Herceptin Trastuzumab Injection

1. Indications and Usage
Metastatic Breast Cancer: Indicated for the treatment of HER2-positive metastatic breast cancer. As a single agent for patients with metastatic breast cancer who have received one or more chemotherapy regimens; in combination with paclitaxel for patients who have not received chemotherapy.
Adjuvant Breast Cancer: Indicated for the adjuvant treatment of patients with node-positive HER2-positive breast cancer.
Metastatic Gastric Cancer: Indicated for the treatment of patients with HER2-positive metastatic gastric or gastroesophageal junction adenocarcinoma.
2. Dosage and Administration
Route of Administration: Intravenous infusion ONLY. It must not be administered as an intravenous bolus.
Recommended Dosage:
For weekly regimen: Initial dose of 4 mg/kg, followed by 2 mg/kg weekly.
For q3w regimen: Initial dose of 8 mg/kg, followed by 6 mg/kg every 3 weeks.
Administration Details: The initial infusion should be administered over 90 minutes. If the initial infusion is tolerated well, subsequent infusions can be administered over 30 minutes.
Preparation: The drug must be diluted in 0.9% Sodium Chloride Injection and should not be mixed with other drugs.
3. Mechanism of Action
HER2 Binding: Trastuzumab is a recombinant humanized monoclonal antibody that binds with high affinity to the extracellular domain of the HER2 receptor.
Tumor Suppression: It inhibits HER2 receptor signaling, accelerates HER2 receptor internalization and degradation, and mediates antibody-dependent cell-mediated cytotoxicity (ADCC) to kill tumor cells.
4. Safety and Warnings
Cardiotoxicity: Trastuzumab can cause cardiomyopathy and a significant decrease in left ventricular ejection fraction (LVEF). LVEF must be assessed before and periodically during treatment.
Infusion-Related Reactions: Severe and fatal infusion reactions, including bronchospasm and hypotension, may occur, particularly during the first infusion.
Embryo-Fetal Toxicity: Trastuzumab can cause fetal harm when administered to a pregnant woman, including oligohydramnios and skeletal deformities.
5. Adverse Reactions and Clinical Research
Most Common Adverse Reactions: Pyrexia, nausea, vomiting, diarrhea, asthenia/fatigue, headache, musculoskeletal pain, and infection.
Clinical Research Highlights: Clinical trials have demonstrated that trastuzumab significantly improves overall survival and response rates in HER2-positive breast and gastric cancers when combined with chemotherapy.
6. Drug Interactions
Anthracyclines: Concurrent use with anthracyclines significantly increases the risk of cardiotoxicity (heart failure or significant decline in LVEF).
Live Vaccines: Concurrent use with live vaccines may result in infection; live vaccines should be avoided during treatment.
7. Pharmaceutical Information
Chemical Composition: Active ingredient: Trastuzumab.
Appearance: Clear to slightly opalescent, colorless to pale yellow liquid.
Packaging: Available as lyophilized powder or solution in vials of various strengths.
Storage: Store in a refrigerator at 2°C to 8°C. Do not freeze or shake.