Nivolumab and Breastfeeding

Summary of use during lactation

Nivolumab milk levels in one mother were unexpectedly high and appeared to accumulate with repeated doses, possibly because it is an IgG4 antibody rather than the more typical IgG1 for other monoclonal antibodies It is also likely to be partially destroyed in the infant's gastrointestinal tract and absorption by the infant is probably minimal.[1] However, until more data become available, nivolumab should probably be avoided during breastfeeding, especially while nursing a newborn or preterm infant. The manufacturer recommends that breastfeeding be discontinued during nivolumab therapy and for 5 months after the last dose of the drug.

Drug levels in milk and infant serum

Maternal Levels. A mother with melanoma was started on intravenous nivolumab 480 mg every four weeks at 6 weeks post-partum. Seventy-two breast milk samples were collected over a 34-day period during the first and second cycles of therapy. A peak concentration of 157 mcg/L occurred on day 3 after the first dose, then after a decline in concentrations another increase in concentrations started at day 7 reaching a peak concentration of 503 mcg/L on day 13. The milk concentration at the time of the second dose on day 27 was about 175 mcg/L and the peak milk concentration of nivolumab at 7 days after the second dose was higher after the second dose. The authors speculated that nivolumab accumulation in milk could continue because of its long half-life.[2] 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.

References

1. Anderson PO. Monoclonal antibodies during breastfeeding. Breastfeed Med 2021;16:591-3.33956488 PubMed
2. de Jong K, Damoiseaux D, Pluim D, et al. High accumulation of nivolumab in human breast milk: A case report. Biomed Pharmacother 2023;166:115354.37625324 PubMed