QALYs before first progression, whereas RIT had higher incremental costs of adverse events due to higher incidences of cytopenias.

CONCLUSIONS

MR and RIT following frontline FL therapy demonstrated favorable and similar cost-effectiveness profiles. The model results should be interpreted within the specific clinical settings of each trial. Selection of MR, RIT, or observation should be based on patient characteristics and expected trade-offs for these alternatives.

Radionuclide therapy for hepatocellular carcinoma: indication, cost and efficacy

A large number of patients with hepatocellular carcinoma (HCC) will have large and/or multiple inoperable tumours, precluding percutaneous ablation, such as percutaneous ethanol, acetic acid or hot saline injection, and radiofrequency ablation. Similarly, if the tumour is not accessible percutaneously or the tumour is subcapsular or subdiaphragmatic, percutaneous therapy is ruled out. Many patients will also have associated portal vein thrombosis, making them unsuitable for chemoembolisation, depending upon the level and severity of thrombosis. Such patients can be offered internal radioisotope therapy to prolong their survival and improve the quality of life. The aim of radioisotope therapy is to deliver the radioisotope to the hepatic tumour, where it must reside for a period sufficient to deliver the scheduled dose of radiation. At the same time the amount delivered to the normal liver parenchyma and other organs should be as low as possible. A variety of radioisotopes, such as lodine-131, Yttrium-90, Rhenium-188, Holmium-166 etc. can be used for this purpose and targeting of the therapeutic agent to the tumour may be achieved by 1) direct intra-tumour implantation of the radioisotope, 2) parenteral injection of radiolabelled antibodies specific to HCC antigens (radioimmunotherapy) or, 3) injecting the radioisotope through the hepatic artery directly into the tumour or trans-arterial radioisotope therapy (TART). The radioisotope therapy appears to be a very reasonable and effective therapeutic alternative, a) for the treatment of large inoperable HCC, particularly with portal vein thrombosis, b) treatment of small inoperable tumours unsuitable for percutaneous therapy because of any reason, c) as a neoadjuvant therapy before hepatic transplantation to reduce the risk of recurrence in the graft or before hepatic resection to shrink the tumour size, and d) as an adjuvant therapy, after surgery or percutaneous ablative therapy to reduce the risk of recurrence. Further, it can be very affordable if generator produced Re-188 is used, which appears to be equally or more effective and useful than other currently available radioisotopes. The availability of Re-188 in a generator form makes its storage, transportation, elution and usage very convenient and cost-effective, particularly at remote places and in developing countries. The use of generator also makes Re-188 available on a constant and need to need basis.

National cancer institute perspectives

The National Cancer Institute (NCI) Perspectives this year presented information on the systemic targeted radionuclide therapy (STaRT) research projects: (1) being investigated at the NCI's Intramural Center for Cancer Research; (2) funded by NCI's Radiation Research Program and other extramural programs; and (3) the appropriate National Institutes of Health/NCI funding mechanisms applicable to researchers for obtaining funds for STaRT projects.