The European Commission (EC) has approved trazimera (trastuzumab), Pfizer’s biosimilar to Roche’s Herceptin, making it Pfizer’s first oncology biosimilar to be approved in Europe.

Pfizer’s biosimilar is indicated for the same conditions as its reference product Herceptin: human epidermal growth factor receptor 2 (HER2) overexpressing breast cancer and HER2 overexpressing metastatic gastric or gastroesophageal junction adenocarcinoma.

The drug is a monoclonal antibody biosimilar of Herceptin. It works by targeting HER2, a protein found on the surface of some cancer cells, which stimulates those cells to divide and grow. Trazimera binds to HER2 protein and blocks the receptor, thereby preventing cell division and growth.

The EC’s decision follows a recommendation by the European Medicines Agency’s Committee for Medical Products for Human Use (CHMP) in June 2018, which was based upon a comprehensive submission package centred around data from the Reflections B327-02 clinical trial.

CHMP concluded that trazimera was similar to Herceptin in terms of efficacy, safety, immunogenicity and pharmacokinetics and found no clinically significant differences between the two drugs.

Pfizer Essential Health Europe, Africa, Middle East and Biosimilars global president Richard Blackburn said: “The approval of trazimera, Pfizer’s first oncology biosimilar, is another significant step in our quest to introduce more treatment options for patients in Europe. Pfizer is investing in developing and launching a range of biosimilars which can help to reduce healthcare costs and increase patient access to important medicines.”

The US Food and Drug Administration (FDA) sent a complete response letter in response to Pfizer’s biologics license application for trazimera in April this year stating that it needed more technical information in order to approve the biologic. The FDA emphasised its decision was not linked to any issues with safety or clinical data.

Pfizer has said it will work closely with the FDA to address its concerns and gain the regulator’s approval for trazimera.