Abatacept Pregnancy Warnings
Use is not recommended unless clearly needed.
AU TGA pregnancy category: C
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; this drug may affect the immune system in the fetus.
Comments:
-A pregnancy exposure registry is available.
-Women of childbearing potential should use effective contraception during therapy and up to 14 weeks after the last dose.
-Administration of live vaccines to infants exposed to this drug in utero is not recommended for 14 weeks to 5 months after the mother's last exposure to this drug during pregnancy; local protocol should be consulted regarding vaccination timing.
Animal studies have failed to reveal evidence of teratogenicity or embryotoxicity. IV administration during organogenesis to mice, rats, and rabbits produced exposures in rats and rabbits that were about 29 times the maximum recommended human dose (MRHD) on an AUC basis (at maternal doses of 200 mg/kg/day in rats and rabbits); no embryotoxicity or fetal malformations were observed in any species. In a pre- and postnatal study in rats (10, 45, or 200 mg/kg every 3 days from gestation day 6 through lactation day 21), alterations in immune function in female offspring, consisting of a 9-fold increase in T-cell-dependent antibody response (relative to controls) and thyroiditis in a single female pup, occurred at about 11 times the MRHD based on AUC (at maternal dose of 200 mg/kg); no adverse effects were observed at about 3 times the MRHD (a maternal dose of 45 mg/kg). It has not been determined if these findings indicate a risk for development of autoimmune diseases in humans exposed in utero. There are no controlled data in human pregnancy.
To monitor the outcomes of pregnant women exposed to this drug, a pregnancy registry has been established. Health care professionals are encouraged to register patients and pregnant women are encouraged to register themselves by calling 1-877-311-8972.
This drug may cross the placenta into the fetus when a woman is treated with this drug during pregnancy; thus, these infants may be at increased risk of infection. The safety of administering live vaccines to infants exposed to this drug in utero is unknown; it is unknown if the immune response of an infant exposed in utero and then administered a live vaccine is affected. Risks and benefits should be considered before vaccinating these infants.
AU TGA pregnancy category C: Drugs which, owing to their pharmacological effects, have caused or may be suspected of causing, harmful effects on the human fetus or neonate without causing malformations. These effects may be reversible. Accompanying texts should be consulted for further details.
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
Abatacept Breastfeeding Warnings
This drug is a large fusion protein that interferes with T-cell activation; it has a molecular weight of 92 kilodaltons. Only small amounts would be expected to enter breast milk.
A woman with rheumatoid arthritis resumed this drug (125 mg subcutaneously once a week) 2 days after delivery; her infant was exclusively breastfed, reportedly up until 12 months of age. Maternal serum and breast milk samples were collected after the 9th and 10th doses. Peak drug levels in milk occurred at about 3 days after each dose at 256 mcg/L; prior to the next dose, the trough level was 170 mcg/L. According to author estimation, the infant dose was between 25 and 38 mcg/kg/day (1% to 1.5% of weight-adjusted maternal dose). The woman's infant had no adverse effects and developed normally during the period of exclusive breastfeeding. She received routine childhood vaccinations at 3 months of age as well as rotavirus and BCG vaccination at 6 months of age; no infections or adverse immune reactions were observed after the vaccinations.
If this drug is required by the mother, it is not a reason to discontinue breastfeeding; however, an alternate agent may be preferred, particularly while breastfeeding newborn or preterm infants.
-According to some authorities: Breastfeeding is not recommended during use of this drug and for up to 14 weeks after the last dose.
Excreted into human milk: Yes (very low amounts)
Comments:
-The effects in the nursing infant are unknown; there is a potential for serious side effects in the breastfed child.
-The long half-life of this drug should be considered when discontinuing therapy.
See references