Summary of Use during Lactation

Filgotinib is not approved in the US by the Food and Drug Administration. No information is available on the clinical use of filgotinib during breastfeeding. The European manufacturer and an expert opinion recommend that breastfeeding be discontinued during filgotinib therapy.[1-3]

Drug Levels

Filgotinib is primarily metabolized to GS-829845, an active metabolite that has about 10% the activity of filgotinib.

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.

References

1.

Selinger C, Laube R, Limdi JK, et al. Appropriateness of small molecule agents for patients with IBD of childbearing age - a RAND/UCLA appropriateness panel. Therap Adv Gastroenterol 2024;17:17562848241299737. [PMC free article: PMC11558739] [PubMed: 39539488]

2.

Rüegg L, Pluma A, Hamroun S, et al. EULAR recommendations for use of antirheumatic drugs in reproduction, pregnancy, and lactation: 2024 update. Ann Rheum Dis 2025;84:910–26. [PubMed: 40287311]

3.

Mahadevan U, Seow CH, Barnes EL, et al. Global consensus statement on the management of pregnancy in inflammatory bowel disease. Clin Gastroenterol Hepatol 2025;23 (11S):S1–S60. [PubMed: 40874901]

Substance Name

Filgotinib

CAS Registry Number

1206161-97-8

Drug Class

Breast Feeding

Lactation

Milk, Human

Enzyme Inhibitors

Protein Kinase Inhibitors

Signal Transduction Inhibitors

Janus Kinase Inhibitors

JAK Inhibitors