Scientific Poster Session IV - Original Research

Original Research
  Tuesday, November 14, 2023
  08:30 AM–10:00 AM

Abstract

Introduction:

Biosimilars have emerged as other economic treatment choice besides originators. However, real-world evidence about utilization of trastuzumab originators and biosimilars was still limited in Asian population.

Research Question or Hypothesis:

This study aimed to evaluate the clinical prescription pattern of breast cancer patients receiving trastuzumab originators and biosimilars in Taiwan.

Study Design:

The study was a retrospectively observation study conducting by Chang Gung Research Database including five hospitals covering different areas of Taiwan.

Methods:

Breast cancer patients who newly receiving trastuzumab originators (Herceptin®) and biosimilars including Herzuma®, Kanjinti® and Ogivri® between January 2020 to April 2023 were included. We analyzed patients’ baseline demographics between originators and biosimilar groups, including age, tumor stage, Eastern Cooperative Oncology Group (ECOG) performance status, tumor markers and treatment type (i.e., neoadjuvant and adjuvant therapies). We described the patients’ characteristics by median and interquartile range (IQR) for continuous variables, and absolute and relative frequencies for categorical variables, respectively.

Results:

A total of 608 originator users and 41 biosimilar users were included. The age was similar between two groups (54.9 vs. 54.5 years, P = 0.85) For cancer stage, 77.5% biosimilar users were diagnosed as early stage (stage 0 to 2), while 55.5% originator users were in early stage. For available ECOG status, early stage biosimilar users were all scored as 0 while 91.7% originator users were scored as 0. For HER2 results, 100% biosimilar users and 96.1% originator users were HER2 positive. For treatment type, biosimilars were all prescribed in non-neoadjuvant therapy, and the percent of originators utilized in adjuvant, disease treatment and neoadjuvant therapy was 43.2%, 29.5% and 27.3%, respectively.

Conclusion:

Most of the breast cancer patients newly receiving trastuzumab biosimilars were attributed to early stage in Taiwan. Long-term follow up and larger number studies are warranted to compare the treatment results between trastuzumab originator and biosimilars in Asia.

Presenting Author

Yun Jung Tsai MS
Linkou Chang Gung Memorial Hospital

Authors

Kai-Cheng Chang PHD student
Linkou Chang Gung Memorial Hospital

Hui-Yu Chen MS
Linkou Chang Gung Memorial Hospital