Hertraz Dosage/Direction for Use

HER2 testing is mandatory prior to initiation of therapy (see Pharmacology: Pharmacodynamics under Actions and Precautions). Trastuzumab treatment should only be initiated by a physician experienced in the administration of cytotoxic chemotherapy (see Precautions) and should be administered by a healthcare professional only.
It is important to check the product labels to ensure that the correct formulation is being administered to the patient, as prescribed. Trastuzumab should be administered via an intravenous infusion only and is not intended for subcutaneous administration.
Posology: Metastatic Breast Cancer: Three-Weekly Schedule: 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.
Weekly Schedule: 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.
Administration in Combination with Paclitaxel or Docetaxel: As per the published literature on another trastuzumab product, in the pivotal trials, paclitaxel or docetaxel was administered the day following the first dose of trastuzumab and immediately after the subsequent doses of trastuzumab if the preceding dose of trastuzumab was well tolerated.
Administration in combination with an aromatase inhibitor: As per the published literature on another trastuzumab product, in the pivotal trial from day 1 trastuzumab and anastrozole were administered. There were no restrictions on the relative timing of trastuzumab and anastrozole at administration.
Early Breast Cancer: Three-Weekly and Weekly Schedule: 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 (see Pharmacology: Pharmacodynamics under Actions).
Metastatic Gastric Cancer: Three-Weekly Schedule: The recommended initial loading dose is 8 mg/kg body weight and the recommended maintenance dose at three-weekly intervals is 6 mg/kg body weight, beginning three weeks after the loading dose.
Breast Cancer and Gastric Cancer: Duration of Treatment: Patients with MBC or MGC  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 (see Pharmacology: Pharmacodynamics under Actions).
Dose Reduction: As per the published literature on another trastuzumab product, 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) drops ≥10 ejection fraction (EF) 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 declined further, or 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.
Missed Doses: If the patient misses 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 given as soon as possible. Do not wait until the next planned cycle. Subsequent maintenance doses (weekly regimen: 2 mg/kg; three-weekly regimen: 6 mg/kg respectively) should then be given according to the previous schedule.
If the patient misses a dose of trastuzumab by more than one week, a re-loading dose of trastuzumab should be given over approximately 90 minutes (weekly regimen: 4 mg/kg; three-weekly regimen: 8 mg/kg). Subsequent trastuzumab maintenance doses (weekly regimen: 2 mg/kg; three-weekly regimen 6 mg/kg respectively) should then be given (weekly regimen: every week; three-weekly regimen every 3 weeks) from that point.
Special Populations: Dedicated pharmacokinetic studies in older people and those with renal or hepatic impairment have not been carried out. As per the published literature on another trastuzumab product, in a population pharmacokinetic analysis, age and renal impairment were not shown to affect trastuzumab disposition.
Paediatric Population: There is no relevant use of trastuzumab in the paediatric population.
Administration: Trastuzumab loading dose should be administered as a 90-minute intravenous infusion. Do not administer as an intravenous push or bolus. Only a healthcare provider should administer Trastuzumab intravenous infusion. Preparations 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 (see Precautions and Adverse Reactions). 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.
If the initial loading dose was well tolerated, the subsequent doses can be administered as a 30-minute infusion.