Avelumab (Bavencio) is a programmed death ligand-1 (PD-L1) blocking antibody, indicated for the treatment of various advanced cancers, including metastatic Merkel cell carcinoma, urothelial carcinoma, and advanced renal cell carcinoma. Proper administration and dosage adjustment are crucial for ensuring efficacy and safety.
How to Administer Avelumab (Bavencio)
Route and Timing of Administration
Avelumab is administered via intravenous infusion, with each infusion lasting 60 minutes.
The standard administration frequency is once every 2 weeks, with specific dosages as follows: For Merkel cell carcinoma: 800 mg.
For urothelial carcinoma: 800 mg.
For renal cell carcinoma: 800 mg, in combination with oral axitinib 5 mg twice daily.
Treatment should continue until disease progression or the occurrence of unacceptable toxicity.
Pretreatment Before Medication
To reduce the risk of infusion-related reactions, it is recommended to administer pretreatment with antihistamines and acetaminophen before the first 4 infusions.
Whether to continue pretreatment thereafter should be determined based on the patient’s clinical condition and previous reaction.
Precautions for Preparation and Storage
Before use, check that the medicinal solution is clear, colorless to slightly yellow, and free of particles.
Inject the required dose into 250 mL of 0.9% or 0.45% sodium chloride injection, mix gently, and avoid shaking.
The prepared solution should be used within 4 hours at room temperature (≤25°C), or stored under refrigeration at 2°C–8°C for no more than 24 hours. It needs to be returned to room temperature before use.
Freezing or violent shaking is prohibited.
Dosage Adjustment of Avelumab (Bavencio)
Immune-Mediated Adverse Reactions
Pneumonia: Grade 2: Suspend medication; Grade 3 or 4: Discontinue medication permanently.
Colitis: Grade 2 or 3: Suspend medication; Grade 4: Discontinue medication permanently.
Hepatitis: For patients without liver metastasis: Suspend medication if AST/ALT > 3 times the upper limit of normal (ULN) or total bilirubin > 1.5 times ULN; discontinue medication permanently if AST/ALT > 8 times ULN or total bilirubin > 3 times ULN.
For patients with liver metastasis: Adjust according to specific criteria.
For endocrine disorders, nephritis, skin reactions, myocarditis, neurological toxicity, etc., corresponding measures should also be taken based on the severity.
Dosage Adjustment During Combined Medication
When used in combination with axitinib: If ALT/AST ≥ 3 times ULN but < 10 times ULN, and total bilirubin < 2 times ULN, both drugs should be suspended; re-administration may be considered after recovery.
If ALT/AST ≥ 10 times ULN, or ≥ 3 times ULN accompanied by total bilirubin ≥ 2 times ULN, both drugs should be discontinued permanently.
Administration of Avelumab (Bavencio) in Special Populations
Pregnant Women
Based on its mechanism of action, avelumab may cause harm to the fetus.
Animal studies have shown that inhibition of the PD-1/PD-L1 pathway may increase the risk of immune-mediated fetal rejection.
Women of childbearing age are advised to use effective contraceptive measures during treatment and for at least 1 month after the last dose.
Lactating Women
Currently, there is no data on whether avelumab is excreted in human milk.
In view of potential risks, it is recommended to discontinue breastfeeding during treatment and for at least 1 month after the last dose.
Pediatric Patients
Avelumab has been approved for the treatment of metastatic Merkel cell carcinoma in adolescents aged 12 years and older.
Its use in this age group is based on adult study data and pharmacokinetic extrapolation.
The efficacy in children under 12 years of age has not been established.

