Last reviewed 2026-04-22 · How we verify

pertuzumab (P)

Pertuzumab is a monoclonal antibody that blocks HER2 dimerization, preventing HER2 from pairing with other HER receptors and inhibiting tumor cell growth signaling.

Pertuzumab is a monoclonal antibody that blocks HER2 dimerization, preventing HER2 from pairing with other HER receptors and inhibiting tumor cell growth signaling. Used for HER2-positive metastatic breast cancer (in combination with trastuzumab and chemotherapy), HER2-positive early-stage breast cancer (adjuvant and neoadjuvant settings).

At a glance

Mechanism of action

Pertuzumab binds to the extracellular dimerization interface of HER2, distinct from the trastuzumab binding site. By preventing HER2 from forming heterodimers with HER3 and other HER family members, it blocks downstream signaling pathways critical for HER2-driven cancer cell proliferation and survival. This complementary mechanism to trastuzumab allows for synergistic activity when used in combination.

Approved indications

• HER2-positive metastatic breast cancer (in combination with trastuzumab and chemotherapy)
• HER2-positive early-stage breast cancer (adjuvant and neoadjuvant settings)

Common side effects

• Diarrhea
• Nausea
• Fatigue
• Rash
• Vomiting
• Left ventricular dysfunction

Key clinical trials

• HER2 Directed Dendritic Cell Vaccine During Neoadjuvant Therapy of HER2+Breast Cancer (EARLY_PHASE1)
• A Clinical Study of Neoadjuvant Treatment With TQB2102 for Injection for Human Epidermal Growth Factor Receptor 2 (HER2) Positive Breast Cancer (PHASE3)
• Targeted Therapy Directed by Genetic Testing in Treating Patients With Advanced Refractory Solid Tumors, Lymphomas, or Multiple Myeloma (The MATCH Screening Trial) (PHASE2)
• Neoadjuvant Trastuzumab-rezetecan Plus Pertuzumab or Nab-Paclitaxel, Carboplatin, Trastuzumab, and Pyrotinib After Suboptimal Response to Neoadjuvant Dual HER2-Targeted Therapy Combined With Chemotherapy in HER2-Positive Early Breast Cancer (PHASE2)
• Study Comparing EC-T Verses PCb in the Adjuvant Chemotherapy of Non-triple Negative Breast Cancer (PHASE3)
• A Multicenter Phase III Clinical Study and Translational Research on Adaptive Neoadjuvant Therapy of De-escalation and Escalation for HER2-Positive Breast Cancer Based on Multi-Omics Response Evaluation Model (PHASE3)
• NeoAdjuvant Therapy With Trastuzumab-deruxtecan Versus Chemotherapy+Trastuzumab+Pertuzumab in HER2+ Early Breast Cancer (PHASE2)
• Pyrotinib Combined With Trastuzumab for Maintenance Therapy After First-line TH (P) Therapy for HER2+ABC

Primary sources

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