Avonza Use In Pregnancy & Lactation

Women of childbearing potential: Based on the animal data, it is recommended that pregnancy should be avoided in women treated with efavirenz, one of the components of Tenofovir Disoproxil Fumarate/Lamivudine/Efavirenz 300 mg/300 mg/400 mg Tablets. Barrier contraception should always be used in combination with other methods of contraception (for example, oral or other hormonal contraceptives). Because of the long half-life of efavirenz, use of adequate contraceptive measures for 12 weeks after discontinuation of efavirenz is recommended. Women of childbearing potential should undergo pregnancy testing before initiation of Tenofovir Disoproxil Fumarate/Lamivudine/Efavirenz 300 mg/300 mg/400 mg Tablets.
Pregnancy: Studies of efavirenz in animals have shown reproductive toxicity, including marked teratogenic effects (see Pharmacology: Toxicology: Preclinical safety data under Actions). Cases of neural tube defects in infants born to women with first trimester exposure have been reported. The postmarketing data available (www.apregistry.com) including sufficient pregnancies to exclude a two-fold increase from baseline, does not demonstrate an increased number of malformations in mothers exposed to efavirenz, nor any specific pattern of malformations. Efavirenz should not be used during the first trimester of pregnancy.
Animal studies do not indicate direct or indirect harmful effects of tenofovir disoproxil fumarate with respect to pregnancy, foetal development, parturition or postnatal development (see Pharmacology: Toxicology: Preclinical safety data under Actions). In humans, the safety of tenofovir in pregnancy has not been fully established. Sufficient numbers of first trimester exposures have been monitored, however, to detect at least a twofold increase in the risk of overall birth defects. No increase in birth defects was seen (www.apregistry.com).
No increased risk of birth defects has been reported for lamivudine (www.apregistry.com). However, risks to the fetus cannot be ruled out.
Due to the possible teratogenic effects of efavirenz, Tenofovir Disoproxil Fumarate/Lamivudine/Efavirenz 300 mg/300 mg/400 mg Tablets should not be used during the first trimester of pregnancy, and only used during the subsequent trimester if the benefit is considered to outweigh the risk.
Breast feeding: In animal studies it has been shown that tenofovir is excreted into milk. It is not known whether tenofovir is excreted in human milk. Lamivudine is excreted into the breast milk of lactating mothers. It is not known whether efavirenz is excreted in human milk.
Current recommendations on HIV and breastfeeding (e.g. those from the WHO) should be consulted before advising patients on this matter. Preferred options may vary depending on the local circumstances.