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Deutivacaftor / tezacaftor / vanzacaftor Pregnancy and Breastfeeding Warnings

Brand names: Alyftrek

Medically reviewed by Drugs.com. Last updated on Feb 24, 2025.

Deutivacaftor / tezacaftor / vanzacaftor Pregnancy Warnings

Safety has not been established during pregnancy.

US FDA pregnancy category: Not assigned

Risk summary: No data are available on the use of this combination drug in pregnant women to inform a drug-related risk.

Animal studies have not been reported with this triple combination product. Separate animal reproductive and developmental studies were conducted with vanzacaftor, tezacaftor, and ivacaftor. Vanzacaftor showed maternal toxicity (i.e., mortality, abortion, decreased mean body weight or body weight gains) and increased post-implantation loss, decreased live fetuses, decreased fetal body weight, and increased kidney malformations at very high doses (71 times the exposure at maximum recommended human dose [MRHD]). Tezacaftor showed maternal and fetal toxicity at lower doses (approximately 1 time or higher than the MRHD). Decreased fetal body weights and early developmental delays in pinna detachment, eye opening, and righting reflex occurred at a maternally toxic dose (based on maternal weight loss) that produced exposures approximately 2 times the exposure at the MRHD. Deutivacaftor is a deuterated isotopologue of ivacaftor with a toxicity profile similar to ivacaftor. Ivacaftor showed maternal toxicity (i.e., death, decreased food consumption, decreased mean body weight and body weight gain, decreased clinical condition, abortions) at doses greater than or equal to 50 mg/kg/day (approximately 3 times the MRHD). Placental transfer of vanzacaftor, tezacaftor, and ivacaftor was observed in animals. There are no controlled data in human pregnancy.

US FDA pregnancy category Not Assigned: The US FDA has amended the pregnancy labeling rule for prescription drug products to require labeling that includes a summary of risk, a discussion of the data supporting that summary, and relevant information to help health care providers make prescribing decisions and counsel women about the use of drugs during pregnancy. Pregnancy categories A, B, C, D, and X are being phased out.

See references

Deutivacaftor / tezacaftor / vanzacaftor Breastfeeding Warnings

Safety has not been established.

Excreted into human milk: Unknown
Excreted into animal milk: Vanzacaftor and Tezacaftor (Yes); Deutivacaftor (Unknown)

Comments:
-The effects in the nursing infant are unknown.
-If used during breastfeeding, consider monitoring infant liver enzymes and bilirubin.
-Examine infant for cataracts.
-There are no data on the presence of this product in human milk or its effects on milk production.
-Deutivacaftor, a deuterated form of ivacaftor, has not been evaluated; however, ivacaftor is excreted into the milk of lactating female rats.
-When a drug is present in animal milk, it is likely that the drug will be present in human milk.
-Consider developmental and health benefits of breastfeeding along with the mother's clinical need for this drug and any potential adverse effects on the breastfed child from drug or underlying maternal condition.

See references

References for pregnancy information

  1. (2024) "Product Information. Alyftrek (deutivacaftor/tezacaftor/vanzacaftor)." Vertex Pharmaceuticals

References for breastfeeding information

  1. (2024) "Product Information. Alyftrek (deutivacaftor/tezacaftor/vanzacaftor)." Vertex Pharmaceuticals
  2. Bethesda (MD): National Institute of Child Health and Human Development (US) (2025) Drugs and Lactation Database (LactMed) https://www.ncbi.nlm.nih.gov/books/NBK611184/

Further information

Always consult your healthcare provider to ensure the information displayed on this page applies to your personal circumstances.