Herzuma

Herzuma is a trastuzumab‑based solution for injection supplied as an intravenous drug. It contains the monoclonal antibody trastuzumab, a HER2 receptor antagonist, and is marketed in the European Union as a prescription‑only product. The formulation is designed for infusion in clinical settings and is used in the treatment of cancers that overexpress the HER2 protein. Herzuma provides a biosimilar option to reference trastuzumab therapies for oncologists.

Herzuma is indicated for patients whose tumors show over‑expression of the human epidermal growth factor receptor 2 (HER2).

- HER2‑positive breast cancer in early or metastatic settings. - HER2‑positive gastric or gastro‑esophageal junction adenocarcinoma. - Combination with chemotherapy regimens as part of first‑line therapy. - Use in neoadjuvant or adjuvant treatment protocols where HER2 targeting is required.

Adverse reactions to Herzuma vary in frequency and severity.

Common: - Infusion‑related reactions (fever, chills, nausea). - Fatigue or asthenia. - Diarrhea or abdominal discomfort. - Rash or mild skin irritation. - Transient elevations in liver enzymes.

Serious: - Cardiac dysfunction, including decreased left ventricular ejection fraction. - Severe infusion‑related anaphylaxis. - Pulmonary toxicity such as interstitial pneumonitis. - Thromboembolic events. - Severe neutropenia or thrombocytopenia.

Healthcare providers should assess patient history and monitor for specific risks before and during Herzuma therapy.

- Evaluate baseline cardiac function; repeat assessments during treatment. - Use caution in patients with pre‑existing pulmonary disease. - Monitor liver function tests periodically. - Assess for signs of infection; avoid use in active uncontrolled infections. - Consider dose adjustments in patients with severe hepatic impairment. - Counsel patients on the possibility of infusion reactions and advise prompt reporting of symptoms.

Herzuma may interact with other agents that affect cardiac function or immune response.

Avoid: - Concurrent use of anthracyclines due to increased cardiotoxicity risk. - Live vaccines during treatment because of immunosuppression.

Use with caution: - Other HER2‑targeted therapies (e.g., pertuzumab) may amplify cardiac effects. - Medications that prolong QT interval. - Systemic corticosteroids, which may mask infusion reactions. - Drugs that cause hepatic enzyme induction or inhibition, potentially altering trastuzumab clearance.