Trastuzumab Emtansine Application Scope

HER2-positive metastatic breast cancer in patients previously treated with trastuzumab and a taxane
Early-stage HER2-positive breast cancer with residual invasive disease after neoadjuvant trastuzumab/taxane therapy (adjuvant use)

Trastuzumab Emtansine Characteristics

Ingredients:
- Active: Ado-trastuzumab emtansine — an antibody–drug conjugate combining trastuzumab (HER2-targeting monoclonal antibody) with cytotoxic agent DM1 via a thioether linker
Properties: Targets HER2‑expressing tumor cells; internalization releases DM1 to inhibit microtubule assembly while trastuzumab retains its HER2 signaling inhibition and ADCC action
Packaging Specification: Lyophilized powder in single-dose vials. 100 mg or 160 mg per vial
Storage: Store unopened vials at 2–8 °C; do not freeze. After reconstitution or dilution, store at 2–8 °C for up to 4 hours (vial) and up to 24 hours in infusion bag
Expiry Date: Typically 24 months from manufacture; exact month/year on carton/vial
Executive Standard:
- U.S. FDA-approved biologic: BLA 125427
- Approved in EU, China, and other regions; full prescribing info follows regulatory standards
Approval Number: FDA: BLA 125427; initial approval February 22, 2013 for metastatic use, expanded May 3, 2019 for adjuvant early-stage use
Date of Revision:
- Metastatic approval: Feb 22, 2013
- Adjuvant approval: May 3, 2019
Manufacturer: Genentech, a member of the Roche Group; produced with Lonza manufacturing

Dosage and Administration:
- Dose: 3.6 mg/kg IV infusion every 21 days
- Preparation: Reconstitute vial (20 mg/mL), dilute in 250 mL saline (no dextrose); infuse via 0.2/0.22 µm filter over recommended time
- Cycles: Up to 14 cycles for adjuvant therapy, or until disease progression/unacceptable toxicity in metastatic setting
Adverse Reactions:
- Common (≥25%): fatigue, nausea, increased transaminases, musculoskeletal pain, hemorrhage, thrombocytopenia, headache, peripheral neuropathy, arthralgia
- Serious: hepatotoxicity (including fatal), left ventricular dysfunction, interstitial lung disease/pneumonitis, severe thrombocytopenia, pulmonary toxicity
Contraindications: None specified in U.S. label — no known absolute contraindications other than hypersensitivity to components
Precautions:
- Hepatotoxicity: Monitor liver enzymes and bilirubin each cycle; discontinue if ALT >3×ULN with bilirubin >2×ULN
- Cardiac: Monitor LVEF prior to and during treatment; withhold or discontinue based on LVEF criteria (<45% or ≥10% drop)
- Pulmonary: Discontinue permanently if interstitial lung disease or severe pneumonitis occurs
- Neuropathy: Withhold for grade ≥3 and resume at next-lower dose upon recovery

Drug Interactions:
Minimal CYP interactions; metabolism via CYP3A4/3A5 but no major dosing changes recommended
Use caution with other hepatotoxic or cardiotoxic agents; monitor overlapping toxicity

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.