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Class ⬇

Antiretroviral (Nucleoside Reverse Transcriptase Inhibitor)

PREGNANCY RECOMMENDATION:Human Data Suggest Low Risk (Maternal Benefit May Outweigh Any Potential Embryofetal Risk)

BREASTFEEDING RECOMMENDATION:*Contraindicated

Pregnancy Summary ⬆ ⬇

Data from the Antiretroviral Pregnancy Registry (APR) show that there have been more than 2,000 exposures to abacavir in human pregnancy. Of these, over 1,000 were in the first trimester with an overall congenital birth anomaly rate of about 2.7%, which falls within the expected range in the United States. Several other smaller studies have also not shown an increased rate. No pattern to the defects has been identified. The drug crosses the placenta, so some fetal exposure will occur. Animal studies did not show any embryofetal toxicity in two species at doses of less than 10 times the recommended human dose (RHD). In order to decrease the risk of perinatal transmission of HIV-1 to the neonate, this drug should not be withheld if a pregnant woman is infected with HIV-1 with a positive viral load, or is failing her current treatment regimen, and is a candidate for this drug’s usage. There is a pregnancy exposure registry that monitors pregnancy outcomes in patients using antiretroviral medicines during pregnancy. Health care providers are encouraged to call the APR at 1-800-258-4263.

Breastfeeding Summary ⬆ ⬇

Two studies have been located that described the use of abacavir during human lactation. A total of 26 women have been tested, and the drug has been found in breast milk, but at low levels. Median breast milk levels ranged from about 57 to 91 ng/mL. All of the calculated relative infant doses (RIDs) were less than 1%. *However, the current Centers for Disease Control and Prevention (CDC) recommendation is that mothers infected with HIV should not breastfeed their infants in order to reduce the risk of postnatal transmission of the virus to the neonate. In a clinical setting where a mother is not infected with HIV (or in cases where the HIV viral load is negative), the drug by itself is probably compatible. If the clinical decision is to use this drug while breastfeeding, the infant should be monitored for the most common reported adult side effects of nausea and headache (both leading to irritability), fatigue (lethargy), vomiting, poor sleep, and rash.

Reference ⬆

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