Vivitra^TM (Trastuzumab) is a humanized monoclonal anti-HER2 antibody. It has been expressed in Chinese Hamster Ovary (CHO) cell line. It comprises of 1328-amino acids; glycoprotein. It has molecular weight of 148 kDa (approx.)¹

Mechanism of Action

Vivitra^TM (Trastuzumab) binds with high affinity and specificity to an epitope located in the extracellular sub-domain IV of HER2 present juxtaposed to the cell membrane region. Binding of Vivitra^TM (Trastuzumab) to HER2 inhibits HER2 signalling and prevents the proteolytic cleavage of its extracellular domain, leading to an inhibition of proliferation of HER2 overexpressing human tumor cells.¹

Vivitra^TM (Trastuzumab) is also known to carry out its function via an immune effector mechanism, ADCC (antibody-dependent cell-mediated cytotoxicity), by binding to HER2 overexpressing cancer cells in the presence of NK(natural killer) cells.¹

Indications

Metastatic Breast Cancer (MBC):

Vivitra^TM (Trastuzumab) is indicated for the treatment of patients with HER2 overexpressing metastatic breast cancer. Vivitra^TM (Trastuzumab) is also indicated in combination with aromatase inhibitor for the treatment of patients with HER2 overexpressing and hormone receptor-positive metastatic breast cancer.

Early Breast Cancer (EBC):

Vivitra^TM (Trastuzumab) is indicated for the treatment of patients with HER2 overexpressing early breast cancer following surgery, chemotherapy (neo adjuvant or adjuvant) and radiotherapy (if applicable). Vivitra^TM (Trastuzumab) is also indicated for adjuvant treatment of patients with HER2 overexpressing node positive or node negative breast cancer (i) as part of treatment regimen comprising doxorubicin, cyclophosphamide, and either paclitaxel or docetaxel (ii) with docetaxel and carboplatin.

Metastatic Gastric Cancer (MGC):

Vivitra^TM (Trastuzumab) is indicated for the treatment of patients with HER2 overexpressing metastatic gastric or gastroesophageal junction adenocarcinoma in combination with capecitabine or 5- fluorouracil and cisplatin who have not received prior anti-cancer treatment for their metastatic disease.

Dosage and Administration¹

Cycle	Dose	Route/Duration
Weekly
Loading dose	4 mg/kg	I.V. infusion over 90 minutes
Subsequent dose	2 mg/kg	I.V. infusion over 30 minutes
3 Weekly
Loading dose	8 mg/kg	I.V. infusion over 90 minutes
Subsequent dose	6 mg/kg	I.V. infusion over 30 minutes

 

Special Warnings and Precautions for Use¹

Cardiomyopathy: Vivitra^TM (Trastuzumab) can result in sub-clinical and clinical cardiac failure manifesting as Congestive heart failure (CHF), and decreased Left ventricular ejection factor (LVEF), with greatest risk when administered concurrently with anthracyclines. Evaluate cardiac function prior to and during treatment. Discontinue Vivitra^TM (Trastuzumab) for cardiomyopathy.

Infusion reactions, Pulmonary toxicity: Discontinue Vivitra^TM (Trastuzumab) for anaphylaxis, angioedema, interstitial pneumonitis, or acute respiratory distress syndrome.

Embryo-Fetal Toxicity: Exposure to Vivitra^TM (Trastuzumab) during pregnancy can result in oligohydramnios, in some cases complicated by pulmonary hypoplasia and neonatal death.

Most Common Adverse Events with Vivitra^TM (Trastuzumab): These are anemia, neutropenia, thrombocytopenia, diarrhoea, nausea, vomiting, stomatitis, pyrexia, asthenia.

References

1. Vivitra^TM (Trastuzumab) Prescribing Information