Evaluation of Real-World Total Healthcare Costs Difference Between Subcutaneous and Intravenous Formulations of Pertuzumab and Trastuzumab in HER2+ Breast Cancer Patients

OBJECTIVES: The subcutaneous (SQ) formulations of anticancer drugs may reduce the need for vascular access devices and facilitate care in lower-resource settings, potentially lowering total healthcare costs (THCC). This study compares the average monthly THCC of SQ fixed-dose combination [FDC] Pertuzumab and Trastuzumab (PH) with intravenous (IV) PH among patients with breast cancer (BC) over a one-year period or a maximum of 18 cycles.
METHODS: We retrospectively analyzed data from adult women with HER2+ BC identified between 01/01/2021 and 12/31/2023 in the IQVIA PharMetricsⓇ Plus database. Patients were grouped into neoadjuvant (NEO), adjuvant-only (ADJ), and metastatic (mBC) cohorts. Targeted maximum likelihood estimation with machine learning was used to calculate average monthly THCC differences across the three cohorts adjusting for age, payer type, plan type, CCI, baseline total cost.
RESULTS: A total of 1,871 patients were included , with 70.8% in the NEO cohort, 16.5% in the ADJ cohort, and 12.7% in the mBC cohort. In the NEO cohort (1,325 patients) , 92.5% received PH IV, and 7.5% PH FDC. In the ADJ cohort (n=309), 89% received PH IV and 11% PH FDC. Among mBC patients (n= 237), 92.4% received PH IV, while 7.6% received PH FDC. Average monthly THCC were lower for the PH FDC compared to PH IV in all cohorts, with a monthly cost difference of $3,346 (95%CI=$2,318, $4,376) in the NEO, $5,227 ($3,349, $7,107) in the ADJ, and $5,585 ($3,485, $7,684) in the mBC cohorts.
CONCLUSIONS: PH FDC (SQ) is associated with significantly lower average monthly THCC compared to PH IV across different BC cohorts, with projected potential annual savings ranging from $59,637 in eBC (4 NEO + 14 ADJ cycles) to $62,724 in mBC (18 cycles)