Indications
Perjeta (pertuzumab) is a HER2/neu receptor antagonist. It is used in two situations, and in both it is given together with Trastuzumab and docetaxel. The first is HER2-positive metastatic breast cancer (MBC), in patients who have not received anti-HER2 therapy or chemotherapy for their metastatic disease before. The second is neoadjuvant treatment, meaning treatment given before surgery. It is for patients with HER2-positive breast cancer that is locally advanced, inflammatory, or early stage (either greater than 2 cm in diameter or node positive), and it forms part of a complete treatment regimen for early breast cancer. This use is based on an improvement in pathological complete response rate. There are no data showing an improvement in event-free survival or overall survival. Limitations of use: the safety of Perjeta as part of a doxorubicin-containing regimen has not been established. The safety of Perjeta given for more than 6 cycles for early breast cancer has also not been established.
⚠️ Always consult a registered physician before taking any medicine.
Pharmacology
Pertuzumab is a recombinant humanized monoclonal antibody that targets the extracellular dimerization domain (Subdomain II) of the human epidermal growth factor receptor 2 protein (HER2). By binding this domain, Pertuzumab blocks ligand-dependent heterodimerization of HER2 with other HER family members, including EGFR, HER3, and HER4. As a result, Pertuzumab inhibits ligand-initiated intracellular signaling through two major signal pathways: mitogen-activated protein (MAP) kinase, and phosphoinositide 3-kinase (PI3K). Inhibition of these signaling pathways can result in cell growth arrest and apoptosis, respectively. In addition, Pertuzumab mediates antibody-dependent cell-mediated cytotoxicity.
Pregnancy & Breastfeeding
Pregnancy Category D. There are no adequate and well-controlled studies of Pertuzumab in pregnant women. If Pertuzumab is given during pregnancy, or if a patient becomes pregnant while receiving Pertuzumab or within 7 months after the last dose of Pertuzumab combined with Trastuzumab, she should be informed of the potential risk to the fetus.
Lactation: It is not known whether Pertuzumab passes into human breast milk, though human IgG does pass into breast milk. Since many drugs are secreted in breast milk and there is a potential for serious adverse effects in nursing infants from Pertuzumab, a decision should be made on whether to stop nursing or stop the drug, taking into account the elimination half life of Pertuzumab and how important the drug is to the mother.
⚠️ Talk to your doctor before taking any medicine during pregnancy or while breastfeeding.
Dosage Reference
⚠️ Reference ranges from official sources only. Consult your doctor for personalized dosing.