Summary of Use during Lactation

The US FDA has withdrawn emergency-use authorization for tixagevimab and cilgavimab because of a lack of efficacy against some strains of SARS-CoV-2. These drugs are monoclonal antibodies directed against the SARS-CoV-2 virus that causes COVID-19 and used for prophylaxis in immune-compromised individuals. No information is available on their clinical use during breastfeeding. Because tixagevimab and cilgavimab are large protein molecules, the amount in milk is likely to be very low.[1] They are 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, tixagevimab and cilgavimab 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

Tixagevimab and Cilgavimab

CAS Registry Number

2420564-02-7; 2420563-99-9

Drug Class

Breast Feeding

Lactation

Milk, Human

Antibodies, Monoclonal

Antibodies, Viral

Antiviral Agents