The Basics
What is Adefovir?
Used to treat hepatitis B.
Brand names for Adefovir
Hepsera
How Adefovir is classified
Antiviral Agents, Anti-Retroviral Agents
Adefovir During Pregnancy
Adefovir pregnancy category
Category CNote that the FDA has deprecated the use of pregnancy categories, so for some medications, this information isn’t available. We still think it’s useful to list historical info, however, given what a common proxy this has been in the past.
What we know about taking Adefovir while pregnant
There are no adequate and well-controlled studies of HEPSERA in pregnant women. Chronic hepatitis B is a serious condition that requires treatment. HEPSERA should be used during pregnancy only if the potential benefit to the mother justifies the potential risk to the fetus. Reproduction studies with oral administration of adefovir dipivoxil to pregnant rats and rabbits showed no evidence of embryotoxicity or teratogenicity at systemic exposures equivalent to 23 times (rats) and 40 times (rabbits) that achieved in humans at the therapeutic dose. However, embryotoxicity and an increased incidence of fetal malformations (anasarca, depressed eye bulge, umbilical hernia and kinked tail) occurred when adefovir was administered intravenously to pregnant rats at 38 times the human therapeutic exposure. These adverse reproductive effects did not occur following an intravenous dose where exposure was 12 times the human therapeutic exposure. Because animal reproduction studies are not always predictive of human response, HEPSERA should be used during pregnancy only if clearly needed and after careful consideration of the risks and benefits [See Nonclinical Toxicology].
Taking Adefovir While Breastfeeding
What are recommendations for lactation if you're taking Adefovir?
Adefovir has not been studied in nursing mothers being treated for hepatitis B infection. An alternate drug may be preferred, especially while nursing a newborn or preterm infant. No differences exist in infection rates between breastfed and formula-fed infants born to hepatitis B-infected women, as long as the infant receives hepatitis B immune globulin and hepatitis B vaccine at birth. Mothers with hepatitis B are encouraged to breastfeed their infants after their infants receive these preventative measures.[1][2]
Maternal / infant drug levels
Adefovir has not been studied in nursing mothers being treated for hepatitis B infection. An alternate drug may be preferred, especially while nursing a newborn or preterm infant. No differences exist in infection rates between breastfed and formula-fed infants born to hepatitis B-infected women, as long as the infant receives hepatitis B immune globulin and hepatitis B vaccine at birth. Mothers with hepatitis B are encouraged to breastfeed their infants after their infants receive these preventative measures.[1][2]
Possible effects of Adefovir on milk supply
Relevant published information was not found as of the revision date.
Possible alternatives to Adefovir
(Hepatitis B) Interferon Alfa, Lamivudine, Tenofovir.
List of References
Lactation sources: Drugs and Lactation Database (LactMed) [Internet]. Bethesda (MD): National Library of Medicine (US); 2006-. Available from: https://www.ncbi.nlm.nih.gov/books/NBK501922/1. Visvanathan K, Dusheiko G, Giles M et al. Managing HBV in pregnancy. Prevention, prophylaxis, treatment and follow-up: Position paper produced by Australian, UK and New Zealand key opinion leaders. Gut. 2016;65:340-50. PMID: 26475631
2. Dionne-Odom J, Tita AT, Silverman NS. #38: Hepatitis B in pregnancy screening, treatment, and prevention of vertical transmission. Am J Obstet Gynecol. 2016;214:6-14. PMID: 26454123
Disclaimer: This material is provided for educational purposes only and is not intended for medical advice, diagnosis, or treatment. Consult your healthcare provider with any questions.
