Generic
Pertuzumab + Trastuzumab
2 brands available in the market
At a glance
Pertuzumab + Trastuzumab (Phesgo) is a combination used for the neoadjuvant and adjuvant treatment of HER2-positive early breast cancer and for HER2-positive metastatic breast cancer. It is administered as a subcutaneous injection.
Description
Pertuzumab and trastuzumab are recombinant humanized immunoglobulin G1κ monoclonal antibodies that target HER2. Pertuzumab binds to subdomain II and trastuzumab to subdomain IV, disrupting HER2 signaling through complementary mechanisms without competing. This results in augmented anti-proliferative activity and potent antibody-dependent cell-mediated cytotoxicity (ADCC) preferentially on HER2-overexpressing cancer cells.
Indications
- HER2-positive early breast cancer (neoadjuvant treatment)
- HER2-positive early breast cancer at high risk of recurrence (adjuvant treatment)
- HER2-positive metastatic or locally recurrent unresectable breast cancer
Therapeutic class
Targeted Cancer Therapy
Pharmacological class
HER2/neu Receptor Antagonist (Monoclonal Antibody Combination)
Pharmacology
Pertuzumab and trastuzumab bind to distinct HER2 epitopes (subdomains II and IV) and disrupt HER2 signaling through complementary mechanisms without competing. The combination provides augmented anti-proliferative activity in vitro and in vivo. Both IgG1 frameworks provide potent ADCC, preferentially on HER2-overexpressing cancer cells.
Mechanism of action
Binds to distinct HER2 epitopes to disrupt HER2 signaling through complementary mechanisms and activates antibody-dependent cytotoxicity.
Dosage
Adult Dose (Subcutaneous):
- Loading dose: 1200 mg pertuzumab / 600 mg trastuzumab
- Maintenance dose (every 3 weeks): 600 mg pertuzumab / 600 mg trastuzumab
- Neoadjuvant: 3-6 cycles with chemotherapy
- Adjuvant: Total of 1 year (maximum 18 cycles)
- Metastatic: With docetaxel until disease progression or unacceptable toxicity
Pediatric Dose: Safety and efficacy not established.
Administration
- For subcutaneous (SC) use only; do not administer intravenously
- Administer only in the thigh
- Administered by healthcare professional
- Patients currently receiving IV pertuzumab and trastuzumab can switch to Phesgo
Missed dose
If you miss a dose, consult your doctor.
Side effects
Common Side Effects (>30%):
- Fatigue
- Alopecia
- Diarrhea
- Nausea
- Vomiting
- Neutropenia
- Thrombocytopenia
- Anemia
Precautions & warnings
- Left Ventricular Dysfunction: May cause CHF and decreased LVEF; monitor cardiac function
- Embryo-fetal Toxicity: May cause fetal harm; avoid during pregnancy
- Check vial labels to prevent medication errors (do not confuse with IV pertuzumab/trastuzumab products)
- Avoid use during pregnancy and lactation
Contraindications
- Known hypersensitivity to pertuzumab, trastuzumab, or any of the excipients
Drug interactions
- Anthracyclines: Avoid for up to 7 months after stopping Pertuzumab (cardiac dysfunction risk)
Food interactions
Not food-related (SC injection).
Use in pregnancy
Use in Pregnancy: Avoid during pregnancy unless potential benefit for the mother outweighs potential risk to the fetus.
Pregnancy Category: D — always consult a doctor before taking during pregnancy.
Use in lactation
Use in Lactation: Human IgG is excreted in human milk; unknown if pertuzumab and trastuzumab are excreted; discontinue nursing during therapy and for 7 months after the last dose.
Pediatric use
Safety and efficacy not established in children and adolescents (<18 years).
Geriatric use
No dose adjustment required in patients ≥65 years of age.
Renal / hepatic impairment
Renal Impairment: No dose adjustment needed in mild or moderate renal impairment; no dose recommendation for severe renal impairment.
Hepatic Impairment: Safety and efficacy not studied; no dose recommendation can be made.
Overdose effects
No overdose information available; consult your doctor if overused.
Storage conditions
Store at 2-8°C in the refrigerator; keep in outer carton to protect from light; do not freeze.
Chemical structure
Pertuzumab + Trastuzumab (Phesgo)