Margetuximab Versus Trastuzumab in Patients With Advanced Breast Cancer: A Cost-effectiveness Analysis

In the current study, a 3-state Markov model was developed to simulate the disease process of patients with HER-2 positive advanced breast cancer, and concluded that margetuximab plus chemotherapy is not cost-effective. Background: In the international, randomized, open-label, phase III study SOPHIA trial, margetuximab plus chemother-apy showed improved progression-free survival (PFS), and overall survival (OS) compared with trastuzumab plus chemotherapy. This study aimed to investigate whether margetuximab plus chemotherapy is cost-effective compared with trastuzumab plus chemotherapy in pretreated patients with ERBB2-positive advanced breast cancer. Materials and Methods: The clinical data for this model was derived from the SOPHIA trial. Costs and utility were either derived from the standard fee database or extracted from previously published literature. A three-state Markov model was developed to simulate the disease process of patients with advanced breast cancer. One-way sensitivity analyses were conducted to investigate the impact of variables in the analysis model. Probabilistic sensitivity analysis was performed based on 10,000 Monte-Carlo simulations. A subgroup analysis was performed to test whether margetuximab is cost-effective in CD16A-158F allele carriers. Results: Margetuximab plus chemotherapy provided an incremental 0.04 QALYs with an incremental cost of $66,109.78, compared with the trastuzumab plus chemotherapy, resulting in the incremental cost-effectiveness ratio (ICER) of $1,486,442.35/QALY, which exceeded the willingness to pay (WTP) threshold. While in the CD16A-158F allele carriers subgroup, the ICER decreased to $592,669.73/QALY. The variance of the utility of PFS state, costs of margetuximab, and utility of progressive disease state were the most influential factors in the sensitivity analysis. Conclusion: Under current WTP threshold, margetuximab plus chemotherapy is not cost-effective compared with trastuzumab plus chemotherapy in pretreated patients with ERBB2-positive advanced breast cancer. Selecting CD16A-158F allele carriers might be a considerable option to optimize the cost-effectiveness of margetuximab.