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

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.

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

the EORTC 20981 clinical trial population.

Spanish National Health System (direct healthcare costs).

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

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.

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.

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.