Cost‐Effectiveness Analysis of Obinutuzumab for Previously Untreated Chronic Lymphocytic Leukaemia in Portuguese Patients who are Unsuitable for Full-Dose Fludarabine-Based Therapy

Background Chronic lymphocytic leukaemia (CLL) mostly affects patients with comorbidities and limited therapeutic options. Obinutuzumab in combination with chlorambucil (GClb) is a new therapeutic option for previously untreated CLL patients who are unsuitable for full-dose fludarabine-based therapy. This combination delays disease progression but incurs additional costs; thus, an assessment of its value for money is relevant. Objective To estimate the incremental cost-utility ratio of GClb in comparison with (i) rituximab in combination with chlorambucil (RClb), and (ii) chlorambucil alone (Clb) from the perspective of the Portuguese National Health Service (NHS). Methods A Markov model was used to predict disease progression. Pre‐progression clinical data were based on the latest CLL11 trial data, and post‐progression clinical data were obtained from CLL5 trial data. Utility values are from Kosmas et al. (Leuk Lymphoma 56:1320–1326, 14 ). Only direct medical costs were included. The resource consumption was estimated by a panel of Portuguese experts, and the unit costs were obtained from official sources. A discount rate of 5% was applied to costs and consequences. Results GClb and RClb were associated with an increase of 1.06 and 0.39 quality-adjusted life-years (QALY) at an additional cost of €21,720 and €9836 when compared to Clb, respectively. The cost-utility ratio of GClb versus Clb was €20,397/QALY, while RClb was extendedly dominated. Conclusions The use of GClb for previously untreated CLL patients who are unsuitable for full-dose fludarabine-based therapy incurs an incremental cost per QALY that is generally accepted in Portugal. Therefore, although there is some uncertainty, obinutuzumab is probably a cost-effective therapy in the Portuguese setting.