Summary of Use during Lactation

The US FDA withdrew emergency-use authorization of bamlanivimab and etesevimab in June of 2021 because of a lack of efficacy against COVID-19 variants. Bamlanivimab is a monoclonal antibody given together with etesevimab. Both are directed against the SARS-CoV-2 virus that causes COVID-19. No information is available on the clinical use of bamlanivimab during breastfeeding. Because bamlanivimab is a large protein molecule with a molecular weight of 146,000 Da the amount in milk is likely to be very low.[1] It is also likely to be partially destroyed in the infant's gastrointestinal tract and absorption by the infant is probably minimal.[2] Until more data become available, bamlanivimab should be used with caution during breastfeeding, especially while nursing a newborn or preterm infant.

Drug Levels

Maternal Levels. Relevant published information was not found as of the revision date.

Infant Levels. Relevant published information was not found as of the revision date.

Effects in Breastfed Infants

Relevant published information was not found as of the revision date.

Effects on Lactation and Breastmilk

Relevant published information was not found as of the revision date.

Alternate Drugs to Consider

Nirmatrelvir, Remdesevir

References

1.

Stratigakis A, Paty D, Zou P, et al. A regression approach for assessing large molecular drug concentration in breast milk. Reprod Breed 2023;3:199-207. doi:10.1016/j.repbre.2023.10.003 [CrossRef]

2.

Anderson PO. Monoclonal antibodies during breastfeeding. Breastfeed Med 2021;16:591-3. [PubMed: 33956488]

Substance Name

Bamlanivimab

CAS Registry Number

2423943-37-5

Drug Class

Breast Feeding

Lactation

Milk, Human

Antibodies, Monoclonal

Antibodies, Viral

Antiviral Agents