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Fostemsavir Pregnancy and Breastfeeding Warnings

Brand names: Rukobia

Medically reviewed by Last updated on Jul 18, 2023.

Fostemsavir Pregnancy Warnings

This drug should be used during pregnancy only if the benefit outweighs the risk to the fetus.
-According to some authorities: As a precaution, use should be avoided.

AU TGA pregnancy category: B3
US FDA pregnancy category: Not assigned.

Risk summary: Insufficient data available on use of this drug in pregnant women to inform a drug-related risk.

-A pregnancy exposure registry is available.

Animal studies have failed to reveal evidence of adverse developmental effects at clinically relevant temsavir exposures; animal studies have revealed evidence of embryolethality and teratogenicity at temsavir exposures associated with maternal toxicity. Oral administration of this drug to pregnant rats and rabbits during organogenesis showed no fetal abnormalities at temsavir exposures of about 180 (rats) and 30 (rabbits) times those in humans at the maximum recommended human dose (MRHD). In rats, at drug exposures about 200 times those in humans at the MRHD, fetal abnormalities (cleft palate, open eyes, shortened snout, microstomia, misaligned mouth/jaw, protruding tongue) and reduced fetal body weights were observed with maternal toxicity (reduced body weights and food intake); in rabbits, at drug exposures about 60 times those in humans at the MRHD, increased embryonic death associated with maternal toxicity was observed. In pregnant rats , temsavir and/or temsavir-derived metabolites crossed the placenta and were detectable in fetal tissue. There are no controlled data in human pregnancy; there are no/limited data (less than 300 pregnancy outcomes) from use of this drug in pregnant patients.

To monitor maternal-fetal outcomes of pregnant women exposed to antiretroviral therapy, an Antiretroviral Pregnancy Registry has been established. Healthcare providers are encouraged to prospectively register patients. For additional information:

AU TGA pregnancy category B3: Drugs which have been taken by only a limited number of pregnant women and women of childbearing age, without an increase in the frequency of malformation or other direct or indirect harmful effects on the human fetus having been observed. Studies in animals have shown evidence of an increased occurrence of fetal damage, the significance of which is considered uncertain in humans.

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

Fostemsavir Breastfeeding Warnings

Breastfeeding is not recommended during use of this drug.

Excreted into human milk: Unknown
Excreted into animal milk: Yes (temsavir and/or temsavir-derived metabolites)

-The effects in the nursing infant are unknown; potential for HIV-infected infants developing viral resistance and breastfed infants developing side effects similar to those in adults
-The US CDC, American Academy of Pediatrics, and manufacturer advise HIV-infected women not to breastfeed to avoid postnatal transmission of HIV to a child who may not yet be infected.
-Local guidelines should be consulted if replacement feeding is not an option.

See references

References for pregnancy information

  1. Cerner Multum, Inc. "UK Summary of Product Characteristics."
  2. Cerner Multum, Inc. "Australian Product Information."
  3. (2020) "Product Information. Rukobia (fostemsavir)." ViiV Healthcare

References for breastfeeding information

  1. Cerner Multum, Inc. "UK Summary of Product Characteristics."
  2. Cerner Multum, Inc. "Australian Product Information."
  3. (2013) "Infant feeding and transmission of human immunodeficiency virus in the United States." Pediatrics, 131, p. 391-6
  4. (2020) "Product Information. Rukobia (fostemsavir)." ViiV Healthcare
  5. Panel on Treatment of Pregnant Women with HIV Infection and Prevention of Perinatal Transmission (2021) Recommendations for the Use of Antiretroviral Drugs in Pregnant Women with HIV Infection and Interventions to Reduce Perinatal HIV Transmission in the United States.

Further information

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