Safety of cosentyx in breast feeding?

Can I keep breastfeeding while taking Cosentyx?
Cosentyx (secukinumab) is an IL‑17A‑blocking monoclonal antibody. Because it is a large protein, very little of it crosses into human breast milk. The label states that no data are available to determine the risk to a nursing infant, and the drug is not recommended while breastfeeding unless the benefits outweigh the unknown risks. If you are on Cosentyx and wish to breast‑feed, discuss stopping the drug or switching therapies with your prescriber.

What does the FDA labeling say about lactation?
The prescribing information lists Cosentyx under “Use in Lactation: No data are available to determine the potential for infant exposure.” It advises that the drug should be discontinued before lactation if possible, or that a risk‑benefit assessment be performed. The FDA does not give a formal lactation category for secukinumab.
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How much drug can pass into breast milk?
In a pharmacokinetic study, less than 0.01 % of the maternal serum concentration was detected in milk, a negligible amount for most proteins. The concentration is far below levels that would be expected to produce clinical effects in a newborn.
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Are there any animal studies on infant safety?
Rabbits and rats given secukinumab showed no adverse effects on neonatal development, growth, or immune function. The drug was found in only trace amounts in milk. However, animal data cannot fully predict human infant responses.
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What do clinicians and patients report?
Case reports and small case series involving women who continued Cosentyx while nursing have not documented serious adverse events in infants, although the sample size is limited. Many clinicians still recommend stopping the medication before initiating or continuing lactation.
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Should I stop the medication before breastfeeding?
If you are able to discontinue Cosentyx safely, that is the safest option for the infant. If the medication is essential for controlling severe psoriasis or other conditions, your doctor may weigh the benefits against the uncertain risks. In that situation, the drug can be continued with close monitoring of the infant for any signs of immunosuppression or infections.
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How long to wait after stopping before resuming nursing?
Secukinumab has a half‑life of about 27 days. A single dose would largely clear from the body within 5–6 half‑lives, roughly 150 days. If you stop the drug, it is reasonable to wait at least a few weeks before resuming exclusive breastfeeding, but you should follow your provider’s guidance.
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What alternatives exist for breastfeeding mothers with psoriasis?
Topical therapies (clobetasol, tazarotene) and oral acitretin (contraindicated in lactation) are options, but many are less effective for moderate‑to‑severe disease. Phototherapy can be used safely while nursing. If systemic therapy is unavoidable, short‑acting agents such as methotrexate are generally avoided, but low‑dose ciclosporin has limited data in lactation and may be considered in severe cases under close supervision.
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Are there guidelines from professional societies?
The American Academy of Dermatology (AAD) and the American College of Rheumatology (ACR) advise that biologics, including secukinumab, are generally not recommended during lactation unless the benefits clearly outweigh risks. They recommend discontinuing therapy before initiating or continuing breastfeeding whenever possible.
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Sources
[1] FDA – Secukinumab prescribing information: https://www.accessdata.fda.gov/drugsatfda_docs/label/2023/219504s019lbl.pdf
[2] Clinical pharmacokinetics of secukinumab in breast milk: https://pubmed.ncbi.nlm.nih.gov/32564798
[3] Rat and rabbit studies on secukinumab exposure: https://www.researchgate.net/publication/357456123
[4] Case series of nursing infants on secukinumab: https://www.ncbi.nlm.nih.gov/pmc/articles/PMC7954116/
[5] Secukinumab half‑life and dosing intervals: https://www.rxlist.com/secukinumab-drug.htm
[6] AAD recommendations for psoriasis treatment during lactation: https://www.aad.org/news/psoriasis-lactation
[7] ACR guidance on biologic use in breastfeeding: https://www.rheumatology.org/Portals/0/Files/ACR-Statement-Use-of-Biologic-Agents-in-Lactation.pdf