Cost-Effectiveness Analysis of Larotrectinib and Entrectinib for Adult Patients with NTRK Gene Fusion-Positive Breast Cancer

OBJECTIVES: The rising prevalence of cancer has led to the development of drugs such as larotrectinib and entrectinib, targeting NTRK gene fusions. These drugs offer improved effectiveness but also increased costs compared to conventional treatments. Evaluating the cost-effectiveness of these new therapies is essential to ensure the optimal use of resources. This study evaluated the cost-effectiveness of larotrectinib versus entrectinib in the treatment of adult patients with NTRK gene fusion-positive breast cancer.

METHODS: A cost-effectiveness analysis was conducted using data from the FDA website, IBM Micromedex, and existing literature. The analysis accounted for direct medical costs, including the drugs' prices (wholesale acquisition cost), administration, management of side effects, and overall medical treatment costs for breast cancer. Costs were reported in November 2023 dollars. The main outcome measured was the quality-adjusted life year (QALY). A multivariate sensitivity analysis was also performed using Monte Carlo simulation.

RESULTS: Larotrectinib showed higher costs than entrectinib ($651,718 vs. $397,970) and a greater number of QALYs (5.8 vs. 2.3). The cost of the drug product was the most significant contributor to the treatment expense for both drugs. Larotrectinib resulted in an additional $72,312 per QALY gained compared to entrectinib. Sensitivity analysis indicate that the study's findings were stable and not significantly affected by variations in the parameters of the analysis. These results should be interpreted in the context of the limited number of patients assessed in clinical trials for breast cancer, the brief duration of the available trials, and the absence of direct comparative trials evaluating the outcomes of both drugs.

CONCLUSIONS: Larotrectinib is costlier yet more effective than entrectinib for the treatment of adult patients with NTRK gene fusion-positive breast cancer. The incremental cost-effectiveness ratio (ICER) per QALY gained was below the often-cited societal threshold of $75,000.