Enhertu Warning and Precautions

Enhertu (Trastuzumab) is an FDA-approved medicine which is recommended for treating patients with unresectable or metastatic HER2-positive breast cancer, unresectable or metastatic HER2-low (IHC 1+ or IHC 2+/ISH-) breast cancer, unresectable or metastatic non-small cell lung cancer (NSCLC) and locally advanced or metastatic HER2-positive gastric/ gastroesophageal junction (GEJ) adenocarcinoma. The FDA approved this drug in 2019. 

Warnings and Precautions

Interstitial Lung Disease/Pneumonitis

The patients taking the medicine Enhertu have reports of severe, life-threatening, or fatal interstitial lung disease (ILD), including pneumonitis. 

One should advise patients to immediately report cough, dyspnea, fever, and any new or worsening respiratory symptoms. Healthcare professionals should monitor patients for signs and symptoms of ILD. One should promptly investigate evidence of ILD, and one should evaluate patients with suspected ILD by radiographic imaging. Consider consultation with a pulmonologist.

Neutropenia

There is severe neutropenia, including febrile neutropenia, can occur in patients treated with Enhertu injection. One should monitor complete blood counts before initiation of Trastuzumab, before each dose, and as clinically indicated. Trastuzumab may require dose interruption or reduction based on the severity of neutropenia. 

Left Ventricular Dysfunction

There were reports that patients treated with the medicine Enhertu might be at increased risk of developing left ventricular dysfunction LVEF). Left ventricular ejection fraction decrease has been observed with anti-HER2 therapies, including Trastuzumab.

Patients who are treated with Trastuzumab might be at increased risk of developing LVEF. A left ventricular ejection fraction (LVEF) decrease has been observed with anti-HER2 therapies, including Enhertu.

Embryo-Fetal Toxicity

As per the mechanism of action, Enhertu 100 mg can cause fetal harm when administered to a pregnant woman. Healthcare professionals advise not females of reproductive potential to use the effective contraceptive method during treatment and for 7 months, followed by the last dose of Enhertu (Trastuzumab).

NOTE

One should consult the doctor before taking the medicine Enhertu (Trastuzumab) and discuss the patient’s medical history.