Herzuma 440 mg Powder for Concentrate for Solution for Infusion

Herzuma 440 mg Powder for Concentrate for Solution for Infusion contains trastuzumab 440mg, a biosimilar monoclonal antibody that targets the HER2 (human epidermal growth factor receptor 2) protein. It is used in the treatment of HER2-positive breast cancer and certain cases of HER2-positive metastatic gastric (stomach) cancer, and is given only as an intravenous infusion under specialist oncology care.

Trastuzumab works by binding to the HER2 receptor on the surface of cancer cells that overexpress this protein, blocking the growth signals that drive tumour cell division and marking these cells for destruction by the body’s immune system.

Trastuzumab is a humanised monoclonal antibody that binds specifically to the extracellular domain of the HER2 receptor. This blocks HER2-driven signalling pathways that promote uncontrolled cancer cell growth and survival, and also flags HER2-overexpressing cells for attack by immune cells (antibody-dependent cellular cytotoxicity).

Herzuma 440 mg Powder for Concentrate for Solution for Infusion is reconstituted from powder and given only as an intravenous infusion by trained healthcare professionals in a hospital or specialist oncology infusion setting – it is never self-administered at home. You will be closely monitored during and for a period after each infusion for signs of an infusion-related reaction, and your heart function will be assessed regularly throughout treatment.

Herzuma 440 mg Powder for Concentrate for Solution for Infusion is dosed entirely on an individualised basis by the treating oncologist, calculated according to body weight, cancer type and stage, treatment protocol (including whether it is combined with chemotherapy), and the patient’s response and tolerance over time. There is no standard self-directed dosing schedule – your oncology team determines and administers every dose and the interval between infusions.

Use this product before the expiry date stated on the packaging. Do not use the medicine if the expiry date has passed.

Store in a refrigerator (2-8°C). Do not freeze. This product is handled and stored by the hospital or infusion centre pharmacy – patients do not store or reconstitute this medicine themselves.

• Infusion-related reactions during or shortly after the infusion (fever, chills, nausea)
• Fatigue and general weakness
• Diarrhoea or other gastrointestinal upset
• Headache
• Serious: signs of heart problems (shortness of breath, swelling of the legs or ankles, irregular heartbeat, sudden weight gain) or a severe infusion reaction (difficulty breathing, wheezing, severe drop in blood pressure) require immediate medical attention – these are monitored closely by your oncology team

• Known hypersensitivity to trastuzumab, other murine (mouse) proteins, or any ingredient in this product
• Severe dyspnoea (breathlessness) at rest due to complications of advanced malignancy, or requiring supplementary oxygen therapy
• Use with caution or under specialist review in patients with pre-existing significant heart disease or reduced heart function
• Pregnancy – trastuzumab can cause harm to the developing baby and effective contraception is advised during and after treatment

• Anthracycline chemotherapy agents (e.g. doxorubicin) combined with or given close to trastuzumab significantly increase the risk of cardiotoxicity – your oncologist carefully sequences and monitors these treatments
• Other chemotherapy agents given as part of the same treatment protocol may have their own separate interaction profiles managed by your oncology team
• No specific food interactions are established, but your oncology team will advise on general nutrition during cancer treatment

• This medicine is given only in a hospital or specialist oncology infusion setting under close medical supervision – it is never self-administered
• Attend every scheduled cardiac assessment (such as an echocardiogram or MUGA scan) before and during treatment, as heart function is monitored throughout
• Report any new shortness of breath, swelling, or irregular heartbeat to your oncology team promptly, even between scheduled visits
• Tell your oncology team about any prior or planned anthracycline-based chemotherapy
• Keep all infusion appointments as scheduled, since consistent timing is part of the treatment protocol
• Use effective contraception during treatment and for the period advised by your oncologist afterwards