About trastuzumab deruxtecan
HER2-targeted antibody-drug conjugate
Used for
- Treats certain HER2-positive or HER2-low breast cancers
- Treats HER2-positive advanced gastric or gastroesophageal junction cancer
- Treats HER2-mutant advanced non-small cell lung cancer
- Treats other selected HER2-positive solid tumors
Usual adult dose
Usually 5.4 mg/kg intravenously every three weeks for breast or lung cancer; 6.4 mg/kg for gastric cancer. Specialist dosing varies by indication.
Common side effects
- Nausea, vomiting, constipation, or reduced appetite
- Low blood-cell counts and increased infection or bleeding risk
- Fatigue and hair loss
- Interstitial lung disease or pneumonitis
Important warnings
- Can cause serious, sometimes fatal, interstitial lung disease; new cough or breathing difficulty requires urgent assessment.
- Can cause severe neutropenia and infection.
- May harm an unborn baby; pregnancy testing and effective contraception are required around treatment.
- Infusion reactions and heart-function problems can occur; monitoring is needed.
Pregnancy
May cause fetal harm. Avoid during pregnancy; effective contraception is recommended during treatment and for seven months afterward for women, and four months for men with partners who could become pregnant.
Breastfeeding
Do not breastfeed during treatment and for seven months after the last dose.
Interactions
- Strong CYP3A inhibitors may increase exposure to the active drug; medication review is important.
- Other medicines that can cause lung inflammation may increase concern for lung toxicity.
AI-generated from general medical knowledge, not from this product's official leaflet. It may be incomplete or out of date. Not medical advice — ask a pharmacist or doctor before making any decision.