What is Herzuma (trastuzumab-pkrb)?

Herzuma (trastuzumab-pkrb) is a biosimilar of trastuzumab (trastuzumab, Herceptin). According to the U.S. Food and Drug Administration (FDA), a biosimilar is a biological product that is highly similar to an existingFDA-approved reference product without clinically meaningful differences. Herzuma is the second approved biosimilar of trastuzumab.

After Herzuma is approved for marketing, it is suitable for the adjuvant treatment of HER2-overexpressing cancers that are node-positive or node-negative (ER/PR negative or have a high-risk feature). It can be used as part of a regimen consisting of doxorubicin, cyclophosphamide, and paclitaxel or docetaxel; as part of a regimen of docetaxel and carboplatin; and as a single agent in the adjuvant treatment of breast cancer after multimodal anthracycline-based therapy.

Herzumacan be used in combination with paclitaxelfor the first-line treatment of HER2-overexpressing metastatic breast cancer (MBC); it can also be used as a single agent for the treatment of HER2-overexpressing breast cancer in patients who have received one or more chemotherapy regimens for metastatic disease. Herzumacan be used in combination with cisplatin and capecitabine or 5-fluorouracil for the treatment of patients with HER2-overexpressing metastatic gastric or gastroesophageal junction adenocarcinoma (MGC) who have not received previous treatment for metastatic disease.

Doctors will select patients suitable for Herzuma treatment based on HER2 protein overexpression or HER2 gene amplification in tumor specimens. The evaluation of HER2 protein overexpression and HER2 gene amplification should be certified by Competent laboratories use an FDA-approved test specific for breast or gastric cancer. Due to differences in gastric versus breast histopathology, including incomplete membrane staining and more frequent heterogeneous expression of HER2 in gastric cancer, evaluation of HER2 protein overexpression and HER2 gene amplification in metastatic gastric cancer should be performed using an FDA-approved test specific for gastric cancer.