Cost-effectiveness of blinatumomab for the treatment of B-precursor acute lymphoblastic leukemia pediatric patients with high-risk first-relapse in Mexico

Background: Blinatumomab is a CD3/CD19-directed bispecific T-cell engager molecule that engages T cells to lyse CD19-expressing B cells. Based on a multicenter, open-label, phase 3, randomized clinical trial (Clinical Trials ID: NCT02393859), we aimed to evaluate the cost-effectiveness (CE) of blinatumomab compared to standard consolidation chemotherapy (SC) for the treatment of pediatric patients with high-risk first-relapsed Philadelphia chromosome-negative B-cell precursor acute lymphoblastic leukemia (B-ALL) from a Mexico healthcare payer perspective. Methods: A decision-analytic model, a partitioned survival model, was used to estimate the life-years (LYs) and costs over a lifetime horizon. We assumed that patients who remained alive beyond a 5-year period were cured. To account for the lingering impacts of cancer treatment, an excess mortality rate was incorporated into the model. Event-free survival (EFS) and overall survival (OS) were estimated by fitting mixture-cure and standard parametric survival distributions to the time-to-event data from the phase 3 trial. The model accounted for treatment costs, adverse event costs, follow-up costs, subsequent allogeneic hematopoietic stem cell transplantation (alloHSCT) costs, and subsequent treatment costs. Results: Blinatumomab was associated with a lifetime gained of 5.11 years at an incremental cost of $621,111 MXN, relative to SC. The ICER for blinatumomab vs Standard of care was estimated to be $121,526 MXN/LY gained in the base case. Cost-effectiveness was sensitive to varying the time horizon. Blinatumomab had a probability of 99 % of being cost-effective, relative to SC, at the willingness to pay threshold defined in Mexico. Limitations: Health-related quality of life values were not included in the analysis and therefore we did not estimate the quality-adjusted life-years gained. Conclusions: Blinatumomab was associated with greater benefit in terms of OS and EFS relative to SC. Probabilistic, deterministic, and scenario analyses indicate that blinatumomab represents the best value for money. Therefore, blinatumomab administered as part of consolidation therapy in B-ALL pediatric patients with highrisk first relapse is a cost-effective option.