The a three-year follow-up study comparing biosimilar Ontruzant (trastuzumab) to a reference version - Herceptin - has found that the drug shows comparable overall survival and cardiac safety in early or locally advanced HER2-positive breast cancer.

The Phase III study patients received eight cycles of the biosimilar trastuzumab or the reference medicine concurrently with chemotherapy in the neoadjuvant setting. Following surgery, they received additional 10 cycles of the biosimilar trastuzumab or the reference medicine.

After completion of therapy, 367 of the participants were enrolled in the follow-up study. Median follow-up from initiation of study treatment was 40.8 months in the biosimilar trastuzumab group and 40.5 months in the reference medicine group with overall survival being 97% in the biosimilar trastuzumab group and 93.6% in the reference medicine group. There were no cases of symptomatic congestive heart failure, cardiac death or other significant cardiac conditions reported in either group.

“With the development of our biosimilar trastuzumab, we aimed to make one of the mainstays of modern cancer therapy more accessible for more people more quickly, and these long-term data underline the importance of that aim,” said Chul Kim, Senior Vice President and Head of Clinical Sciences Division, Samsung Bioepis. “We are committed to increasing access to high-quality, life-changing oncology medicines through the development of biosimilars to address some of oncology’s most pressing challenges.”

The biosimilar has already been granted the European Commission (EC) Marketing Authorisation in November 2017 and was approved by the U.S. Food and Drug Administration (FDA) in January 2019.