Kadcyla Administration Frequency
Kadcyla (ado-trastuzumab emtansine) is administered intravenously at a dose of 3.6 mg/kg every 3 weeks (21-day cycle) until disease progression or unmanageable toxicity. 1
Administration Protocol
The FDA-approved administration schedule for Kadcyla follows a specific protocol:
First infusion: Administer over 90 minutes
- Observe patients during infusion and for at least 90 minutes following the initial dose
- Monitor for fever, chills, or other infusion-related reactions
Subsequent infusions: Administer over 30 minutes if prior infusions were well tolerated
- Continue observation during infusion and for at least 30 minutes afterward
Duration of Treatment
Treatment duration depends on the indication:
- Metastatic Breast Cancer (MBC): Continue treatment until disease progression or unmanageable toxicity
- Early Breast Cancer (EBC): Complete a total of 14 cycles unless disease recurrence or unmanageable toxicity occurs 1
Dose Modifications
Dose modifications may be necessary based on adverse reactions:
- Do not re-escalate the dose after a reduction
- If a dose is delayed or missed, administer as soon as possible
- Maintain the 3-week interval between doses
- Dose reduction schedule:
- Starting dose: 3.6 mg/kg
- First reduction: 3.0 mg/kg
- Second reduction: 2.4 mg/kg
- Further reduction needed: Discontinue treatment 1
Important Considerations
- Patient Selection: Ensure proper patient selection based on HER2 protein overexpression or HER2 gene amplification in tumor specimens
- Monitoring: Regular cardiac monitoring is essential due to potential cardiotoxicity
- Toxicity Management: Dose modifications may be required for increased transaminases, hyperbilirubinemia, left ventricular dysfunction, thrombocytopenia, pulmonary toxicity, or peripheral neuropathy 1
Common Side Effects
The most common adverse reactions (>25%) with Kadcyla include:
- Fatigue
- Nausea
- Increased transaminases
- Musculoskeletal pain
- Hemorrhage
- Thrombocytopenia
- Headache
- Peripheral neuropathy
- Arthralgia 2
Kadcyla should not be substituted for or with trastuzumab, as they are different medications with different dosing schedules and safety profiles 1.