Inetetamab Application Scope

Approved in China (June 2020) for HER2-positive metastatic breast cancer, used in combination with chemotherapy (e.g., vinorelbine, HER2 TKIs, pertuzumab)

Inetetamab Characteristics

Ingredients:
- Active Ingredient: Inetetamab – a recombinant humanized anti-HER2 monoclonal antibody (trastuzumab-like Fab with Fc engineered at positions D359 and L361 for enhanced ADCC)
Properties:
- Pan-HER2-targeting mAb that binds HER2 extracellular domain IV
- Engineered Fc domain confers about 1.11× stronger ADCC than trastuzumab
Packaging Specification: Injection vials containing 50 mg or 100 mg inetetamab for IV infusion
Storage: Store in original vials at 2–8 °C (refrigerated); do not freeze
Expiry Date: Generally 24 months from manufacture; exact date printed on vial/carton
Executive Standard: Complies with China’s NMPA biologics standards; first domestically developed anti-HER2 monoclonal antibody
Approval Number: NMPA approval granted in June 2020 for MBC indication; investigational approval (2004 L02352) was secured under NMPA in July 2004
Date of Revision: Launched in June 2020; clinical updates ongoing through 2024 (e.g., neoadjuvant HOPES trial and real‐world studies)
Manufacturer: Developed and marketed by Sunshine Guojian Pharmaceutical (3SBio), a subsidiary of 3SBio in Shanghai

Guidelines for the Use of Inetetamab

Dosage and Administration:

IV Administration: Examples from trials:
- HOPES regimen – loading dose of 4 mg/kg, then 2 mg/kg weekly with vinorelbine; alternatively 8/6 mg/kg every 3 weeks
- Standard clinical regimen – 6 mg/kg IV every 3 weeks plus chemotherapy or dual HER2
Adverse Reactions:
- Hematologic: Grade 3–4 neutropenia/leukopenia (~15%)
- General: Diarrhea, nausea, vomiting, fatigue reported; in one real-world study, any-grade AEs occurred in 96%, with grade ≥3 in ~30% (most commonly diarrhea and myelosuppression)
- Safety profile: Manageable across regimens; no new safety signals noted
Contraindications: No specific contraindications reported; hypersensitivity to inetetamab or excipients presumed as general precaution.
Precautions:
- Infusion reactions & hypersensitivity: Monitor during and after administration
- Myelosuppression: Regular blood count monitoring and manage neutropenia/leukopenia as needed
- Diarrhea: Monitor and treat promptly—especially when combined with HER2 TKIs
- Cardiac/Pulmonary: Although rare, continued vigilance during anti-HER2 therapy is advised

Interactions

Drug Interactions:
Combination regimens: Used safely with chemotherapy (vinorelbine, taxanes, carboplatin), TKIs (pyrotinib), and pertuzumab; can be integrated into dual-targeting strategies
No significant metabolic drug interactions reported for IV biologics (non-CYP mediated)

Note:

If there is a new packaging for the drug, the new packaging shall prevail. The above information is sourced from DengYue Medicine.
It is only for internal discussion among medical staff and does not serve as a basis for medication. For specific medication guidelines, please consult the attending physician.