Trastuzumab (Trade name: Herceptin)
This is a monoclonal antibody that is used in treating HER2-positive breast cancer in early, locally advanced and metastatic stages. It is also sometimes used to treat metastatic stomach cancer, in combination with chemotherapy.
Side effects of Trastuzumab
The most commonly known side effects of Trastuzumab include:
- Infusion related symptoms such as fever, chills, flushing, fatigue, headache, hypotension, etc
- Cardiotoxicity in the form of shortness of breath, peripheral oedema, and decreased ventricular function
- Decreased count of white blood cells or WBCs (Myelosuppression)
- Lung toxicity in the form of increased cough, difficulty in breathing, sinusitis, pleural effusion, etc
Availability of Trastuzumab
Trastuzumab is available in the following commercial formats:
- 150 mg/single dose vial
- 420 mg/multi dose vial
Administration & dosage of Trastuzumab
Trastuzumab is administered intravenously. Trastuzumab is given on a three-weekly or weekly basis. In the three-weekly regimen for Trastuzumab, a loading dose of 8 mg/kg is given over 90 minutes followed by a maintenance dose of 6 mg/kg, given over 30-90 minutes, on a three weekly basis for 17 cycles.
In the weekly regimen for Trastuzumab, a loading dose of 4 mg/kg is given over 90 minutes, followed by a maintenance dose of 2 mg/kg, given over 30 minutes on a weekly basis for 52 weeks.
Patients with a pre-existing dysfunctional cardiac condition, and breastfeeding mothers should take precautions when using Trastuzumab.