22 March 2019 - - South Korea-based Samsung Bioepis Co., Ltd has received findings of a three-year follow-up study comparing biosimilar Ontruzant (trastuzumab) and reference medicine trastuzumab in early or locally advanced HER2-positive breast cancer, the company said.

The data, which show comparable overall survival and cardiac safety, were presented at the 16th St. Gallen International Breast Cancer Conference 2019 taking place in Vienna, Austria.

Participants enrolled in an initial Phase III study 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 these participants (186 in the biosimilar trastuzumab group and 181 in the reference medicine group) 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.

Overall survival was 97% in the biosimilar trastuzumab group and 93.6% in the reference medicine group (HR 0.39, 95% CI, 0.14-1.12). Event-free survival was 92.5% in the biosimilar trastuzumab group and 86.3% in the reference medicine group (HR 0.49, 95% CI, 0.26-0.91).

The incidence of cardiac events was rare for both treatment groups throughout the three-year follow-up period. There were three cases of asymptomatic significant left ventricular ejection fraction decrease (biosimilar trastuzumab, n=1; reference medicine, n=2), with all patients recovering with LVEF ≥ 50%.

There were no cases of symptomatic congestive heart failure, cardiac death or other significant cardiac conditions reported in either group.

Ontruzant (trastuzumab) 150 mg was granted the European Commission Marketing Authorization in November 2017 and was approved by the US Food and Drug Administration in January 2019. In February 2019, the European Medicines Agency's Committee for Medicinal Products for Human Use adopted a positive opinion for a 420 mg vial presentation of Ontruzant.

With the adoption of CHMP's positive opinion for Ontruzant 420 mg vial presentation, Ontruzant will be available in two vial sizes in Europe, providing clinics with greater convenience and flexibility than the 150 mg vial presentation alone.

Established in 2012, Samsung Bioepis is a biopharmaceutical company committed to realizing healthcare that is accessible to everyone.

Through innovations in product development and a firm commitment to quality, Samsung Bioepis aims to become the world's leading biopharmaceutical company.

Samsung Bioepis continues to advance a broad pipeline of biosimilar candidates that cover a spectrum of therapeutic areas, including immunology, oncology and ophthalmology. Samsung Bioepis is a joint venture between Samsung BioLogics and Biogen.