Disitamab vedotin is a HER2‑targeted antibody‑drug conjugate (ADC). It acts by specifically binding to the HER2 protein on the surface of tumor cells and releasing cytotoxic agents to kill tumor cells. It is mainly used for the treatment of solid tumors including locally advanced or metastatic gastric cancer and urothelial carcinoma with HER2 overexpression or positive immunohistochemistry (IHC). It must be administered strictly under the supervision of a physician.
1. Indications
HER2‑positive advanced gastric cancer: For patients with locally advanced or metastatic disease who have received at least two prior lines of systemic chemotherapy.
HER2‑positive urothelial carcinoma: For patients with locally advanced or metastatic disease who have failed platinum‑containing chemotherapy or are not eligible for such therapy.
2. Dosage and Administration
Recommended dose
2.5 mg/kg by intravenous infusion once every 2 weeks, until disease progression or unacceptable toxicity develops.
Dose modifications
Dosing may be interrupted, reduced, or permanently discontinued based on the severity of adverse reactions, at the discretion of the treating physician.
3. Common Adverse Reactions
Hematologic disorders
Leukopenia, neutropenia (blood counts should be monitored).
Gastrointestinal disorders
Nausea, vomiting, decreased appetite; gastrointestinal bleeding or perforation may occur in severe cases.
Skin reactions
Alopecia, rash, hand‑foot syndrome.
Other
Fatigue, peripheral neuropathy, hepatic dysfunction.
4. Contraindications and Cautions
Contraindications:
Hypersensitivity to any ingredient of disitamab vedotin.
Pregnancy (may cause fetal harm).
Cautions:
Use with caution and careful clinical evaluation in patients with moderate to severe hepatic impairment, active infections, or underlying cardiovascular disease.
5. Special Precautions
Pretreatment testing
HER2 expression status must be confirmed by immunohistochemistry (IHC) before initiation of treatment.
Hypersensitivity reactions
Chills, fever, and other infusion‑related reactions may occur; close monitoring is required during infusion.
Contraception
Patients of reproductive potential must use effective contraception during treatment and for 6 months after the last dose.
6. Drug Interactions
Concomitant use with strong CYP3A4 inhibitors (e.g., ketoconazole) may increase toxicity and may require dose adjustment.
When combined with other myelosuppressive agents (e.g., chemotherapy), intensified hematologic monitoring is recommended.
7. Storage Conditions
Unopened product
Store refrigerated at 2–8°C, protected from light. Do not freeze.
Prepared infusion solution
Use within 24 hours of reconstitution.
