Ontruzant Trastuzumab 420-mg Multidose Vial Approved by FDA

The FDA has approved a 420-mg multidose vial of Samsung Bioepis’ trastuzumab biosimilar Ontruzant, which is yet to be launched in the United States.

Ontruzant is indicated for the adjuvant treatment of HER2-overexpressing breast cancer, metastatic breast cancer, and metastatic gastric cancer or gastroesophageal junction adenocarcinoma in patients who have not received prior treatment for metastatic disease.

The biosimilar was first approved as a 150-mg single-dose vial by the FDA in January 2019 across all indications for the reference product, Herceptin.

In the United States, Ontruzant, when launched, would compete with 4 other trastuzumab biosimilars, Herzuma, Trazimera, Ogivri, Kanjinti, as well as Herceptin. Herzuma was launched this month; Trazimera in February 2020; Ogivri in December 2019; and Kanjinti, the first biosimilar trastuzumab to launch, in July 2019.

Amgen reported fourth quarter 2019 US revenues of $79 million for Kanjinti, up from $39 million in the previous quarter. The product launched at a 15% discount to Roche-Genentech’s Herceptin, which has annual sales of roughly $7 billion and costs about $70,000 for a full course of treatment.

In tandem with the Ontruzant announcement, Samsung Bioepis said the biosimilar will be marketed and distributed in the United States by Merck, which intends to spin off products from its biosimilars business, including Ontruzant, into a new independent, publicly traded company. This spinoff is expected to occur in the first half of 2021, and until that time Merck will handle the commercialization of Ontruzant.

The European Commission approved Ontruzant 150 mg in November 2017. The 420-mg vial was approved for sales by the European Medicines Agency in March 2019.