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Patisiran Pregnancy and Breastfeeding Warnings

Patisiran is also known as: Onpattro

Medically reviewed by Last updated on Aug 22, 2018.

Patisiran Pregnancy Warnings

In one rabbit study, IV administration to pregnant rabbits every week during the period of organogenesis produced no effects on embryofetal development; in a second rabbit study with higher doses, administration to pregnant rabbits resulted in embryofetal mortality and reduced fetal body weight at the mid and high doses, which were also associated with maternal toxicity. IV administration to pregnant rats every week throughout pregnancy and lactation resulted in no adverse developmental effects to the offspring. 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.

Benefit should outweigh risk

US FDA pregnancy category: Not assigned

Risk Summary: There is no available data on use in pregnant women to inform a drug-associated risk; this drug is known to reduce serum vitamin A levels and vitamin A is essential for normal embryofetal development; in an animal study, developmental toxicity has been observed at maternally toxic doses.

-It is unknown what the expected maternal effects of reduced serum transthyretin (TTR) and vitamin A supplementation will have on the fetus.

See references

Patisiran Breastfeeding Warnings

Benefit should outweigh risk

Excreted into human milk: Unknown
Excreted into animal milk: No (lipid components: yes)

-There are no data on the effects of this drug on the breastfed infant or its effects on milk production.
-The developmental and health benefits of breastfeeding should be considered along with the mother's clinical need for this drug and any potential adverse effects to the breastfed infant from the drug or from the underlying maternal condition.

This drug was not detected in the milk of lactating rats; however, the lipid components were present.

See references

References for pregnancy information

  1. "Product Information. Onpattro (patisiran)." Alnylam Phamraceuticals, Cambridge, MA.

References for breastfeeding information

  1. "Product Information. Onpattro (patisiran)." Alnylam Phamraceuticals, Cambridge, MA.

Further information

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