OBJECTIVES:

According to the results from the CLL-11 trial, obinutuzumab+chlorambucil (G-Clb) is superior to rituximab+chlorambucil (R-Clb) leading to an 13.8 month increase in median progression-free survival (PFS), longer time to next antileukemic treatment, higher rates of complete response and improved health-related quality of life in previously un-treated chronic lymphocytic leukemia (CLL) patients with comorbidities. The value of obinutuzumab as first line treatment for unfit CLL patients in Republic of Macedonia has not yet been reported.

METHODS:

Cost effectiveness analysis was performed using decision-analytic Markov model. Health states considered were PFS, disease progression and death. Transitional probabilities of each state in the model were based on the rates observed in CLL-11 study. Costs (2016 Euro) were collected from official, national health system data. Only direct costs (drug price, treatment administration and monitoring and post progression therapy) were included. Health states utilities were derived from the literature. Outcomes (discounted at 3% annual rate) were measured in quality adjusted life years (QALY) and costs and reported per patient as incremental cost per QALY gained ratio (ICER). Probabilistic sensitivity analysis (PSA) assessed the uncertainty around key model parameters (varied over range ±25%) and their impact on the base-case results. The model used a time horizon of 20 years.

RESULTS:

An incremental gain of 0.25 QALYs was estimated for GClb compared to R-Clb at additional cost of € 7357.85 per patient. Corresponding ICER was 29 436.00 € /QALY. The associated cost per relapse for G-Clb as first line therapy was significantly lower compared to R-Clb (G-Clb vs. R-Clb= 4815.6 € vs. 6946.1€). Sensitivity analyses showed the robustness of the base case results. The PSA demonstrated that the probability of cost effectiveness was 84% for G-Clb compared to R-Clb.

CONCLUSIONS:

G-Clb represents a cost - effective treatment strategy for unfit CLL patients in R.Macedonia.