Active Ingredient: Trastuzumab
Trastuzumab is indicated for the treatment of adult patients with HER2 positive metastatic breast cancer (MBC):
Trastuzumab is indicated for the treatment of adult patients with HER2 positive early breast cancer (EBC).
Trastuzumab should only be used in patients with metastatic or early breast cancer whose tumours have either HER2 overexpression or HER2 gene amplification as determined by an accurate and validated assay.
For this indication, competent medicine agencies globally authorize below treatments:
For:
Regimen A: Intravenous, 8 milligrams trastuzumab per kilogram of body weight, one dose, over the duration of 3 weeks. Afterwards, intravenous, 6 milligrams trastuzumab per kilogram of body weight, once every 3 weeks.
Regimen B: Intravenous, 4 milligrams trastuzumab per kilogram of body weight, one dose, over the duration of 1 week. Afterwards, intravenous, 2 milligrams trastuzumab per kilogram of body weight, once weekly.
The recommended initial loading dose is 8 mg/kg body weight. The recommended maintenance dose at three-weekly intervals is 6 mg/kg body weight, beginning three weeks after the loading dose.
The recommended initial loading dose of trastuzumab is 4 mg/kg body weight. The recommended weekly maintenance dose of trastuzumab is 2 mg/kg body weight, beginning one week after the loading dose.
In the pivotal trials (H0648g, M77001), paclitaxel or docetaxel was administered the day following the first dose of trastuzumab (for dose, see the Summary of Product Characteristics (SmPC) for paclitaxel or docetaxel) and immediately after the subsequent doses of trastuzumab if the preceding dose of trastuzumab was well tolerated.
In the pivotal trial (BO16216) trastuzumab and anastrozole were administered from day 1. There were no restrictions on the relative timing of trastuzumab and anastrozole at administration (for dose, see the SmPC for anastrozole or other aromatase inhibitors).
As a three-weekly regimen the recommended initial loading dose of trastuzumab is 8 mg/kg body weight. The recommended maintenance dose of trastuzumab at three-weekly intervals is 6 mg/kg body weight, beginning three weeks after the loading dose.
As a weekly regimen (initial loading dose of 4 mg/kg followed by 2 mg/kg every week) concomitantly with paclitaxel following chemotherapy with doxorubicin and cyclophosphamide.
Patients with MBC should be treated with trastuzumab until progression of disease. Patients with EBC should be treated with trastuzumab for 1 year or until disease recurrence, whichever occurs first; extending treatment in EBC beyond one year is not recommended.
No reductions in the dose of trastuzumab were made during clinical trials. Patients may continue therapy during periods of reversible, chemotherapy-induced myelosuppression but they should be monitored carefully for complications of neutropenia during this time. Refer to the SmPC for paclitaxel, docetaxel or aromatase inhibitor for information on dose reduction or delays.
If left ventricular ejection fraction (LVEF) percentage drops โฅ10 points from baseline AND to below 50%, treatment should be suspended and a repeat LVEF assessment performed within approximately 3 weeks. If LVEF has not improved, or has declined further, or if symptomatic congestive heart failure (CHF) has developed, discontinuation of trastuzumab should be strongly considered, unless the benefits for the individual patient are deemed to outweigh the risks. All such patients should be referred for assessment by a cardiologist and followed up.
If the patient has missed a dose of trastuzumab by one week or less, then the usual maintenance dose (weekly regimen: 2 mg/kg; three-weekly regimen: 6 mg/kg) should be administered as soon as possible. Do not wait until the next planned cycle. Subsequent maintenance doses should be administered 7 days or 21 days later according to the weekly or three-weekly schedules, respectively.
If the patient has missed a dose of trastuzumab by more than one week, a re-loading dose of trastuzumab should be administered over approximately 90 minutes (weekly regimen: 4 mg/kg; three-weekly regimen: 8 mg/kg) as soon as possible. Subsequent trastuzumab maintenance doses (weekly regimen: 2 mg/kg; three-weekly regimen 6 mg/kg respectively) should be administered 7 days or 21 days later according to the weekly or three-weekly schedules respectively.
Trastuzumab is for intravenous use. The loading dose should be administered as a 90-minute intravenous infusion. Administration as an intravenous push or bolus is prohibited. Trastuzumab intravenous infusion should be administered by a health-care provider prepared to manage anaphylaxis and an emergency kit should be available. Patients should be observed for at least six hours after the start of the first infusion and for two hours after the start of the subsequent infusions for symptoms like fever and chills or other infusion-related symptoms. Interruption or slowing the rate of the infusion may help control such symptoms. The infusion may be resumed when symptoms abate.
If the initial loading dose was well tolerated, the subsequent doses can be administered as a 30-minute infusion.
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