Presentation (CTI)

OBJECTIVES: Trastuzumab Deruxtecan significantly improves survival status of patients with HER2-positive advanced breast cancer. Although approved for use in China in February 2023, it is not yet included in the China National Reimbursement Drug List (NRDL). This study analyzes real-world data to evaluate medication use, compliance, and dosage, assessing the disease burden and unmet needs.
METHODS: This retrospective, non-interventional cohort study examined medical records from hospitalized patients treated with Trastuzumab Deruxtecan, collected from grade III hospitals in 14 cities across 12 provinces. The index date was the date of first administration of Trastuzumab Deruxtecan, with a 6-month baseline to ensure no prior use. The study included 377 cases, integrating prescription and medication charge records for dosage accuracy.
RESULTS: The average patient weight was 57.45 kg, with 57.82% weighing less than 60 kg. The proportions of patients using 2 or 3 vials per cycle were 32.05% and 46.15%, respectively, while 15.38% used 4 vials, with no patients using more than 4 per cycle. On average, 2.71 vials were used per cycle, with an average single dose of 251.55 mg. The average dose per kg per prescription was 4.39 mg, below the recommended 5.4 mg/kg. Only 13.00% of the patients adhered fully to the recommended dosing regimen. The average number of treatment cycles per patient was 6.48, with an average interval of 28.25 days between the first and second treatments, and around 24.20 to 30.14 days between subsequent treatments. The average interval from the first to the last treatment was 104.54 days.
CONCLUSIONS: Treatment compliance was acceptable (more than 6 cycles). However, the administered dose was lower than recommended, and treatment intervals were longer than the recommended 21 days. A small percentage of patients received standard treatment. Further research is necessary to understand the deviations in treatment patterns and their impact on prognosis.